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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MilestonesPaymentReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestones Payment Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MilestonesPaymentReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestones Payment Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MilestonesPaymentReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestones payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AnnualRentOperatingLeaseAggregateAfterIncrease_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Annual rent operating lease aggregate after increase.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AnnualRentOperatingLeaseAggregateAfterIncrease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Annual rent operating lease aggregate after increase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AnnualRentOperatingLeaseAggregateAfterIncrease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Annual Rent Operating lease Aggregate After Increase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position Location, Balance [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Amount [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax credits:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EventAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Event.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EventAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Event [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EventAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Event [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental disclosure of non-cash operating, investing and financing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Excluding Current Maturities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Long-term debt, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Change in Contingent Consideration, Liability, Increase (Decrease)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of CVR at fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NatureOfBusinessLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nature of business.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NatureOfBusinessLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature Of Business [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating expenses:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 2 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Significant Other Observable Inputs (Level 2) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total deferred tax assets, net of valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Net of Valuation Allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ComponentsOfInProcessResearchAndDevelopmentExpensesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Components of in process research and development expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ComponentsOfInProcessResearchAndDevelopmentExpensesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Components Of In Process Research And Development Expenses [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock par value per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SaleOfAssetGuaranteedUpfront_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Asset Guaranteed Upfront</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SaleOfAssetGuaranteedUpfront_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sale of asset guaranteed upfront.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SaleOfAssetGuaranteedUpfront_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of asset guaranteed upfront</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponReceiptOfWaiverOfMilestoneConditionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upon receipt of waiver of milestone conditions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponReceiptOfWaiverOfMilestoneConditionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upon Receipt Of Waiver Of Milestone Conditions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponReceiptOfWaiverOfMilestoneConditionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Upon Receipt Of Waiver Of Milestone Conditions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock shares outsstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAOneConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series A One Convertible Preferred Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAOneConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A One Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAOneConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series A-1 convertible preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAOneConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Series A-1 convertible preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash and Cash Equivalents, at Carrying Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding Reconciliation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Denominator:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tranche.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tranche [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Allowance [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Conversion of Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock for conversion of convertible notes, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementStrategyAndGovernanceAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management, Strategy, and Governance [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementPositionsOrCommitteesResponsibleReportToBoardFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskBoardOfDirectorsOversightTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Board of Directors Oversight [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShortTermDebtTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Debt [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilitiesOtherFiniteLivedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating right-of-use asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilitiesOtherFiniteLivedAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Operating right-of-use asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilitiesOtherFiniteLivedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Other Finite-Lived Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Redeemable Convertible Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from redeemable convertible preferred stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NonRule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-Rule 10b5-1 Arr Modified [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NonRule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non-Rule 10b5-1 Arrangement Modified [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NonRule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-Rule 10b5-1 Arrangement Modified</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeDuringPeriodFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Changes Measurement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeDuringPeriodFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedArrangementsToObtainGoodsAndServicesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Asset, Valuation Allowance [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOff_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Asset Acquired in Transaction Other than Business Combination or Joint Venture Formation, Writeoff</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentAssetAcquiredOtherThanThroughBusinessCombinationWrittenOff_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">In process research and development expense recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_HorizonCollaborationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Horizon collaboration agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_HorizonCollaborationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Horizon Collaboration Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_HorizonCollaborationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Horizon collaboration agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Temporary Equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PercentageOfOutstandingDebtToBeMaintainedWithTheLenderByWayOfCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Outstanding Debt To Be Maintained With The Lender By Way Of Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PercentageOfOutstandingDebtToBeMaintainedWithTheLenderByWayOfCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of outstanding debt to be maintained with the lender by way of cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Warrants to purchase common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesA1RedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upon the conversion of authorized series a1 redeemable convertible preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesA1RedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upon The Conversion Of Authorized Series A1 Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesA1RedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved upon the conversion of authorized Series A-1 preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities and stockholders' equity (deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payables and Accruals [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Current Maturities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted- Average Exercise Price, Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Lived Tangible Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeveranceCosts1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Severance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeveranceCosts1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment Related to Severance Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LeaseExpirationDateYearAndMonth_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease expiration date year and month.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LeaseExpirationDateYearAndMonth_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Expiration Date Year And Month</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LeaseExpirationDateYearAndMonth_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease expiration year and month</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total change in valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Valuation allowance period increase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskThirdPartyOversightAndIdentificationProcessesFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OtherSegmentItemsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other segment items [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OtherSegmentItemsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other segment items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Valuation Allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: Valuation allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. statutory tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Federal income tax expense at statutory rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementThirdPartyEngagedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Third Party Engaged [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentsIncorporatedByReferenceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Documents Incorporated by Reference [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentsIncorporatedByReferenceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Documents Incorporated by Reference</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Percent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective income tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Effective income tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares reserved for stock option exercises [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved upon the conversion of the convertible notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Jurisdiction [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Convertible Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of convertible debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from convertible debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CashConsiderationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash Consideration.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CashConsiderationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Consideration [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedContributionPlanAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution Plan [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_WarrantsIssuedToSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants issued to silicon valley bank.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_WarrantsIssuedToSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Issued To Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_WarrantsIssuedToSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants Issued To Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_USStatutoryTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US Statutory Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_USStatutoryTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">US Statutory Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_USStatutoryTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. statutory tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LossOnImpairmentOfEquityInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loss on impairment of equity investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LossOnImpairmentOfEquityInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss on impairment of equity investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LossOnImpairmentOfEquityInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss on impairment of equity investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedContributionPlanTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Contribution Plan [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DefinedContributionPlanTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined Contribution Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LegacyQ32Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Legacy Q32 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LegacyQ32Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legacy Q32 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LegacyQ32Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Legacy Q32</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Significant Accounting Policies [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Significant Accounting Policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property Plant and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCashAndCashEquivalentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Cash and Cash Equivalents [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCashAndCashEquivalentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ForeignExchangeContractsOptionContractsAndOtherForeignExchangeHedgingArrangementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Foreign exchange contracts option contracts and other foreign exchange hedging arrangements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ForeignExchangeContractsOptionContractsAndOtherForeignExchangeHedgingArrangementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Exchange Contracts Option Contracts And Other Foreign Exchange Hedging Arrangements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ForeignExchangeContractsOptionContractsAndOtherForeignExchangeHedgingArrangementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign exchange contracts &amp; other forign heding arrangements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeforeFirstOfJulyTwoThousandAndTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Before First Of July Two Thousand And Twenty Five [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeforeFirstOfJulyTwoThousandAndTwentyFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Before First Of July Two Thousand And Twenty Five [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Shares, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share based compensation by share based award options granted during the period shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementStrategyAndGovernanceTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management, Strategy, and Governance [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nontaxable or nondeductible items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CumulativeChangesOwnershipInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cumulative Changes Ownership Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CumulativeChangesOwnershipInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cumulative Changes Ownership Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CumulativeChangesOwnershipInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cumulative Changes Ownership Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CompanysEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Company's Effective Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CompanysEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Company's Effective Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CompanysEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Company's effective tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income (loss) per share-basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net income (loss) per share- basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncomeTaxDisclosureTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income tax disclosure.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncomeTaxDisclosureTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Number of Shares, Outstanding at Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Number of Shares, Outstanding at Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted- Average Exercise Price, Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FaceValueOfDebtInstrumentThatMayBeContingentlyBorrowed_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Face value of debt instrument that may be contingently borrowed.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FaceValueOfDebtInstrumentThatMayBeContingentlyBorrowed_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Face Value of Debt Instrument That May Be Contingently Borrowed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FaceValueOfDebtInstrumentThatMayBeContingentlyBorrowed_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Face value of debt instrument that may be contingently borrowed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt and Warrant Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SubleaseAggregateBaseRentObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sublease aggregate base rent obligation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SubleaseAggregateBaseRentObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sublease Aggregate Base Rent Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SubleaseAggregateBaseRentObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sublease aggregate base rent obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to reconcile net income (loss) to net cash used in operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPaidFederalAfterRefundReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPaidFederalAfterRefundReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Paid, Federal, after Refund Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPaidFederalAfterRefundReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income Tax Paid, Federal, after Refund Received, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DomesticCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal tax jurisdiction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DomesticCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Domestic federal income taxes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DomesticCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Domestic Tax Jurisdiction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Percent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax credits:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ParentCompanyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Parent company [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ParentCompanyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Parent Company [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Agreement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Agreement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' equity (deficit):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCommitmentFeeAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Commitment Fee Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCommitmentFeeAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility commitment fee amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Retained Earnings (Accumulated Deficit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalDeferred_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total deferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalDeferred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Total deferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalDeferred_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Total deferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Well-known Seasoned Issuer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Shares, Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConsultingAndAdvisoryAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Consulting and advisory agreements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConsultingAndAdvisoryAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Consulting And Advisory Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConsultingAndAdvisoryAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Consulting and Advisory Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Offering price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total intrinsic value of options exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentForeignTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Foreign</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentForeignTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Foreign Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tranche.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tranche [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event Considerations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Organization, Consolidation and Presentation of Financial Statements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_WalthamMassauchetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Waltham massauchets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_WalthamMassauchetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Waltham Massauchets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_WalthamMassauchetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Waltham Massauchets [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MaterialRightForThePurchaseOfADXNineHundredAndFourteenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Material right for the purchase of ADX nine hundred and fourteen.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MaterialRightForThePurchaseOfADXNineHundredAndFourteenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Material Right For The Purchase Of ADX Nine Hundred And Fourteen [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MaterialRightForThePurchaseOfADXNineHundredAndFourteenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Material right for the purchase of ADX-914</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount retained</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentPaymentTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Payment Terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentPaymentTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument terms of payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Federal statutory income tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PersonnelRelatedCostsExcludingStockBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Personnel Related Costs Excluding Stock Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PersonnelRelatedCostsExcludingStockBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Personnel Related Costs Excluding Stock Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PersonnelRelatedCostsExcludingStockBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Personnel-related costs (excluding stock-based compensation)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class of warrants or rights number of securities covered by warrants or rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UpfrontPaymentMade_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upfront payment made.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UpfrontPaymentMade_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upfront Payment Made</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UpfrontPaymentMade_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Upfront payment made</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities, convertible preferred stock and stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ComponentsOfInProcessResearchAndDevelopmentExpensesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">components of in process research and development expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ComponentsOfInProcessResearchAndDevelopmentExpensesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Components Of In Process Research And Development Expenses [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommitmentAndContingenciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitment and contingencies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommitmentAndContingenciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitment And Contingencies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ChangeInFairValueOfEquityInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Change In Fair Value Of Equity Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ChangeInFairValueOfEquityInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change In Fair Value Of Equity Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ChangeInFairValueOfEquityInvestment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Change in fair value of CVR liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MeasurementInputProbabilityOfEachScenarioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Measurement input probability of each scenario member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MeasurementInputProbabilityOfEachScenarioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Probability Of Each Scenario [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MeasurementInputProbabilityOfEachScenarioMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Probability of each scenario [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskRoleOfManagementTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Role of Management [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxCreditCarryforwardAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Credit Carryforward, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxCreditCarryforwardAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development tax credit carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_GainOnConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Gain On Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_GainOnConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain On Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_GainOnConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain on conversion of convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_GainOnConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain on convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted- Average Exercise Price, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less accumulated depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherOperatingIncomeExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Operating Income (Expense), Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherOperatingIncomeExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income (expense), net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheTwoMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tranche two milestone.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheTwoMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tranche Two Milestone [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheTwoMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tranche Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Effective Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument effective rate of interest percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PortionAtFairValueFairValueDisclosureMember_lbl" xlink:role="http://fasb.org/us-gaap/role/label/axisDefault">Portion at Fair Value Measurement [Member] [Default]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PortionAtFairValueFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Portion at Fair Value Measurement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Assumptions Used to Value Stock Options Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PatentsCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Patents costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PatentsCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Patents Costs [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PatentsCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Patent Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of Purchase Price of Convertible notes to Common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Carrying Amount, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total convertible preferred stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskMateriallyAffectedOrReasonablyLikelyToMateriallyAffectRegistrantFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Currency Transactions and Translations Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign Currency Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BempikibartMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Bempikibart [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BempikibartMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Bempikibart [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BempikibartMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bempikibart [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position Location, Balance [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use asset, operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskBoardCommitteeOrSubcommitteeResponsibleForOversightTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockOfferingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share Based Compensation Arrangement By Share Based Payment Award Stock Offering Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockOfferingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Arrangement By Share Based Payment Award Stock Offering Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockOfferingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock offering period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourStockPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reserved For Future Issuance Under Two Thousand And Twenty Four Stock Plan Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourStockPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reserved For Future Issuance Under Two Thousand And Twenty Four Stock Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourStockPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for future issuance under the 2024 Stock Incentive Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Taxes Paid, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash paid during the period for income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskProcessForInformingBoardCommitteeOrSubcommitteeResponsibleForOversightTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrimeRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prime Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrimeRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prime Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AnnualNetSalesThresholdTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Annual Net Sales Threshold Trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AnnualNetSalesThresholdTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Annual Net Sales Threshold Trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AnnualNetSalesThresholdTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Annual net sales threshold trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sales of Business, Affiliate and Productive Assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DepositTransferredToPayoutInvestigatorSiteFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deposit transferred to a payment processor to pay out investigator site fees</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DepositTransferredToPayoutInvestigatorSiteFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deposit Transferred to Payout Investigator Site Fees</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommitmentAndContingenciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitment and contingencies.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options to purchase common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Option, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncentiveFromLessor_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incentive from Lessor</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncentiveFromLessor_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee tenant improvement allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure in tabular form of common stock shares reserved for future issuance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure in Tabular form of Common Stock Shares Reserved for Future Issuance [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecurityDeposit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Deposit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecurityDeposit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Security deposit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other comprehensive gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentOnVentureDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal payments on venture debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentOnVentureDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment On Venture Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentOnVentureDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment On Venture Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesBConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series B Convertible Preferred Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesBConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series B Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesBConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series B convertible preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesBConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Series B convertible preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset, Periodic Reduction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-cash&#160;lease expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertibleDebtAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible debt agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertibleDebtAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertibleDebtAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Debt Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Remaining Contractual Term, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected stock price volatility range, maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition, Contingent Consideration, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent payment liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Asset Acquisition, Contingent Consideration, Liability, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">CVR liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term investments, Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Amortized Cost, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignTaxJurisdictionOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Tax Jurisdiction, Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignTaxJurisdictionOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other foreign jurisdictions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term investments, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAOneRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series a one redeemable convertible preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAOneRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A One Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAOneRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Series A One Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFinStmtErrorCorrectionFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Financial Statement Error Correction [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock from option exercises, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Shares, Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReceivedAdvancePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Received advance payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReceivedAdvancePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Received Advance Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReceivedAdvancePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Received Advance Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FacilitiesITAndInsuranceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Facilities, IT and insurance [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FacilitiesITAndInsuranceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Facilities, IT and insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Estimate of Fair Value Measurement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AchievementOfSpecifiedMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Achievement of specified milestones.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AchievementOfSpecifiedMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Achievement Of Specified Milestones [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AchievementOfSpecifiedMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Achievement Of Specified Milestones [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfEstimatedUsefulLifeOfAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of estimated useful life of assets.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash and Cash Equivalent, Noncurrent</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleNotesPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleNotesPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal balance of convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PayrollTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payroll tax credit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PayrollTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payroll Tax Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PayrollTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payroll tax credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MergersAndAquisitionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Mergers and Aquisitions Abstract</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_EquityMethodInvesteeNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Name [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Preferred Stock, Shares Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Preferred Stock, Shares Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Comprehensive income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term investments, Unrealized Gains</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and Development Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Capital Shares Reserved for Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock capital shares reserved for future issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share based awards, common stock reserved for issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Dilutive securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndSeventeenStockPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reserved for future issuance under two thousand and seventeen stock plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndSeventeenStockPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reserved For Future Issuance Under Two Thousand And Seventeen Stock Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndSeventeenStockPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for future issuance under the 2017 Stock Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Transaction Cost, Excluding Separately Recognized Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesConverted1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of Stock, Shares Converted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesConverted1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of Stock, Shares Converted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale of Equity Method Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sale of equity method investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Issued During Period Value to Homology Shareholders Reverse Recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Value to Homology Shareholders Reverse Recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock to Homology shareholders in reverse recapitalization, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State and local income taxes, net of federal income tax effect</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Stock-Based Compensation Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock from option exercises</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Comprehensive Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Components of Net Deffered Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Deferred Tax Assets and Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInNotesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Notes Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInNotesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain on conversion of the Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInNotesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Notes Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Agreements with Horizon</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive income (loss):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-Term Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FacilitiesITAndInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Facilities IT And Insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FacilitiesITAndInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Facilities IT And Insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FacilitiesITAndInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Facilities, IT and insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upon the conversion of authorized series b redeemable convertible preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upon The Conversion Of Authorized Series B Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved upon the conversion of authorized Series B preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStocksFromRsuVesting_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stocks from RSU Vesting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStocksFromRsuVesting_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stocks from RSU Vesting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStocksFromRsuVesting_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance Of Common Stocks From Rsu Vesting, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Tax Credit Carryforwards, Research</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capitalized R&amp;D expenditures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncomeLossBeforeProvisionForIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss before provision for income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncomeLossBeforeProvisionForIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) Before Provision For Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncomeLossBeforeProvisionForIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income (loss) before provision for income taxes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncomeLossBeforeProvisionForIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total income (loss) before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unamortized debt discount and issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement Inputs and Valuation Techniques [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheOneMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tranche one milestone.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheOneMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tranche One Milestone [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheOneMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tranche One Milestone [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheOneMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Tranche One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputExpectedTermMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, Expected Term [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputExpectedTermMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected Term (years) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantExercisePriceDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrant, Exercise Price, Decrease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantExercisePriceDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant, Exercise Price, Decrease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate Intrinsic Value, Vested and expected to vest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPaidForeignAfterRefundReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Paid, Foreign, after Refund Received</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPaidForeignAfterRefundReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Debt</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Temporary equity dividend rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity Dividend Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary equity dividend rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RestrictedCashAndCashEquivalentsNonCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted cash and cash equivalents non current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RestrictedCashAndCashEquivalentsNonCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash And Cash Equivalents Non Current [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RestrictedCashAndCashEquivalentsNonCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Cash And Cash Equivalents Non Current [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StateAndLocalJurisdictionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Domestic state and local income taxes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StateAndLocalJurisdictionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">State and Local Jurisdiction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock During Period Pre-Closing Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock During Period Pre-Closing Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock in the pre-closing financing, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesARedeemablePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series a redeemable preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesARedeemablePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A Redeemable Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions and Methodology [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NatureOfBusinessTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nature of business.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NatureOfBusinessTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature Of Business [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, $0.0001 par value; 10,000,000 shares authorized, no shares issued and outstanding at December 31, 2025 and December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OperatingLeaseAssetsLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating lease assets lessee [Abstract].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OperatingLeaseAssetsLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease Assets Lessee [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OperatingLeaseAssetsLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Sale of Assets and Asset Impairment Charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain on sale of asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain on sale of asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Significant Other Unobservable Inputs (Level 3) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PercentageOfSublicenseFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">percentage of sublicense fees.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PercentageOfSublicenseFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Sublicense Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PercentageOfSublicenseFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of sublicense fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLongTermLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Long-Term Lines of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLongTermLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from long term line of credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLongTermLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from borrowings under loan and security agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Financial Assets And Liabilities Measured At Fair Value On A Recurring Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfAmountsReportedInTheBalanceSheetInRespectOfOperatingLeaseAssetsAndCorrespondingLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure in tabular form of amounts reported in the balance sheet in respect of operating lease assets and corresponding liabilities [Table Text Block].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfAmountsReportedInTheBalanceSheetInRespectOfOperatingLeaseAssetsAndCorrespondingLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure In Tabular Form Of Amounts Reported In The Balance Sheet In Respect Of Operating Lease Assets And Corresponding Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfAmountsReportedInTheBalanceSheetInRespectOfOperatingLeaseAssetsAndCorrespondingLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Amounts Reported In The Balance Sheet In Respect Of Operating Lease Assets And Corresponding Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommonStockAndPre-FundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock And Pre-Funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommonStockAndPre-FundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock And Pre-Funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommonStockAndPre-FundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Stock And Pre-Funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FutureMinimumLeasePaymentDueUnderThisSublease_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Future minimum lease payment due under this sublease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FutureMinimumLeasePaymentDueUnderThisSublease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Future minimum lease payment due under this sublease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FutureMinimumLeasePaymentDueUnderThisSublease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Future minimum lease payment due under this sublease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfVentureDebtTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure in tabular form of venture debt.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfVentureDebtTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure In Tabular Form Of Venture Debt [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Loss Carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net operating loss carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restricted Cash and Cash Equivalents, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Non-CashRevenueFromSettlementOfCustomerRefundLiability_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Non-cash revenue from settlement of customer refund liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Non-CashRevenueFromSettlementOfCustomerRefundLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-Cash Revenue From Settlement Of Customer Refund Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Non-CashRevenueFromSettlementOfCustomerRefundLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non-Cash Revenue From Settlement Of Customer Refund Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (Note 11)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Leases [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Development Milestone Payment Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Development Milestone Payment Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development Milestone Payment Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and Administrative [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series b redeemable convertible preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series B Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series B Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesBRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Series B Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorFirmId_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Firm ID</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Basis Spread on Variable Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument variable interest spread</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityReverseStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity, Reverse Stock Split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityReverseStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' equity, reverse stock split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioForecastMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Forecast [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PersonnelRelatedAndConsultingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Personnel Related and Consulting [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PersonnelRelatedAndConsultingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Personnel Related and Consulting [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PersonnelRelatedAndConsultingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Personnel Related and Consulting [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AmountOfRefundLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of refund liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AmountOfRefundLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amount Of Refund Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AmountOfRefundLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Refund liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsQuantitativeInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement Inputs and Valuation Techniques [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_BusinessContactMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Contact [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Including Noncontrolling Interest</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfLongLivedAssetsHeldForUse_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment, Long-Lived Asset, Held-for-Use</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentStateAndLocalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current State and Local Tax Expense (Benefit)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CvrLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">CVR Liability</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SalesBasedMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sales based milestone.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SalesBasedMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sales Based Milestone [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockToAmgenValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Issuance of common stock to Amgen at fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockToAmgenValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of common stock to Amgen Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockToAmgenValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of common stock to Amgen Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockToAmgenValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Issuance of common stock to Amgen</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Tax Jurisdiction [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeIncludingSubsequentAcquisitionPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding common stock of the combined company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashFDICInsuredAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, FDIC Insured Amount</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Reportable Segments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Before thirty first of march two thousand and twenty six.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Gross</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTaxLiabilitiesInstallmentSale_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Installment sale</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTaxLiabilitiesInstallmentSale_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Tax Liabilities Installment Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfPrepaidExpensesAndOtherCurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of prepaid expenses and other current assets table text block.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Period [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign tax differences</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ADXZeroNineSevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ADX Zero Nine Seven [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ADXZeroNineSevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">ADX Zero Nine Seven [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ADXZeroNineSevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ADX-097 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityDividendsAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Dividends, Adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityDividendsAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary equity, dividends, adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash, cash equivalents, restricted cash and restricted cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable and Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable and accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Payable and Accrued Liabilities, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts payable and accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementBasisAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Basis [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Exercise Price of Warrants or Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class of warrants or rights exercise price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of the transaction price allocated to each performance obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AAPhaseTwoResearchServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">AA phase two research services.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AAPhaseTwoResearchServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AA Phase Two Research Services [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AAPhaseTwoResearchServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">AA phase 2 research services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsAndJointVenturesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments and Joint Ventures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsAndJointVenturesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Method Investment [Abstarct]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock During Period Pre-Closing Financing, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock During Period Pre-Closing Financing, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock in the pre-closing financing, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_IcfrAuditorAttestationFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ICFR Auditor Attestation Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_InvestmentsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Investments Disclosure Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_InvestmentsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investments Disclosure Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_InvestmentsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PeriodOfObligationToPayRoyalties_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Period of obligation to pay royalties.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PeriodOfObligationToPayRoyalties_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Period Of Obligation To Pay Royalties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PeriodOfObligationToPayRoyalties_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Period of obligation to pay royalties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Shares, Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCommitmentFeePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Commitment Fee Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCommitmentFeePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility commitment fee percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Disposition of Property Plant Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Loss on disposal of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityFourthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan and security fourth amendment agreement with silicon valley bank.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityFourthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan And Security Fourth Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityFourthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loan And Security Fourth Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity Stock Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Temporary equity stock issuance costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary equity stock issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborationAgreementContingentPaymentPayableExcessOfCashReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration agreement contingent payment payable excess of cash received.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborationAgreementContingentPaymentPayableExcessOfCashReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration Agreement Contingent Payment Payable Excess Of Cash Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborationAgreementContingentPaymentPayableExcessOfCashReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration agreement, contingent payment payable excess of cash received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OperatingLeaseLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating lease liabilities lessee [Abstract].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OperatingLeaseLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease Liabilities Lessee [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OperatingLeaseLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesPurchaseOfAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Purchase of Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesPurchaseOfAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock issued during period shares purchase of assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Security, Excluded EPS Calculation [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LesseeOperatingLeaseNotYetCommencedIncreaseInPercentageOfBaseRent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee operating lease not yet commenced increase in percentage of base rent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LesseeOperatingLeaseNotYetCommencedIncreaseInPercentageOfBaseRent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Operating Lease Not Yet Commenced Increase In Percentage Of Base Rent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LesseeOperatingLeaseNotYetCommencedIncreaseInPercentageOfBaseRent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage increase in initial annual base rent per square foot.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LongTermDebtBalloonPaymentPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Long term debt balloon payment percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LongTermDebtBalloonPaymentPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long Term Debt Balloon Payment Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LongTermDebtBalloonPaymentPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long term debt balloon payment percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementClassOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementClassOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Class of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Total deferred tax liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShortTermInvestmentsAcquiredInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Short Term Investments Acquired In reverse recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShortTermInvestmentsAcquiredInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short Term Investments Acquired In reverse recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShortTermInvestmentsAcquiredInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short Term Investments Acquired In reverse recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BusinessCombinationSharesConversionIntoRightsToPurchaseCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination shares conversion into rights to purchase common stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BusinessCombinationSharesConversionIntoRightsToPurchaseCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Shares Conversion Into Rights To Purchase Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BusinessCombinationSharesConversionIntoRightsToPurchaseCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combination shares conversion into rights to purchase common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeventhAmendmentToTheLoanAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Seventh amendment to the loan agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeventhAmendmentToTheLoanAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Seventh Amendment To The Loan Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeventhAmendmentToTheLoanAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Seventh Amendment To The Loan Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Realized Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Realized gains and losses on available-for-sale securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Realized Gain (Loss), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementStrategyAndGovernanceLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management, Strategy, and Governance [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RestrictedCashNonCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted cash non current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RestrictedCashNonCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash Non Current [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RestrictedCashNonCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Cash Non Current [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Instruments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tabular disclosure of recapitalization of assets and liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Recapitalization of Assets and Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Recapitalization of Assets and Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesARedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upon the conversion of authorized series a redeemable convertible preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesARedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upon The Conversion Of Authorized Series A Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UponTheConversionOfAuthorizedSeriesARedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved upon the conversion of authorized Series A preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyThreeTermALoanAdvanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand and twenty three term a loan advance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyThreeTermALoanAdvanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand And Twenty Three Term A Loan Advance [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyThreeTermALoanAdvanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Two Thousand And Twenty Three Term A Loan Advance [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments in Equity Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign tax effect</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConversionOfTemporaryEquityIntoPermanentEquityShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conversion of temporary equity into permanent equity shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConversionOfTemporaryEquityIntoPermanentEquityShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion Of Temporary Equity Into Permanent Equity Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConversionOfTemporaryEquityIntoPermanentEquityShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of temporary equity into permanent equity shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Scenario two member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Scenario two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OptionRepricing1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">OptionRepricing 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OptionRepricing1_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">OptionRepricing 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OptionRepricing1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Option Repricing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for vesting of restricted stock units [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationCVRLiabilityRevaluationIncomeTaxesPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">CVR liability revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationCVRLiabilityRevaluationIncomeTaxesPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation CVR Liability Revaluation Income Taxes Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationCVRLiabilityRevaluationIncomeTaxesPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective Income Tax Rate Reconciliation CVR Liability Revaluation Income Taxes Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average common shares - diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted Average Number of Shares Outstanding, Diluted, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted-average common shares outstanding-diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in unrealized gain (loss) on available for sale securities, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePriceOfCommonStockThroughPayrollDeductionsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share Based Compensation Arrangement By Share Based Payment Award Purchase Price Of Common Stock Through Payroll Deductions Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePriceOfCommonStockThroughPayrollDeductionsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Arrangement By Share Based Payment Award Purchase Price Of Common Stock Through Payroll Deductions Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePriceOfCommonStockThroughPayrollDeductionsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase of common stock through payroll deductions expressed in percentage of fair market value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected stock price volatility range, minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Taxes Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued taxes payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Scenario one member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Scenario one [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SummaryOfValuationAllowanceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Valuation Allowance [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SummaryOfValuationAllowanceTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Changes in The Valuation Allowance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income (loss) before provision for income taxes and loss from equity method investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DebtInstrumentConversionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument conversion price percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DebtInstrumentConversionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Conversion Price Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DebtInstrumentConversionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument conversion price percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborativeArrangementMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement milestone payments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborativeArrangementMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Milestone Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborativeArrangementMilestonePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration agreement, Aggregate amount of sales milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioUnspecifiedDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasurySecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US Treasury Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasurySecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">US Treasury securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LicenseAgreementWithBristolMayersEquibCompanyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License agreement with bristol mayers equib company.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LicenseAgreementWithBristolMayersEquibCompanyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement With Bristol Mayers Equib Company [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LicenseAgreementWithBristolMayersEquibCompanyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">License Agreement With Bristol Mayers Equib Company [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ADPhaseTwoResearchServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">AD phase two research services.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ADPhaseTwoResearchServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AD phase two research services [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ADPhaseTwoResearchServicesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">AD phase 2 research services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncreaseInNumberOfSharesReservedForIssuancePercentOfCommonStockOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase In Number Of Shares Reserved For Issuance Percent Of Common Stock Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncreaseInNumberOfSharesReservedForIssuancePercentOfCommonStockOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase In Number Of Shares Reserved For Issuance Percent Of Common Stock Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncreaseInNumberOfSharesReservedForIssuancePercentOfCommonStockOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in number of shares reserved for issuance, percent of common stock outstanding</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NumberOfDirectorsEntitledToBeElected_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of directors entitled to be elected.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NumberOfDirectorsEntitledToBeElected_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Directors Entitled To Be Elected</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NumberOfDirectorsEntitledToBeElected_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of directors entitled to be elected</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument conversion price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityFifthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan and security fifth amendment agreement with silicon valley bank.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityFifthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan And Security Fifth Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityFifthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loan And Security Fifth Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTaxLiabilitiesOtherFixedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fixed assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTaxLiabilitiesOtherFixedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Other Fixed Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTaxLiabilitiesOtherFixedAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Tax Liabilities, Other Fixed Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted- Average Exercise Price, Vested and expected to vest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reserved For Future Issuance Under Two Thousand And Twenty Four Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reserved For Future Issuance Under Two Thousand And Twenty Four Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for future issuance under the 2024 Employee Stock Purchase Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Useful Life (Years)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PhaseDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Phase.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PhaseDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Phase [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recent Accounting Pronouncements</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Maturities of Operating Lease Liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Before thirty first of march two thousand and twenty four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Before Thirty First Of March Two Thousand And Twenty Four [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentyFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Before Thirty First Of March Two Thousand And Twenty Four [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Conversion of Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of convertible preferred stock to common stock in connection with the Merge, Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalCurrentExpenseBenifit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalCurrentExpenseBenifit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Total Current Expense Benifit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalCurrentExpenseBenifit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Total Current Expense Benifit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share based awards, vesting period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate range, Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Domestic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">United States</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FairValueOfInterestExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair value of interest expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FairValueOfInterestExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair value Of Interest Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FairValueOfInterestExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value Of Interest Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone receivable upon the earlier of achievement of the first milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Receivables, Net, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Receivables, Net, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan and security agreement with silicon valley bank.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan And Security Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loan And Security Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Purchase of common share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Shares, Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Shares, Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability, current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Lease liability, current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesIntegratedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes Integrated [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAggregateDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Additional Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsLiabilitiesNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Short-Term Investments, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Off-Balance-Sheet Credit Exposure, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Off Balance Sheet Risk</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total segment and consolidated research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Total segment and consolidated research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Components of Income Tax Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CurrentLiabilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Current liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CurrentLiabilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Liabilities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CurrentLiabilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Liabilities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CurrentFederalTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current, Federal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Option, Activity [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityThirdAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan and security third amendment agreement with silicon valley bank.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityThirdAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan And Security Third Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecurityThirdAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Loan And Security Third Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Excess tax benefits on share-based payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Percent</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Temporary Equity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputExpectedDividendRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input, Expected Dividend Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputExpectedDividendRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Required market rates of return [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComputerEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Computer Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComputerEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Computer equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesIntegratedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes Integrated [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Net income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net income (loss)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Aggregate Intrinsic Value, Outstanding Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Aggregate Intrinsic Value, Outstanding Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate Intrinsic Value, Outstanding Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long term debt balloon payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Cost</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ChangeInFairValueOfConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in Fair Value Of Convertible Notes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants and Rights Outstanding, Term</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected dividend rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EstimatedAggregateProceedsFromEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Estimated aggregate proceeds from equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EstimatedAggregateProceedsFromEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Estimated Aggregate Proceeds From Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EstimatedAggregateProceedsFromEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated aggregate proceeds from equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate range</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCostsAndDiscounts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Issuance Costs and Discounts</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion, Converted Instrument, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument converted into equity number of shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from investing activities:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of options vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Income (Loss) Before Provision For Income Taxes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and Development [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllOtherSegmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Operating Segment [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTaxLiabilitiesAccruedExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Tax Liabilities, Accrued Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTaxLiabilitiesAccruedExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sale of asset</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Expenses and Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research Tax Credit Carryforward [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalSegmentNetLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Total Segment Net Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalSegmentNetLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Total Segment Net Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TotalSegmentNetLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total segment net income (loss)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity Disclosure [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PhaseAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Phase.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PhaseAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Phase [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExaminationDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExaminationDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Examination, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, after Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Assets, Fair Value Disclosure, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentAndRegulatoryMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Development and Regulatory Milestones Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentAndRegulatoryMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Development and Regulatory Milestones Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentAndRegulatoryMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development and regulatory milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments and Joint Ventures Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment in Equity Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration arrangement revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Revenues, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilitiesNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Liabilities, Net [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxLiabilitiesNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Conversion of Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock for conversion of Convertible Notes, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesATwoRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series a two redeemable convertible preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesATwoRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A Two Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesATwoRedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Series A Two Redeemable Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Excess tax benefits on share-based payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted- Average Exercise Price, Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentAggregateCost_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Equity investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentAggregateCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment, Aggregate Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentAggregateCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalizationWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Assumed in reverse recapitalization, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalizationWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Assumed in reverse recapitalization, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalizationWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted- Average Exercise Price, Assumed in reverse recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RecivedLoanAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Received loan agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RecivedLoanAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Recived Loan Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RecivedLoanAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Recived Loan Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentInformationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Information [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other noncurrent liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LongTermDebtPercentageBearingAnnualyPrimeRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long term debt percentage bearing annual prime rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LongTermDebtPercentageBearingAnnualyPrimeRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long Term Debt Percentage Bearing Annualy Prime Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LongTermDebtPercentageBearingAnnualyPrimeRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Long Term Debt Percentage Bearing Annualy Prime Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Future minimum lease payments due under this sublease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ConsolidatedEntitiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Consolidated Entities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in operating assets and liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Property Plant and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Weighted- Average Exercise Price, Outstanding at Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Weighted- Average Exercise Price, Outstanding at Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring and Nonrecurring [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NetOperatingLossCarryForwardsExpirationYear_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net operating loss carryforwards expiration year.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NetOperatingLossCarryForwardsExpirationYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Operating Loss Carry forwards Expiration Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NetOperatingLossCarryForwardsExpirationYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net operating loss carryforwards, expiration year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized tax benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Non-CashExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-cash expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Non-CashExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non-cash expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScheduleOfIncomeTaxesPaidTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Income Taxes Paid [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScheduleOfIncomeTaxesPaidTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Income Taxes Paid [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScheduleOfIncomeTaxesPaidTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Income Taxes Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement Frequency</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Expenses And Other Liabilities Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Expenses And Other Liabilities Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate range, Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PercentageOfConsolidatedCashToBeMaintainedWithTheLender_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of consolidated cash to be maintained with the lender.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PercentageOfConsolidatedCashToBeMaintainedWithTheLender_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Consolidated Cash To Be Maintained With The Lender</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PercentageOfConsolidatedCashToBeMaintainedWithTheLender_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of consolidated cash to be maintained with the lender</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee-related Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued compensation and related expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from financing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction, Purchases from Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related party transaction expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected term (years) range</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Measurements, Recurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Equity Method Investments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total minimum lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total minimum lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationStockBasedCompensationExpensePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationStockBasedCompensationExpensePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EffectiveIncomeTaxRateReconciliationStockBasedCompensationExpensePercent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationStockBasedCompensationExpensePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">EffectiveIncomeTaxRateReconciliationStockBasedCompensationExpensePercent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Research, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development tax credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Research and development tax credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LinesOfCreditCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LinesOfCreditCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Venture debt, current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LinesOfCreditCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Line of credit facility outstanding current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other income (expense), net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PrepaidExternalResearchAndDevelopmentCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid external research and development current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PrepaidExternalResearchAndDevelopmentCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid External Research And Development Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PrepaidExternalResearchAndDevelopmentCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid external research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandTwentyFourEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Thousand Twenty Four Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandTwentyFourEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Four Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandTwentyFourEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2024 Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AddressTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Address Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentAnnualReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Annual Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseOtherNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense Other, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseOtherNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtPercentageBearingFixedInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Percentage Bearing Fixed Interest, Percentage Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtPercentageBearingFixedInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible debt interest rate percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting of restricted stock, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EventDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Event.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EventDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Event [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EventDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Event [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DiscoveryAndOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Discovery and Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DiscoveryAndOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Discovery and Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DiscoveryAndOtherMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Discovery and Other [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share based awards, maximum contractual term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockToAmgenShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock to Amgen Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockToAmgenShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock to Amgen Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockToAmgenShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock to Amgen, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Comprehensive Income [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentOtherThanTemporaryImpairment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment, Other-than-Temporary Impairment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentOtherThanTemporaryImpairment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment charge</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Scenario three member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario Three [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ScenarioThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Scenario three [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressesAddressTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Addresses, Address Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedProfessionalFeesAndOtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued professional fees and other accrued liabilities current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedProfessionalFeesAndOtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Professional Fees And Other Accrued Liabilities Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedProfessionalFeesAndOtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued professional services and other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted- Average Exercise Price, Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OtherGAExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other G&amp;A expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OtherGAExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other G&amp;A expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, $0.0001 par value; 400,000,000 shares authorized, 12,858,047 and 12,197,615 shares issued and outstanding at December 31, 2025 2024, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UnrestrictedAndUnencumberedCashPercentageToBeMaintained_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unrestricted and unencumbered cash percentage to be maintained.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UnrestrictedAndUnencumberedCashPercentageToBeMaintained_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrestricted And Unencumbered Cash Percentage To Be Maintained</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_UnrestrictedAndUnencumberedCashPercentageToBeMaintained_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrestricted and unencumbered cash percentage to be maintained</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Available to Common Stockholders, Diluted, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net income (loss) attributable to common stockholders, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Income (Loss) Available to Common Stockholders, Diluted, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income (loss)-diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityExpirationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Expiration Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityExpirationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility expiration date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentAndSalesMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Development and sales milestone payment payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentAndSalesMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Development And Sales Milestone Payment Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentAndSalesMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development and sales milestone payment payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAssetsHeldForSale_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Asset, Held-for-Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAssetsHeldForSale_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction as an asset sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncomeTaxDisclosureLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConsolidationPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Consolidation, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConsolidationPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principles of Consolidation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lab equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net operating loss carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Operating Loss Carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Tax Assets, Operating Loss Carryforwards, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesForAssessingIdentifyingAndManagingThreatsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxCreditCarryforwardAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Credit Carryforward [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of Long-Lived Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">State income taxes, net of federal benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IndirectResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Indirect research and development expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IndirectResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indirect Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IndirectResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Indirect Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationGainLossOnConvertibleNoteConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain/loss on convertible note conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationGainLossOnConvertibleNoteConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation Gain loss On Convertible Note Conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EffectiveIncomeTaxRateReconciliationGainLossOnConvertibleNoteConversion_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effective Income Tax Rate Reconciliation Gain loss On Convertible Note Conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CurrentLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Current liabilities lessee [Abstract].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CurrentLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Liabilities Lessee [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CurrentLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityPublicFloat_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Public Float</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaidNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Taxes Paid, Net [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected stock price volatility range</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromCollaborators_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Collaborators</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromCollaborators_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Received amount from Horizon</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Mergers, Acquisitions and Dispositions Disclosures [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounting for the Merger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCashCashEquivalentsAndShortTermInvestmentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, and Investment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCashCashEquivalentsAndShortTermInvestmentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Short Term Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfVentureDebtLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure in tabular form of venture debt.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfVentureDebtLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure in tabular form of venture debt [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CapitalizedIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capitalized Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CapitalizedIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Capitalized Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CapitalizedIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capitalized intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PeriodDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PeriodDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Period [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NonCurrentLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non current liabilities lessee [Abstract].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NonCurrentLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non Current Liabilities Lessee [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NonCurrentLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Noncurrent:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term investments, Unrealized Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Short-term investments, Unrealized Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale of Short-Term Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maturities of short-term investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityVoluntaryFilers_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Voluntary Filers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RoyaltyAsAPercentageOfNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty as a percentage of net sales.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RoyaltyAsAPercentageOfNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty As A Percentage Of Net Sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RoyaltyAsAPercentageOfNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty as a percentage of sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure in tabular form of common stock shares reserved for future issuance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure In Tabular Form Of Common Stock Shares Reserved For Future Issuance [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Shares of Common Stock for Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income (expense), net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Nonoperating Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other income (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred State</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred State and Local Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInEntiretyOfTemporaryEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure in entirety of temporary equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInEntiretyOfTemporaryEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure In Entirety Of Temporary Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInEntiretyOfTemporaryEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityFrequencyOfPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Frequency of Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityFrequencyOfPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility frequency of payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheThreeMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tranche three milestone.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheThreeMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tranche Three Milestone [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TrancheThreeMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tranche Three [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementPositionsOrCommitteesResponsibleFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Positions or Committees Responsible [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ConsolidatedEntitiesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Consolidated Entities [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Effective income tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Provision for income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement Frequency</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EighthAmendmentToTheLoanAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Eighth Amendment To The Loan Agreement Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EighthAmendmentToTheLoanAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Eighth Amendment to the Loan Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PropertyPlantAndEquipmentUsefulLife1_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Property plant and equipment useful life 1.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PropertyPlantAndEquipmentUsefulLife1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property Plant And Equipment Useful Life 1</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromCollaborativeArrangementExcludingRevenueFromContractWithCustomer_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration agreement revenue</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Remaining Contractual Term, Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ExcessOfAccruedRightToPurchaseStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Excess of accrued right to purchase stock</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Expense (Benefit)</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current and deferred income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, New Issues</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Shares Authorized</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Shares, Vested</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTaxAssetsOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Tax Assets, Operating Lease Liability</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborationAgreementTransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration agreement transaction price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborationAgreementTransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration Agreement Transaction Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborationAgreementTransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration agreement, transaction price</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandTwentyFourStockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Four Stock Option and Incentive Plan [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_HorizonTherapeuticsIrelandDacMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Horizon Therapeutics Ireland DAC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_HorizonTherapeuticsIrelandDacMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Horizon Therapeutics Ireland DAC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax credit carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Tax Credit Carryforwards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Tax Assets, Tax Credit Carryforwards, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase In Common Stock Capital Shares Reserved For Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase In Common Stock Capital Shares Reserved For Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in number of shares reserved for issuance (shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development tax credits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsResearch_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecuritySecondAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan and security second amendment agreement with silicon valley bank.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecuritySecondAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan And Security Second Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LoanAndSecuritySecondAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Loan And Security Second Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Variable lease costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EstimatedAggregateProceedsFromDebtAndEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Estimated aggregate proceeds from debt and equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EstimatedAggregateProceedsFromDebtAndEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Estimated Aggregate Proceeds From Debt And Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_EstimatedAggregateProceedsFromDebtAndEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated aggregate proceeds from debt and equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Remaining Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease weighted average remaining lease term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseExpirationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Expiration Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseExpirationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease expiration date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfPrepaidExpensesAndOtherNoncurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of Prepaid Expenses and Other Noncurrent Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfPrepaidExpensesAndOtherNoncurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Prepaid Expenses and Other Noncurrent Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfPrepaidExpensesAndOtherNoncurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Prepaid Expenses and Other Noncurrent Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtPercentageBearingVariableInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Percentage Bearing Variable Interest, Percentage Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtPercentageBearingVariableInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long term debt variable interest rate percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AmountDueUnderAssetPurchaseAgreements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amounts due under Asset Purchase Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AmountDueUnderAssetPurchaseAgreements_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amount Due Under Asset Purchase Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AmountDueUnderAssetPurchaseAgreements_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount Due Under Asset Purchase Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredForeignIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred Foreign</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredForeignIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Foreign Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income (loss) from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Deficit [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsFrequentFlierLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredTaxAssetsFrequentFlierLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Tax Assets, Frequent Flier Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardRestrictedStockUnitsVestedAndExpectedToVestTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Company's RSU Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardRestrictedStockUnitsVestedAndExpectedToVestTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Restricted Stock Units, Vested and Expected to Vest [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityDateOfFirstRequiredPayment1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Date of First Required Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityDateOfFirstRequiredPayment1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility date of first required payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Pre-FundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre-Funded Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Pre-FundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre-Funded Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Pre-FundedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre-Funded Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series A Convertible Preferred Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A Convertible Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series A convertible preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesAConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Series A convertible preferred stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Discount Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease weighted average discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease liability, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease liabilities, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Quoted Prices in Active Markets (Level 1) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by (used in) financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FacilitiesITAndOtherAllocatedCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Facilities, IT and other allocated costs [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_FacilitiesITAndOtherAllocatedCostsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Facilities, IT and other allocated costs [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermDebtLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Debt [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Operating Lease Cost and Variable Lease Costs and Sub Lease Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nontaxable or nondeductible items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorLocation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RegulatoryMilestonePaymentUponApproval_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Regulatory Milestone Payment Upon Approval</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RegulatoryMilestonePaymentUponApproval_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Regulatory Milestone Payment Upon Approval</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RegulatoryMilestonePaymentUponApproval_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone Payment Based on Approval</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share Reconciliation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareReconciliationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Numerator:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExaminationLikelihoodOfUnfavorableSettlement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Examination, Likelihood of Unfavorable Settlement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExaminationLikelihoodOfUnfavorableSettlement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of computation of diluted net loss per share attributable to common stockholders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Jurisdiction [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OxbSolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Oxb Solutions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OxbSolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Oxb Solutions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OxbSolutionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Oxb Solutions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosureItemAmountsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLeaseNotYetCommencedRenewalTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Lease Not yet Commenced, Renewal Term</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Local Phone Number</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfStockDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Class of Stock [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share based awards, shares available for future grant</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unrecognised compensation cost, recognition period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SelfInsuranceReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Self Insurance Reserve</link:label>
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          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="qttb_HomologyMember" xlink:to="qttb_HomologyMember_lbl"/>
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  <xsd:element id="qttb_PropertyPlantAndEquipmentUsefulLife1" name="PropertyPlantAndEquipmentUsefulLife1" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
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  <xsd:element id="qttb_Non-CashExpensesMember" name="Non-CashExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_EstimatedAggregateProceedsFromDebtAndEquity" name="EstimatedAggregateProceedsFromDebtAndEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_UponTheConversionOfAuthorizedSeriesARedeemableConvertiblePreferredStockMember" name="UponTheConversionOfAuthorizedSeriesARedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TemporaryEquityDividendRate" name="TemporaryEquityDividendRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_PaymentToHorizon" name="PaymentToHorizon" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourEmployeeStockPurchasePlanMember" name="ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_EventAxis" name="EventAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LoanAndSecurityFifthAmendmentAgreementWithSiliconValleyBankMember" name="LoanAndSecurityFifthAmendmentAgreementWithSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock" name="ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_NumberOfDirectorsEntitledToBeElected" name="NumberOfDirectorsEntitledToBeElected" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_WarrantsIssuedToSiliconValleyBankMember" name="WarrantsIssuedToSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LoanAndSecuritySecondAmendmentAgreementWithSiliconValleyBankMember" name="LoanAndSecuritySecondAmendmentAgreementWithSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_HorizonCollaborationAgreementMember" name="HorizonCollaborationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_OtherSegmentItemsMember" name="OtherSegmentItemsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_VentureDebtTwoThousandTwentyAndTwoThousandAndTwentyThreeTermALoanMember" name="VentureDebtTwoThousandTwentyAndTwoThousandAndTwentyThreeTermALoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AccruedExpensesAndOtherLiabilitiesCurrent" name="AccruedExpensesAndOtherLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_EffectiveIncomeTaxRateReconciliationCVRLiabilityRevaluationIncomeTaxesPercent" name="EffectiveIncomeTaxRateReconciliationCVRLiabilityRevaluationIncomeTaxesPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_PeriodOfObligationToPayRoyalties" name="PeriodOfObligationToPayRoyalties" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_SummaryOfPrepaidExpensesAndOtherNoncurrentAssetsTableTextBlock" name="SummaryOfPrepaidExpensesAndOtherNoncurrentAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts" name="IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_CommitmentAndContingenciesLineItems" name="CommitmentAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CashConsiderationMember" name="CashConsiderationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_SeventhAmendmentToTheLoanAgreementMember" name="SeventhAmendmentToTheLoanAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AmountDueUnderAssetPurchaseAgreements" name="AmountDueUnderAssetPurchaseAgreements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_HorizonTherapeuticsIrelandDacMember" name="HorizonTherapeuticsIrelandDacMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_IndirectResearchAndDevelopmentExpense" name="IndirectResearchAndDevelopmentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_DeferredTaxLiabilitiesOtherFixedAssets" name="DeferredTaxLiabilitiesOtherFixedAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ReservedForFutureIssuanceUnderTwoThousandAndSeventeenStockPlanMember" name="ReservedForFutureIssuanceUnderTwoThousandAndSeventeenStockPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AccountingPoliciesTable" name="AccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ForeignExchangeContractsOptionContractsAndOtherForeignExchangeHedgingArrangementsMember" name="ForeignExchangeContractsOptionContractsAndOtherForeignExchangeHedgingArrangementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_MaterialRightForThePurchaseOfADXNineHundredAndFourteenMember" name="MaterialRightForThePurchaseOfADXNineHundredAndFourteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DeferredTaxAssetsOperatingLeaseLiability" name="DeferredTaxAssetsOperatingLeaseLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_LeaseholdImprovements" name="LeaseholdImprovements" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_DevelopmentAndSalesMilestonePaymentPayable" name="DevelopmentAndSalesMilestonePaymentPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ProceedsFromReverseRecapitalization" name="ProceedsFromReverseRecapitalization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_DeferredTaxLiabilitiesInstallmentSale" name="DeferredTaxLiabilitiesInstallmentSale" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_IndirectResearchAndDevelopmentMember" name="IndirectResearchAndDevelopmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CollaborationAgreementTransactionPrice" name="CollaborationAgreementTransactionPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_LicenseAgreementWithBristolMayersEquibCompanyMember" name="LicenseAgreementWithBristolMayersEquibCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalizationWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalizationWeightedAverageExercisePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_AchievementOfSpecifiedMilestonesMember" name="AchievementOfSpecifiedMilestonesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LossOnImpairmentOfEquityInvestment" name="LossOnImpairmentOfEquityInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_DisclosureInTabularFormOfVentureDebtTableTextBlock" name="DisclosureInTabularFormOfVentureDebtTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_TwoThousandAndTwentyTermALoanAdvanceMember" name="TwoThousandAndTwentyTermALoanAdvanceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DisclosureInTabularFormOfVentureDebtTable" name="DisclosureInTabularFormOfVentureDebtTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TrancheOneMilestoneMember" name="TrancheOneMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PrepaidExternalResearchAndDevelopmentCurrent" name="PrepaidExternalResearchAndDevelopmentCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_PaymentOfReverseRecapitalizationTransactionCosts" name="PaymentOfReverseRecapitalizationTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_MeasurementInputProbabilityOfEachScenarioMember" name="MeasurementInputProbabilityOfEachScenarioMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AccruedProfessionalFeesAndOtherAccruedLiabilitiesCurrent" name="AccruedProfessionalFeesAndOtherAccruedLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_SeriesBConvertiblePreferredStockMember" name="SeriesBConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PersonnelRelatedAndConsultingMember" name="PersonnelRelatedAndConsultingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CurrentLiabilitiesMember" name="CurrentLiabilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ScenarioTwoMember" name="ScenarioTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ADPhaseTwoResearchServicesMember" name="ADPhaseTwoResearchServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CommercialMilestonePaymentPayable" name="CommercialMilestonePaymentPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_USStatutoryTaxRate" name="USStatutoryTaxRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentyFiveMember" name="BeforeThirtyFirstOfMarchTwoThousandAndTwentyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DisclousreOfPrepaidExpensesOtherCurrentAssetsAndOtherNoncurrentAssetsTextBlock" name="DisclousreOfPrepaidExpensesOtherCurrentAssetsAndOtherNoncurrentAssetsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_TaxCreditCarryforwardsExpirationYear" name="TaxCreditCarryforwardsExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_AmountOfRefundLiability" name="AmountOfRefundLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_CumulativeChangesOwnershipInterest" name="CumulativeChangesOwnershipInterest" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_Non-CashRevenueFromSettlementOfCustomerRefundLiability" name="Non-CashRevenueFromSettlementOfCustomerRefundLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockOfferingPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockOfferingPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_SeriesARedeemablePreferredStockMember" name="SeriesARedeemablePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_OperatingLeaseLiabilitiesLesseeAbstract" name="OperatingLeaseLiabilitiesLesseeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CollaborativeArrangementMilestonePayments" name="CollaborativeArrangementMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_TotalDeferred" name="TotalDeferred" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance" name="IncreaseInCommonStockCapitalSharesReservedForFutureIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_RoyaltyAsAPercentageOfNetSales" name="RoyaltyAsAPercentageOfNetSales" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_BeforeFirstOfJulyTwoThousandAndTwentyFiveMember" name="BeforeFirstOfJulyTwoThousandAndTwentyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_SubleaseAggregateBaseRentObligation" name="SubleaseAggregateBaseRentObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_UponTheConversionOfAuthorizedSeriesA1RedeemableConvertiblePreferredStockMember" name="UponTheConversionOfAuthorizedSeriesA1RedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CollaborationAgreementContingentPaymentPayableExcessOfCashReceived" name="CollaborationAgreementContingentPaymentPayableExcessOfCashReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ScenarioOneMember" name="ScenarioOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ADXZeroNineSevenMember" name="ADXZeroNineSevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_SeriesAOneConvertiblePreferredStockMember" name="SeriesAOneConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AccruedResearchAndDevelopmentExpensesCurrent" name="AccruedResearchAndDevelopmentExpensesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_LoanAndSecurityFourthAmendmentAgreementWithSiliconValleyBankMember" name="LoanAndSecurityFourthAmendmentAgreementWithSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DisclosureInTabularFormOfAmountsReportedInTheBalanceSheetInRespectOfOperatingLeaseAssetsAndCorrespondingLiabilitiesTableTextBlock" name="DisclosureInTabularFormOfAmountsReportedInTheBalanceSheetInRespectOfOperatingLeaseAssetsAndCorrespondingLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_IssuanceOfCvrAtFairValue" name="IssuanceOfCvrAtFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ComponentsOfInProcessResearchAndDevelopmentExpensesAxis" name="ComponentsOfInProcessResearchAndDevelopmentExpensesAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LoanAndSecurityThirdAmendmentAgreementWithSiliconValleyBankMember" name="LoanAndSecurityThirdAmendmentAgreementWithSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DebtInstrumentConversionPricePercentage" name="DebtInstrumentConversionPricePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_WalthamMassauchetsMember" name="WalthamMassauchetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DeferredTaxLiabilitiesAccruedExpense" name="DeferredTaxLiabilitiesAccruedExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTableTextBlock" name="DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_RevenueUsedToDetermineTransactionPrice" name="RevenueUsedToDetermineTransactionPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_UponReceiptOfWaiverOfMilestoneConditionsMember" name="UponReceiptOfWaiverOfMilestoneConditionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TrancheTwoMilestoneMember" name="TrancheTwoMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LesseeOperatingLeaseNotYetCommencedIncreaseInPercentageOfBaseRent" name="LesseeOperatingLeaseNotYetCommencedIncreaseInPercentageOfBaseRent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_SixthAmendmentAgreementWithSiliconValleyBankMember" name="SixthAmendmentAgreementWithSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TwoThousandTwentyFourStockOptionAndIncentivePlanMember" name="TwoThousandTwentyFourStockOptionAndIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_MilestonesPaymentReceivable" name="MilestonesPaymentReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_AgreementDomain" name="AgreementDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TotalCurrentExpenseBenifit" name="TotalCurrentExpenseBenifit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_NatureOfBusinessTable" name="NatureOfBusinessTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TrancheAxis" name="TrancheAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_NumberOfCommonStockUnderlyingShares" name="NumberOfCommonStockUnderlyingShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_TwoThousandTwentyFourEmployeeStockPurchasePlanMember" name="TwoThousandTwentyFourEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_FaceValueOfDebtInstrumentThatMayBeContingentlyBorrowed" name="FaceValueOfDebtInstrumentThatMayBeContingentlyBorrowed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_BempikibartMember" name="BempikibartMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DevelopmentMilestonePaymentPayable" name="DevelopmentMilestonePaymentPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_NatureOfBusinessLineItems" name="NatureOfBusinessLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TotalSegmentNetLoss" name="TotalSegmentNetLoss" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_InvestmentsDisclosureAbstract" name="InvestmentsDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_GainOnConvertibleNotes" name="GainOnConvertibleNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_CommitmentAndContingenciesTable" name="CommitmentAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PercentageOfOutstandingDebtToBeMaintainedWithTheLenderByWayOfCash" name="PercentageOfOutstandingDebtToBeMaintainedWithTheLenderByWayOfCash" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_ReceivedAdvancePayment" name="ReceivedAdvancePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourStockPlanMember" name="ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourStockPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ChangeInFairValueOfConvertibleNotes" name="ChangeInFairValueOfConvertibleNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_CurrentLiabilitiesLesseeAbstract" name="CurrentLiabilitiesLesseeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_IncomeLossBeforeProvisionForIncomeTaxes" name="IncomeLossBeforeProvisionForIncomeTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalization" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalization" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_TrancheThreeMilestoneMember" name="TrancheThreeMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LeaseExpirationDateYearAndMonth" name="LeaseExpirationDateYearAndMonth" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_TwoThousandAndTwentyAndTwoThousandAndTwentyThreeTermALoanMember" name="TwoThousandAndTwentyAndTwoThousandAndTwentyThreeTermALoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PeriodAxis" name="PeriodAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_RegulatoryMilestonePaymentUponApproval" name="RegulatoryMilestonePaymentUponApproval" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_EffectiveIncomeTaxRateReconciliationGainLossOnConvertibleNoteConversion" name="EffectiveIncomeTaxRateReconciliationGainLossOnConvertibleNoteConversion" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_TemporaryEquityMember" name="TemporaryEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PercentageOfConsolidatedCashToBeMaintainedWithTheLender" name="PercentageOfConsolidatedCashToBeMaintainedWithTheLender" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_AAPhaseTwoResearchServicesMember" name="AAPhaseTwoResearchServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_UnrestrictedAndUnencumberedCashPercentageToBeMaintained" name="UnrestrictedAndUnencumberedCashPercentageToBeMaintained" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_LongTermDebtBalloonPaymentPercentage" name="LongTermDebtBalloonPaymentPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts" name="IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_RecivedLoanAgreement" name="RecivedLoanAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePriceOfCommonStockThroughPayrollDeductionsPercentage" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePriceOfCommonStockThroughPayrollDeductionsPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_DiscoveryAndOtherMember" name="DiscoveryAndOtherMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TrancheDomain" name="TrancheDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_UpfrontPaymentMade" name="UpfrontPaymentMade" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_FacilitiesITAndInsurance" name="FacilitiesITAndInsurance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_SummaryOfEstimatedUsefulLifeOfAssetsTableTextBlock" name="SummaryOfEstimatedUsefulLifeOfAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_PersonnelRelatedCostsExcludingStockBasedCompensation" name="PersonnelRelatedCostsExcludingStockBasedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_TemporaryEquityConversionPricePerShare" name="TemporaryEquityConversionPricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_TwoThousandAndTwentyThreeTermALoanAdvanceMember" name="TwoThousandAndTwentyThreeTermALoanAdvanceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_EstimatedAggregateProceedsFromEquity" name="EstimatedAggregateProceedsFromEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_LineOfCreditFacilityAmountThatMayBeContingentlyBorrowed" name="LineOfCreditFacilityAmountThatMayBeContingentlyBorrowed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_SeriesAConvertiblePreferredStockMember" name="SeriesAConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_EighthAmendmentToTheLoanAgreementMember" name="EighthAmendmentToTheLoanAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LineOfCreditFacilityAggregateAmountIncludingBalloonRepaymentPayable" name="LineOfCreditFacilityAggregateAmountIncludingBalloonRepaymentPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_MergerAndAcquisitionTable" name="MergerAndAcquisitionTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ComponentsOfInProcessResearchAndDevelopmentExpensesDomain" name="ComponentsOfInProcessResearchAndDevelopmentExpensesDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceLineItems" name="DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_IssuanceOfCommonStocksFromRsuVesting" name="IssuanceOfCommonStocksFromRsuVesting" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_LegacyQ32Member" name="LegacyQ32Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ConvertibleNotesMember" name="ConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_BusinessCombinationSharesConversionIntoRightsToPurchaseCommonStock" name="BusinessCombinationSharesConversionIntoRightsToPurchaseCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_EventDomain" name="EventDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PaymentOnVentureDebt" name="PaymentOnVentureDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_ConsultingAndAdvisoryAgreementsMember" name="ConsultingAndAdvisoryAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ScheduleOfIncomeTaxesPaidTableTextBlock" name="ScheduleOfIncomeTaxesPaidTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_IssuanceOfCommonStockToAmgenValue" name="IssuanceOfCommonStockToAmgenValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_ConvertibleDebtAgreementMember" name="ConvertibleDebtAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_SalesBasedMilestoneMember" name="SalesBasedMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PeriodDomain" name="PeriodDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTable" name="DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersReverseRecapitalization" name="StockIssuedDuringPeriodValueToHomologyShareholdersReverseRecapitalization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_MergerAndAcquisitionLineItems" name="MergerAndAcquisitionLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
</xsd:schema>
