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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="us-gaap_AccountingPoliciesAbstract"/>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TaxCreditCarryforwardNameDomain" xlink:label="us-gaap_TaxCreditCarryforwardNameDomain"/>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_HomologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Homology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_HomologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Homology [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_HomologyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Homology.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommercialMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commercial milestone payment payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommercialMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commercial Milestone Payment Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommercialMilestonePaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commercial milestone payment payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Research And Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Policies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accounting policies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Reserve</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restructuring Reserve, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Accrued restructuring , Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Accrued restructuring , Ending Balance</link:label>
          <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/terseLabel">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="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="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/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/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/terseLabel">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/label">Increase (Decrease) in 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/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_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="qttb_PreFundedWarrantsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre Funded Warrants Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre Funded Warrants Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, after Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee Operating Lease Liability Payments Due After Year Four</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_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_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="us-gaap_EquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Abstract]</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/label">Nature Of Business [Line Items]</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="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_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_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_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="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="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="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_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_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="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/verboseLabel">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/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/documentation">Upon receipt of waiver of milestone conditions.</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/terseLabel">Preferred stock shares outsstanding</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/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/periodStartLabel">Beginning balance, Shares</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="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/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/documentation">Series A One Convertible Preferred Stock.</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_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_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_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/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/terseLabel">Cash and 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/label">Tranche [Domain]</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="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="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="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/verboseLabel">Common stock shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TransactionCostsRelatedToReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction costs related to reverse recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TransactionCostsRelatedToReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction costs related to reverse recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TransactionCostsRelatedToReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs related to reverse recapitalization included in accounts payable and accrued expenses</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_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/terseLabel">Proceeds from 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/label">Proceeds from Issuance of 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="qttb_SalesAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sales Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SalesAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sales 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_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/documentation">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/label">Temporary Equity [Member]</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_AmountsDueUnderAssetPurchaseAgreementCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amounts Due Under Asset Purchase Agreement Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AmountsDueUnderAssetPurchaseAgreementCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amounts Due Under Asset Purchase Agreement Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AmountsDueUnderAssetPurchaseAgreementCurrent_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="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>
          <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="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/documentation">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/verboseLabel">Warrants to purchase common stock [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/label">Warrant [Member]</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/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/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/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</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/2009/role/negatedLabel">Less current portion</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_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_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_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_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_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/terseLabel">Operating lease expiration 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/documentation">Lease expiration date year and month.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring and Related Costs [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Restructuring Liability Related to the Restructuring Plan</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="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/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_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_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/verboseLabel">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/label">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/label">Cash Consideration [Member]</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="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/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_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_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/terseLabel">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/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/documentation">Warrants issued to silicon valley bank.</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/terseLabel">Related Party</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_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="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="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="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="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_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_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_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_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="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="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_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/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="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="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/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_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of calculation of diluted net income (loss) per share, the numerator is adjusted for any changes</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/terseLabel">Net 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/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="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="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="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_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/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_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted-average grant date fair value, options granted</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/terseLabel">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/terseLabel">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/documentation">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/terseLabel">Debt and Warrant Issuance Costs</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_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="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="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="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/documentation">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">2029</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="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="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="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/documentation">Agreement.</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:</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/terseLabel">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/label">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/totalLabel">Retained Earnings (Accumulated Deficit), Total</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/label">Retained Earnings (Accumulated Deficit)</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="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_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Shares, Cancelled</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/negatedTerseLabel">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/terseLabel">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/documentation">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">Sale of stock issue price per share</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_SaleOfStockPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">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/terseLabel">Total intrinsic value of options exercised</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="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="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="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_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_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_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_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/terseLabel">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/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/documentation">Waltham massauchets.</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="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/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="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_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_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="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="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="qttb_IssuanceOfCommonStockAndPrefundedWarrantsInRegisteredDirectOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Common Stock And Prefunded Warrants In Registered Direct Offering Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPrefundedWarrantsInRegisteredDirectOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance Of Common Stock And Prefunded Warrants In Registered Direct Offering Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPrefundedWarrantsInRegisteredDirectOfferingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock and pre-funded warrants in Registered Direct Offering, net of issuance costs</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/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="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_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Loss per Share Attributable to Common Stockholders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Policy [Policy Text Block]</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="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/documentation">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/label">Liabilities and Equity [Abstract]</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 and stockholders' equity</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/totalLabel">Net cash used in operating activities</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_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="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="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_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_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_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_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_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/2003/role/documentation">Change In Fair Value Of Equity Investment</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="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/documentation">Measurement input 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/terseLabel">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/label">Common Stock [Member]</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/2009/role/negatedLabel">Gain on convertible notes</link:label>
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          <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_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_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/2009/role/negatedLabel">Less accumulated depreciation</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>
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          <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/documentation">Tranche two milestone.</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>
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          <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="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="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
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          <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>
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          <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="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
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          <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>
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          <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/terseLabel">Income Taxes</link:label>
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          <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>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeneficiallyOwnPercentageOfNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Beneficially Own Percentage Of Number Of Shares.</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="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="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_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sales of Business, Affiliate and Productive Assets</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/terseLabel">Amount received on sales of asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net increase (decrease) in cash, cash equivalents, restricted cash and restricted cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Excluding Exchange Rate Effect, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommitmentAndContingenciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitment And Contingencies [Line Items]</link:label>
          <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_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/terseLabel">Stock-based compensation expense</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_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_IncentiveFromLessor_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Incentive from Lessor</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/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/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/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/terseLabel">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/label">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/totalLabel">Total other comprehensive gain (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/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="qttb_PaymentOnVentureDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal payments on venture debt</link:label>
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          <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="us-gaap_ProceedsFromIssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross proceeds of warrants</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="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/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/documentation">Series B Convertible Preferred Stock.</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="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="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="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/documentation">Convertible debt agreement.</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_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_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_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_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/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/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/totalLabel">Debt Securities, Available-for-Sale, Amortized Cost, Total</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_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="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="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="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/documentation">Series a one redeemable convertible preferred stock.</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>
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          <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_DeferredTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeferredTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred transaction costs included in accrued expenses and other current liabilities</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/terseLabel">Total accrued expenses and other current liabilities</link:label>
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          <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>
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          <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>
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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/verboseLabel">Restricted cash equivalents</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Quarterly Report</link:label>
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          <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>
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          <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_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="qttb_CollaborationAgreementContingentPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration Agreement Contingent Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CollaborationAgreementContingentPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration agreement contingent payment.</link:label>
          <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>
          <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_FinancialLiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of warrants issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Liabilities Fair Value Disclosure</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_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_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/terseLabel">Research and Development Expenses</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_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/terseLabel">Dilutive securities</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_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/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="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/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="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/terseLabel">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/label">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/terseLabel">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/label">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/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="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="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_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_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_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_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_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of deferred 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/totalLabel">Increase (Decrease) in Notes Payable, Current, Total</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_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_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_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_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_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/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_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/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/terseLabel">Issuance of common stock 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_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other noncurrent assets</link:label>
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          <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_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_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_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/verboseLabel">Tranche One [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/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/documentation">Tranche one milestone.</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_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_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_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Interest expenses on convertible debt</link:label>
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          <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>
          <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_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/documentation">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/terseLabel">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/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/documentation">Restricted cash and cash equivalents non current.</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>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesARedeemablePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">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/label">Nature Of Business [Table]</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="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_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_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="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 March 31, 2026 and December 31, 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre Funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre Funded Warrants [Member]</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="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/documentation">Operating lease assets lessee [Abstract].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeterminationOfFairValueOfCommonStockOnGrantDatesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Determination of Fair Value of Common Stock on Grant Dates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeterminationOfFairValueOfCommonStockOnGrantDatesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Determination Of Fair Value Of Common Stock On Grant Dates [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DeterminationOfFairValueOfCommonStockOnGrantDatesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Determination of fair value of common stock on grant dates.</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="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="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/terseLabel">Current assets:</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="qttb_ATMOfferingProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ATM Offering Program [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ATMOfferingProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">ATM Offering Program [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="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="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="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/documentation">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/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, net</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_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/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="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="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_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/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="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="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="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="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="us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restructuring Charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring and Related Activities Disclosure [Text Block]</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/periodStartLabel">Beginning 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/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/label">Shares, Outstanding</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/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/totalLabel">Restricted Cash and Cash Equivalents, Total</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 10)</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="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="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="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/documentation">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/verboseLabel">Total 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/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/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/label">Operating 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/verboseLabel">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/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/documentation">Series b redeemable convertible preferred stock.</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_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_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="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="srt_ScenarioForecastMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forecast</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_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="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/documentation">Amount of 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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsAndShortTermInvestmentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, and Short-Term Investment [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsAndShortTermInvestmentsTextBlock_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_InvestmentMaturityTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Investment Maturity Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_InvestmentMaturityTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Maturity Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_InvestmentMaturityTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contractual maturity date of investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Income (Expense), Operating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Income (Expense), Operating, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalExpendituresIncurredButNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest payments on venture debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalExpendituresIncurredButNotYetPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital Expenditures Incurred but Not yet Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Recognized Amount [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted Average Number of Shares Outstanding, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted-average common shares outstanding-basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average common shares - basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementScenarioAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate Intrinsic Value, Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre Funded Warrant [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre Funded Warrant table</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of reconciliation of income tax expense (benefit) computed</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options granted</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OfferingPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Offering Price</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre Funded Warrants TextBlock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre Funded Warrants TextBlock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre Funded Warrants</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="qttb_AccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accounting policies.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RevenueUsedToDetermineTransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction price to be determined</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RevenueUsedToDetermineTransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Used To Determine Transaction Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RevenueUsedToDetermineTransactionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue used to determine transaction price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NumberOfCommonStockUnderlyingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Common Stock Underlying Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NumberOfCommonStockUnderlyingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of Common Stock Underlying Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_NumberOfCommonStockUnderlyingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of common stock underlying shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedResearchAndDevelopmentExpensesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued external research and development</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedResearchAndDevelopmentExpensesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued research and development expenses current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Assumed in Reverse Recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Assumed in Reverse Recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares, Assumed in reverse recapitalization</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Name [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Equity Method Investments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesARedeemableConvertiblePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A Redeemable Convertible Preferred Stock [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyAndTwoThousandAndTwentyThreeTermALoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Two Thousand And Twenty And Two Thousand And Twenty Three Term A Loan [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyAndTwoThousandAndTwentyThreeTermALoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand and twenty and two thousand and twenty three term a loan.</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/periodStartLabel">Beginning balance</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/label">CVR Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CvrLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">CVR liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SalesBasedMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">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>
          <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="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtFairValueDisclosures_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Convertible debt at fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtFairValueDisclosures_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible debt, fair value disclosures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtFairValueDisclosures_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt, Fair Value Disclosures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Pre-FundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre-funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Pre-FundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre-funded Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Pre-FundedWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre-funded warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AreaOfRealEstateProperty_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Office space leased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AreaOfRealEstateProperty_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Area of Real Estate Property</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertibleNotesPolicyTextBlock_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_ConvertibleNotesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertibleNotesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible notes.</link:label>
          <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_BusinessCombinationStepAcquisitionEquityInterestInAcquireeIncludingSubsequentAcquisitionPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Achieved in Stages, Preacquisition and Acquired Equity Interests in Acquiree, Percentage</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/terseLabel">Cash FDIC insured amount</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>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating segment</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteSpinoffTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note, Spinoff Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteSpinoffTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reverse recapitalization transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal amount of term loans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandSeventeenStockOptionAndGrantPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Seventeen Stock Option and Grant Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandSeventeenStockOptionAndGrantPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand seventeen stock option and grant plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandSeventeenStockOptionAndGrantPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2017 Stock Option and Grant Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Before Thirty First Of March Two Thousand And Twenty Six [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Before Thirty First Of March Two Thousand And Twenty Six [Member]</link:label>
          <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>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfPrepaidExpensesAndOtherCurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Prepaid Expenses And Other Current Assets [Table Text Block]</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfPrepaidExpensesAndOtherCurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Prepaid Expenses and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_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, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares, Vested and expected to vest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_VentureDebtTwoThousandTwentyAndTwoThousandAndTwentyThreeTermALoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Venture Debt Two Thousand Twenty And Two Thousand And Twenty Three Term A Loan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_VentureDebtTwoThousandTwentyAndTwoThousandAndTwentyThreeTermALoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Venture debt two thousand twenty and two thousand and twenty three term a loan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_VentureDebtTwoThousandTwentyAndTwoThousandAndTwentyThreeTermALoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Venture Debt Two Thousand Twenty And Two Thousand And Twenty Three Term A Loan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentOfReverseRecapitalizationTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment Of Reverse Recapitalization Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentOfReverseRecapitalizationTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of Reverse Recapitalization Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentOfReverseRecapitalizationTransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of reverse recapitalization transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LicenseAgreementWithTheUniversityOfColoradoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement With The University Of Colorado [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LicenseAgreementWithTheUniversityOfColoradoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License agreement with the university of colorado.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LicenseAgreementWithTheUniversityOfColoradoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License Agreement With The University Of Colorado [Member]</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>
          <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_MergerAndAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of information about merger and acquisition.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MergerAndAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Merger and Acquisition [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MeasurementInputTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Input Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note [Abstract]</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/terseLabel">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/label">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/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/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/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/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/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/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/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/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_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/verboseLabel">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/totalLabel">Total current assets</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_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_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_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="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="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/terseLabel">AA phase 2 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/documentation">AA phase two 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/terseLabel">Issuance of common stock in the pre-closing financing, Shares</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="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
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          <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/terseLabel">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/documentation">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/terseLabel">Number of Shares, Exercisable</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_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_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_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="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="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_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/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_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="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="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 [Member]</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/terseLabel">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/documentation">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/terseLabel">Liabilities:</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/documentation">Operating lease liabilities lessee [Abstract].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPrefundedWarrantsInRegisteredDirectOfferingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Common Stock And Prefunded Warrants In Registered Direct Offering Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPrefundedWarrantsInRegisteredDirectOfferingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance Of Common Stock And Prefunded Warrants In Registered Direct Offering Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPrefundedWarrantsInRegisteredDirectOfferingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock and pre-funded warrants in Registered Direct Offering, net of issuance costs, Shares</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_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/verboseLabel">Number of shares purchase</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_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_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/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_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/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_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="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/documentation">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/verboseLabel">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/label">Class of Stock [Axis]</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/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_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/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_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="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/documentation">Seventh amendment to the loan agreement.</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="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="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="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/documentation">Restricted cash non current.</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_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_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="us-gaap_RestructuringAndRelatedCostIncurredCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring and Related Cost, Incurred Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringAndRelatedCostIncurredCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expenses incurred</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/terseLabel">Shares reserved upon the conversion of authorized Series A preferred stock [Member]</link:label>
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          <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="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Deferred Revenue</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="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/documentation">Two thousand and twenty three term a loan advance.</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_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_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/terseLabel">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/documentation">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/terseLabel">Scenario two [Member]</link:label>
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          <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_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="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="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">Restricted Stock [Member]</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>
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          <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/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="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="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="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/terseLabel">Expected stock price volatility range, 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/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_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/totalLabel">Total 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/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/label">Prepaid Expense and Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrincipalAmountOutstandingOnLoansSecuritized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan, Securitized or Asset-Backed Financing Arrangement, Principal Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrincipalAmountOutstandingOnLoansSecuritized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal Amount Outstanding</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="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/documentation">Scenario one member.</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_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/documentation">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/terseLabel">Collaboration agreement, Aggregate amount of sales milestone</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/documentation">Collaborative arrangement milestone payments.</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/verboseLabel">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/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/documentation">License agreement with bristol mayers equib company.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</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_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_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="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="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_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/documentation">AD phase two 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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLiquidationPreference_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock liquidation preference</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLiquidationPreference_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Liquidation Preference</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="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/documentation">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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issued during period</link:label>
          <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="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Price</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_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/documentation">Loan and security fifth amendment agreement with silicon valley bank.</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="us-gaap_RestructuringCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restructuring Charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restructuring Charges, Total</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/terseLabel">Estimated Useful Life (Years)</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="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="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="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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</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="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/documentation">Before thirty first of march two thousand and twenty four.</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_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_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_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_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_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="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="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/documentation">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/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="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="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="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/documentation">Loan and security agreement with silicon valley bank.</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>
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          <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_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 liabilities</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/terseLabel">Transaction Price</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="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_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_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_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_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_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&#160;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/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/terseLabel">Research and development</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestructuringChargesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restructuring Charges [Abstract]</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 provision for income taxes</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/terseLabel">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/label">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>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Stock Option Activity</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="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/documentation">Loan and security third amendment agreement with silicon valley bank.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Loss per Share</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_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_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_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_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="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_SaleOfStockConsiderationReceivedPerTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares sold received amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockConsiderationReceivedPerTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Consideration Received Per Transaction</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/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/2003/role/totalLabel">Net loss and comprehensive loss</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_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value</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/periodEndLabel">Aggregate Intrinsic Value, Outstanding Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ResearchAndDevelopmentTaxIncentivePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and Development Tax Incentive</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ResearchAndDevelopmentTaxIncentivePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Tax Incentive [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ResearchAndDevelopmentTaxIncentivePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research and development tax incentive.</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/terseLabel">Fixed lease costs</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ChangeInFairValueOfConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Change in Fair Value Of Convertible Notes</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ChangeInFairValueOfConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Change in fair value of convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ChangeInFairValueOfConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in fair value of convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class of warrants or rights term</link:label>
          <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>
          <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="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="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="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/documentation">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/2009/role/negatedLabel">Prepaid expenses and other current assets</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_AmortizationOfFinancingCostsAndDiscounts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of debt discount and issuance costs</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/label">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/terseLabel">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Measurement Input</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMeasurementInput_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, measurement input</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>
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          <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_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</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_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of loss from operations before income taxes</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/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/terseLabel">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 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>
          <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_FairValueDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrentAndNoncurrent_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="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reverse recapitalization transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Available to Common Stockholders, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net income (loss) attributable to common stockholders- basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Income (Loss) Available to Common Stockholders, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net loss -basic</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="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="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/terseLabel">Thereafter</link:label>
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          <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/totalLabel">Assets, Fair Value Disclosure, Total</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="qttb_DevelopmentAndRegulatoryMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development and regulatory milestones</link:label>
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          <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="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Axis]</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>
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          <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_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/verboseLabel">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/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/documentation">Series a two redeemable convertible preferred stock.</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, Cancelled</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/2009/role/negatedLabel">Weighted- Average Exercise Price, Cancelled</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/verboseLabel">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/terseLabel">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/label">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/terseLabel">Income Taxes</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_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Table]</link:label>
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          <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="dei_DocumentInformationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Information [Table]</link:label>
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          <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>
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          <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/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_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
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          <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/terseLabel">Risk-free interest rate range, 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/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="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/terseLabel">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/documentation">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/terseLabel">Accrued compensation and related expenses</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_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_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_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_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_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_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_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_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_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/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/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/totalLabel">Total minimum lease payments</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_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_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/verboseLabel">Line of credit facility outstanding 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/label">Line of Credit, 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</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="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/documentation">Prepaid external research and development current.</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="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_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_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/terseLabel">Convertible debt interest rate percentage</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_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="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="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="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/documentation">Event.</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/verboseLabel">Share based awards, maximum contractual term</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_CollaborativeArrangementAccountingPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration Arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementAccountingPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement, Accounting Policy [Policy Text Block]</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/label">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/terseLabel">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/terseLabel">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/documentation">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/terseLabel">Accrued professional services and other</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/documentation">Accrued professional fees and other accrued liabilities current.</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/terseLabel">Weighted- Average Exercise Price, Exercised</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_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="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_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, 14,629,463 and 12,858,047 shares issued and outstanding at March 31, 2026 and December 31, 2025, 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/terseLabel">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/documentation">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/terseLabel">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/label">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 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/terseLabel">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/label">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/terseLabel">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/documentation">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/terseLabel">Transaction as an asset 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/label">Increase (Decrease) in Asset, Held-for-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/terseLabel">Principles of Consolidation</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_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_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_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/terseLabel">Impairment of Long-Lived Assets</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="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="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/documentation">Current liabilities lessee [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/terseLabel">Received amount from Horizon</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_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/label">Disclosure in tabular form of venture debt [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="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/terseLabel">Debt</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="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_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_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="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/documentation">Non current liabilities lessee [Abstract].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherDeferredCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Deferred Costs, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherDeferredCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Deferred Costs, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherDeferredCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred transaction costs</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="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_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/documentation">Royalty as a percentage of net 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/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/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/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/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_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income</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_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="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="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/documentation">Disclosure in entirety of temporary equity.</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_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_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/terseLabel">Tranche Three [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/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/documentation">Tranche three milestone.</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/2009/role/negatedLabel">Provision for income taxes</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 provision</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Provision for tax expense (benefit)</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">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/terseLabel">Measurement Frequency</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="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/terseLabel">Estimated Useful Life (Years)</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>
          <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="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from issuance of common stock and pre-funded warrants in Registered Direct Offering, net of issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock to Homology shareholders in reverse recapitalization, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Issued During Period Value to Homology Shareholders in Reverse Recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersInReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Value to Homology Shareholders in Reverse Recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Fair Value Measurement Significant Inputs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentrations of Credit Risk and Significant Suppliers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationRelatedCostsPolicyTextBlock_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_CompensationRelatedCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Compensation Related Costs, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MergerAndAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Merger and Acquisition [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MergerAndAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Merger and Acquisition [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MergerAndAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Merger and Acquisition [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertiblePreferredStockPolicyTextBlock_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="qttb_ConvertiblePreferredStockPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Preferred Stock [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ConvertiblePreferredStockPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible preferred stock.</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromCollaborativeArrangementExcludingRevenueFromContractWithCustomer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Collaborative Arrangement, Excluding Revenue from Contract with Customer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRestructuring_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRestructuring_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Restructuring</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRestructuring_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityByClassOfStockTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, by Class of Stock [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net assets acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table]</link:label>
          <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_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReclassificationsOfTemporaryToPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary equity converted into permanent equity value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReclassificationsOfTemporaryToPermanentEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reclassifications of Temporary to Permanent Equity</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ExcessOfAccruedRightToPurchaseStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Excess of accrued right to purchase stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ExcessOfAccruedRightToPurchaseStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Excess of accrued right to purchase stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Number of Shares Issued in Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares sold</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/terseLabel">Stock issued during the period new issues</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock issued during the period new issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ProceedsFromReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from Reverse Recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ProceedsFromReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Reverse Recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ProceedsFromReverseRecapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash acquired in connection with reverse recapitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss per share - diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income (loss) per share-diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Diluted, Total</link:label>
          <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="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Segment Reporting Information by Segment</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>
          <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/documentation">Collaboration agreement transaction price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommercialMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commercial Milestones Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommercialMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commercial Milestones Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_CommercialMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commercial milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLifeDescriptionOfTermExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandTwentyFourStockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Thousand Twenty Four Stock Option and Incentive Plan [Member]</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandTwentyFourStockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2024 Stock Option and Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCvrAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance Of CVR At Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCvrAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of CVR At Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCvrAtFairValue_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_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred, Liabilities Incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PrepaidExternalResearchAndDevelopmentNonurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid external research and development - long term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PrepaidExternalResearchAndDevelopmentNonurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">prepaid external research and development nonurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PrepaidExternalResearchAndDevelopmentNonurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">prepaid external research and development nonurrent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LineOfCreditFacilityAmountThatMayBeContingentlyBorrowed_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility amount that may be contingently borrowed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LineOfCreditFacilityAmountThatMayBeContingentlyBorrowed_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line Of Credit Facility Amount That May Be Contingently Borrowed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LineOfCreditFacilityAmountThatMayBeContingentlyBorrowed_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Line of credit facility amount that may be contingently borrowed.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument face value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Face Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit maximum borrowing capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Maximum Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Rule 10b5-1 Arr Modified [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Rule 10b5-1 Arrangement Modified [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_Rule10B51ArrModifiedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Rule 10b5-1 Arrangement Modified</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="qttb_HorizonTherapeuticsIrelandDacMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">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/label">Horizon Therapeutics Ireland DAC [Member]</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="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="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/documentation">Loan and security second amendment agreement with silicon valley bank.</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="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="qttb_PreFundedWarrantsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre Funded Warrants [Line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre Funded Warrants [Line items]</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="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/documentation">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/terseLabel">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/label">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/totalLabel">Total lease costs</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="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/terseLabel">Long term debt variable interest rate percentage</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_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="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/label">Property, Plant and Equipment, Net</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">Loss from operations</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_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_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_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_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_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_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_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="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="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="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/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/documentation">Series A Convertible Preferred Stock.</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_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_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_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/label">Operating Lease, Liability, Noncurrent</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_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_ClassOfStockLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Line Items]</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 financing activities</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_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/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_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_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="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_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_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_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/terseLabel">Oxb Solutions</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="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/terseLabel">Lessee, operating lease, lease not yet commenced, renewal term</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from operating activities:</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Furniture and fixtures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Furniture and Fixtures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LineOfCreditFacilityAggregateAmountIncludingBalloonRepaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit facility aggregate amount including balloon repayment payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LineOfCreditFacilityAggregateAmountIncludingBalloonRepaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line Of Credit Facility Aggregate Amount Including Balloon Repayment Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LineOfCreditFacilityAggregateAmountIncludingBalloonRepaymentPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Line of credit facility aggregate amount including balloon repayment payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amortization of premium on short-term investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of premium on short-term investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accretion (Amortization) of Discounts and Premiums, Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_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="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfVentureDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Long-term Debt Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfVentureDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure In Tabular Form Of Venture Debt [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclosureInTabularFormOfVentureDebtTableTextBlock_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="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Offering share price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AgreementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Agreement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AgreementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Agreement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AgreementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationAssetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Contingent Consideration, Asset, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationContingentConsiderationAssetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combination, intial consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OtherGAExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other G&amp;A expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_OtherGAExpenses_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="qttb_OtherGAExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other G&amp;A Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance or Sale of Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Proceeds from Issuance or Sale of Equity, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from Issuance or sale of equity</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognised compensation cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityConversionPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Temporary equity conversion price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityConversionPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity Conversion Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TemporaryEquityConversionPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Temporary equity conversion price per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentToHorizon_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment To Horizon</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentToHorizon_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment to Horizon</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentToHorizon_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment to horizon</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Policies [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Number of Shares, Par Value and Other Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyTermALoanAdvanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Two Thousand And Twenty Term A Loan Advance [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyTermALoanAdvanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand And Twenty Term A Loan Advance [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyTermALoanAdvanceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand and twenty term a loan advance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SixthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Sixth Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SixthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sixth Amendment Agreement With Silicon Valley Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SixthAmendmentAgreementWithSiliconValleyBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sixth amendment agreement with silicon valley bank.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermLineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Venture debt, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermLineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Line of Credit, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</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/label">Class of Stock [Domain]</link:label>
          <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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant</link:label>
          <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_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition</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/verboseLabel">Executive insurance reserve</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfStockByClassTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock, Class of Stock [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityEmergingGrowthCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Emerging Growth Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1_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 Remaining Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Remaining Contractual Term, Vested and expected to vest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxCreditCarryforwardNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Credit Carryforward, Name [Domain]</link:label>
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  <xsd:element id="qttb_PropertyPlantAndEquipmentUsefulLife1" name="PropertyPlantAndEquipmentUsefulLife1" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_AchievementOfSpecifiedMilestonesMember" name="AchievementOfSpecifiedMilestonesMember" 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalization" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalization" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_CommitmentAndContingenciesLineItems" name="CommitmentAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_BeneficiallyOwnPercentageOfNumberOfShares" name="BeneficiallyOwnPercentageOfNumberOfShares" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_DeferredTransactionCosts" name="DeferredTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_TwoThousandSeventeenStockOptionAndGrantPlanMember" name="TwoThousandSeventeenStockOptionAndGrantPlanMember" 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_EstimatedAggregateProceedsFromDebtAndEquity" name="EstimatedAggregateProceedsFromDebtAndEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_Pre-FundedWarrantsMember" name="Pre-FundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_NumberOfDirectorsEntitledToBeElected" name="NumberOfDirectorsEntitledToBeElected" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_SalesAgreementMember" name="SalesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_SeriesARedeemableConvertiblePreferredStockMember" name="SeriesARedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CommercialMilestonesReceivable" name="CommercialMilestonesReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_OxbSolutionsMember" name="OxbSolutionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_SeriesATwoRedeemableConvertiblePreferredStockMember" name="SeriesATwoRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LicenseAgreementWithTheUniversityOfColoradoMember" name="LicenseAgreementWithTheUniversityOfColoradoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ConversionOfTemporaryEquityIntoPermanentEquityShares" name="ConversionOfTemporaryEquityIntoPermanentEquityShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_SeventhAmendmentToTheLoanAgreementMember" name="SeventhAmendmentToTheLoanAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" name="LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_PreFundedWarrantsAbstract" name="PreFundedWarrantsAbstract" type="xbrli:stringItemType" 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_IncomeTaxDisclosureTable" name="IncomeTaxDisclosureTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" 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_ATMOfferingProgramMember" name="ATMOfferingProgramMember" 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_PreFundedWarrantsLineItems" name="PreFundedWarrantsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LongTermDebtPercentageBearingAnnualyPrimeRate" name="LongTermDebtPercentageBearingAnnualyPrimeRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_IssuanceOfCommonStockAndPrefundedWarrantsInRegisteredDirectOfferingShares" name="IssuanceOfCommonStockAndPrefundedWarrantsInRegisteredDirectOfferingShares" type="xbrli:sharesItemType" 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_AgreementDomain" name="AgreementDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_DiscoveryAndOtherMember" name="DiscoveryAndOtherMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_PersonnelRelatedCostsExcludingStockBasedCompensation" name="PersonnelRelatedCostsExcludingStockBasedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_HomologyMember" name="HomologyMember" 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_LossOnImpairmentOfEquityInvestment" name="LossOnImpairmentOfEquityInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_AccountingPoliciesLineItems" name="AccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_SummaryOfPrepaidExpensesAndOtherCurrentAssetsTableTextBlock" name="SummaryOfPrepaidExpensesAndOtherCurrentAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_TwoThousandAndTwentyThreeTermALoanAdvanceMember" name="TwoThousandAndTwentyThreeTermALoanAdvanceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_DisclosureInTabularFormOfVentureDebtLineItems" name="DisclosureInTabularFormOfVentureDebtLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ResearchAndDevelopmentTaxIncentivePolicyTextBlock" name="ResearchAndDevelopmentTaxIncentivePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_DevelopmentAndSalesMilestonePaymentPayable" name="DevelopmentAndSalesMilestonePaymentPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_OperatingLeaseAssetsLesseeAbstract" name="OperatingLeaseAssetsLesseeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_IncreaseInNumberOfSharesReservedForIssuancePercentOfCommonStockOutstanding" name="IncreaseInNumberOfSharesReservedForIssuancePercentOfCommonStockOutstanding" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_IncomeTaxDisclosureLineItems" name="IncomeTaxDisclosureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock" name="AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_SeriesAOneRedeemableConvertiblePreferredStockMember" name="SeriesAOneRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AmountsDueUnderAssetPurchaseAgreementCurrent" name="AmountsDueUnderAssetPurchaseAgreementCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentySixMember" name="BeforeThirtyFirstOfMarchTwoThousandAndTwentySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_InvestmentMaturityTerm" name="InvestmentMaturityTerm" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_PreFundedWarrantsMember" name="PreFundedWarrantsMember" type="dtr-types:domainItemType" 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_NonRule10B51ArrModifiedFlag" name="NonRule10B51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_ConvertibleDebtAgreementMember" name="ConvertibleDebtAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_UponTheConversionOfAuthorizedSeriesBRedeemableConvertiblePreferredStockMember" name="UponTheConversionOfAuthorizedSeriesBRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" 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_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalizationWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsAssumedInReverseRecapitalizationWeightedAverageExercisePrice" type="dtr-types:perShareItemType" 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_NonCurrentLiabilitiesLesseeAbstract" name="NonCurrentLiabilitiesLesseeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PreFundedWarrantTable" name="PreFundedWarrantTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" 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_InvestmentsDisclosureAbstract" name="InvestmentsDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ConvertiblePreferredStockPolicyTextBlock" name="ConvertiblePreferredStockPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_MergerAndAcquisitionTable" name="MergerAndAcquisitionTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CurrentLiabilitiesLesseeAbstract" name="CurrentLiabilitiesLesseeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts" name="IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_UpfrontPaymentMade" name="UpfrontPaymentMade" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_AgreementAxis" name="AgreementAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" 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_RestrictedCashNonCurrentMember" name="RestrictedCashNonCurrentMember" type="dtr-types:domainItemType" 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_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTable" name="DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" 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_CollaborationAgreementContingentPaymentPayableExcessOfCashReceived" name="CollaborationAgreementContingentPaymentPayableExcessOfCashReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_DevelopmentAndRegulatoryMilestonesReceivable" name="DevelopmentAndRegulatoryMilestonesReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_ConvertibleNotesMember" name="ConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_BeforeThirtyFirstOfMarchTwoThousandAndTwentyFiveMember" name="BeforeThirtyFirstOfMarchTwoThousandAndTwentyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_RestrictedCashAndCashEquivalentsNonCurrentMember" name="RestrictedCashAndCashEquivalentsNonCurrentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_WalthamMassauchetsMember" name="WalthamMassauchetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_ScenarioThreeMember" name="ScenarioThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersInReverseRecapitalization" name="StockIssuedDuringPeriodValueToHomologyShareholdersInReverseRecapitalization" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_PhaseDomain" name="PhaseDomain" 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_DeterminationOfFairValueOfCommonStockOnGrantDatesPolicyTextBlock" name="DeterminationOfFairValueOfCommonStockOnGrantDatesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_AccruedProfessionalFeesAndOtherAccruedLiabilitiesCurrent" name="AccruedProfessionalFeesAndOtherAccruedLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_SeriesBRedeemableConvertiblePreferredStockMember" name="SeriesBRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" 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_BempikibartMember" name="BempikibartMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_DevelopmentMilestonePaymentPayable" name="DevelopmentMilestonePaymentPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_PaymentOnVentureDebt" name="PaymentOnVentureDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_EventAxis" name="EventAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" 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_ADPhaseTwoResearchServicesMember" name="ADPhaseTwoResearchServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_PercentageOfSublicenseFees" name="PercentageOfSublicenseFees" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_CvrLiability" name="CvrLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_Rule10B51ArrModifiedFlag" name="Rule10B51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_BeforeThirtyFirstOfMarchTwoThousandAndTwentyFourMember" name="BeforeThirtyFirstOfMarchTwoThousandAndTwentyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LoanAndSecurityAgreementWithSiliconValleyBankMember" name="LoanAndSecurityAgreementWithSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PhaseAxis" name="PhaseAxis" 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_TrancheThreeMilestoneMember" name="TrancheThreeMilestoneMember" 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_DisclosureInEntiretyOfTemporaryEquity" name="DisclosureInEntiretyOfTemporaryEquity" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock" name="ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
