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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet"/>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationLineItems" xlink:label="dei_DocumentInformationLineItems"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingAbstract" xlink:label="us-gaap_SegmentReportingAbstract"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:label="us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsCurrent" xlink:label="us-gaap_OtherAssetsCurrent"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressPostalZipCode" xlink:label="dei_EntityAddressPostalZipCode"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="us-gaap_StatementOfFinancialPositionAbstract"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LocalPhoneNumber" xlink:label="dei_LocalPhoneNumber"/>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_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_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="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_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="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="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="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="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_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accrued Expenses and Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accrued Liabilities [Table Text Block]</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_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="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="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Operating and Nonoperating</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_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="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_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_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_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="us-gaap_OtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone receivable upon the earlier of achievement of the first milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Receivables, Net, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Receivables, Net, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_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="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="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="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="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument effective rate of interest percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Effective Percentage</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_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="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="qttb_PreFundedWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Pre Funded Warrant Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PreFundedWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Pre Funded Warrant Liability</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="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_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_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>
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          <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_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AssetPurchaseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Purchase Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AssetPurchaseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset Purchase Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AssetPurchaseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Purchase Agreement</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_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Provision for income taxes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/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_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="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="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_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_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units (RSUs) [Member]</link:label>
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          <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_IssuanceOfCommonStockPursuantToAt-The-MarketOfferingNetOfDiscountsAndIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock Pursuant to At-the-Market Offering, Net of Discounts and Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockPursuantToAt-The-MarketOfferingNetOfDiscountsAndIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock Pursuant to At-the-Market Offering, Net of Discounts and Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockPursuantToAt-The-MarketOfferingNetOfDiscountsAndIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock pursuant to at-the-market offering, net of discounts and issuance costs, shares</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_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Conversion of Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of convertible preferred stock to common stock in connection with the Merger, Value</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_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_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant, and Equipment [Text Block]</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="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="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressesAddressTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Addresses, Address Type [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">General and Administrative Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LegacyQ32Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Legacy Q32</link:label>
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          <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_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>
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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_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Stockholders' Equity [Abstract]</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="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="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_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign Currency Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Currency Transactions and Translations Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="us-gaap_TemporaryEquityDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity Disclosure [Abstract]</link:label>
          <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>
          <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="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="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_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_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 September 30, 2026 and December 31, 2025</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="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_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="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_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_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="srt_TitleOfIndividualWithRelationshipToEntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title and Position [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="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="us-gaap_ProceedsFromIssuanceOfPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Private Placement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common stock and pre-funded warrants in private placement, net of issuance costs</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_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_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>
          <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="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="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Domain]</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_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [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_TrancheTwoMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tranche Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability</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_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent</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="qttb_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourStockPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for future issuance under the 2024 Stock Incentive Plan</link:label>
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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="qttb_BeneficiallyOwnPercentageOfNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Beneficially Own Percentage Of Number Of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Carrying amount</link:label>
          <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="qttb_CommitmentAndContingenciesLineItems_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="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="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_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="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="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="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_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Options Exercised</link:label>
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          <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="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_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="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_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="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="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_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of options vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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_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_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Extinguishment of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gain (Loss) on Extinguishment of Debt, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Loss on extinguishment of venture debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss on extinguishment of debt</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_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="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_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common Stock Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nature of the Business</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfEstimatedUsefulLifeOfAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Estimated Useful Life Of Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SummaryOfEstimatedUsefulLifeOfAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of estimated useful life of assets.</link:label>
          <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_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="qttb_PayrollTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payroll tax credit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PayrollTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payroll tax credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PayrollTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payroll Tax Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MergersAndAquisitionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Mergers and Aquisitions Abstract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_MergersAndAquisitionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Mergers and Aquisitions [Abstract]</link:label>
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          <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="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
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          <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>
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          <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="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_EquityMethodInvestmentOwnershipPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment, Ownership Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentOwnershipPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity method investment, ownership, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentOwnershipPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Ownership Percentage</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="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="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInPrivatePlacementNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock and Pre-Funded Warrants in Private Placement, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInPrivatePlacementNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock and Pre-Funded Warrants in Private Placement, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInPrivatePlacementNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock and pre-funded warrants in private placement, net of issuance costs, Shares</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_ReceivableFromExerciseOfStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Receivable from exercise of stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReceivableFromExerciseOfStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivable from Exercise of Stock Options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ReceivableFromExerciseOfStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Receivable from Exercise of Stock Options</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_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in operating assets and liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="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="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_ClassOfWarrantOrRightOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants and Rights Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Pre-funded warrants to purchase</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_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_IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock in the pre-closing financing, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock During Period Pre-Closing Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock During Period Pre-Closing Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesARedeemablePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series A Redeemable Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesARedeemablePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series a redeemable preferred stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SeriesARedeemablePreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series A Redeemable Preferred Stock [Member]</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">Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization</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_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_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="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 Asset, Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Text Block]</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="us-gaap_OtherGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherGeneralAndAdministrativeExpense_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="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="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="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="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="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_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_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_LineOfCreditFacilityRemainingBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Line of credit remaining borrowing capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Remaining Borrowing Capacity</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="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_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="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_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_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>
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          <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_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="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="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_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_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Research and Development Expense, Total</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="us-gaap_ShareBasedArrangementsToObtainGoodsAndServicesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Assumptions Used to Value Stock Options Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of loss from operations before income taxes</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/label">Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]</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="srt_TitleOfIndividualAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title and Position [Axis]</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_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="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="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="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Use of Estimates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Use of Estimates, Policy [Policy Text Block]</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_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_ClassOfStockDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Class of Stock [Domain]</link:label>
          <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_AccountsPayableCurrent_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_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable, Current</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_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_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="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other noncurrent assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock and Pre-Funded Warrants in Follow-On Financing, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock and Pre-Funded Warrants in Follow-On Financing, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancingShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock and pre-funded warrants in Follow-On Financing, Shares</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="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_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclousreOfPrepaidExpensesOtherCurrentAssetsAndOtherNoncurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclousre Of Prepaid Expenses Other Current Assets and Other Noncurrent Assets [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclousreOfPrepaidExpensesOtherCurrentAssetsAndOtherNoncurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclousre of prepaid expenses other current assets and other noncurrent assets text block.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DisclousreOfPrepaidExpensesOtherCurrentAssetsAndOtherNoncurrentAssetsTextBlock_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_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_OfferingPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Offering Price</link:label>
          <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>
          <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_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_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_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>
          <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_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="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_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="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="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_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_BusinessCombinationSeparatelyRecognizedTransactionsRevenuesAndGainsRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsRevenuesAndGainsRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Separately Recognized Transactions, Revenues and Gains Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PayoffOfVentureDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payoff of venture debt</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PayoffOfVentureDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payoff of Venture Debt</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="qttb_RecognizedRemainingVestingTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Recognized Remaining Vesting Terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RecognizedRemainingVestingTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Recognized Remaining Vesting Terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_RecognizedRemainingVestingTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recognized Remaining Vesting Terms</link:label>
          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PropertyAndEquipmentAdditionsIncludedInAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property and Equipment Additions Included in Accrued Expenses and Other Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PropertyAndEquipmentAdditionsIncludedInAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Property and Equipment Additions Included in Accrued Expenses and Other Liabilities</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedResearchAndDevelopmentExpensesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Research And Development Expenses Current</link:label>
          <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="us-gaap_ProceedsFromSaleOfEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sale of equity method investments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PropertyAndEquipmentIncludeInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Property and Equipment include in Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PropertyAndEquipmentIncludeInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment additions included in accounts payable</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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_TwoThousandAndTwentyAndTwoThousandAndTwentyThreeTermALoanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand And 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_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_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>
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          <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_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_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock par value per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Net income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss and comprehensive 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 loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfLongLivedAssetsHeldForUse_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment, long-lived asset, held-for-use</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Lived Tangible Asset</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/totalLabel">Restricted Cash and Cash Equivalents, Noncurrent, Total</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_SalesBasedMilestoneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/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="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>
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          <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_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement Frequency</link:label>
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          <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>
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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="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_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Agreements with Horizon</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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="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="us-gaap_ScheduleOfCashCashEquivalentsAndShortTermInvestmentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, and Investment [Table Text Block]</link:label>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Text Block]</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>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock During Period Pre-Closing Financing, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockDuringPeriodPreClosingFinancingNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock During Period Pre-Closing Financing, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_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="srt_ChiefExecutiveOfficerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Chief Executive Officer [Member]</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_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_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="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="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_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_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options to purchase common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="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_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="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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_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="us-gaap_DeferredChargesPolicyTextBlock_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_DeferredChargesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Charges, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AssetsNotYetInUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets Not Yet In Use [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AssetsNotYetInUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Assets Not Yet In Use [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AssetsNotYetInUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets not yet in service [Member]</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>
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          <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="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Information</link:label>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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_OtherResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Research and Development Expense</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>
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          <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_LongTermDebtCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less current portion</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="us-gaap_EmployeeStockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares reserved for stock option exercises [Member]</link:label>
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          <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="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [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="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_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_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_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_StatementOfIncomeLocationBalanceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Location, Statement of Income, Balance [Axis]</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_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">Long-Lived Asset, Excluding Intangible Asset and Goodwill, Impairment and Disposal [Policy Text Block]</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_ShareBasedPaymentArrangementEmployeeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Employee [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedPaymentArrangementEmployeeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share Based Payment Arrangement Employee [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/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="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_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_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_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_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="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_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="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock from option exercises, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Shares, Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from issuance of common stock and pre-funded warrants in Follow-On Financing, net of issuance costs</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_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_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="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring and Nonrecurring [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions Disclosure [Text Block]</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_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_TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Including Noncontrolling Interest</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="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="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_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_ColoradoLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Colorado License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ColoradoLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Colorado License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_ColoradoLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Colorado License Agreement</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_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Significant Accounting Policies</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>
          <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_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="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_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_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="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>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Expenses and Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Expenses And Other Current Liabilities Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued expenses and other current liabilities disclosure.</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_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="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="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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_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_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="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="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="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_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="qttb_DevelopmentAndRegulatoryMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development and regulatory milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentAndRegulatoryMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Development and Regulatory Milestones Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_DevelopmentAndRegulatoryMilestonesReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Development and Regulatory Milestones Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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="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_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="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="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_EquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity method investments</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_LongTermDebtPercentageBearingAnnualyPrimeRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long Term Debt Percentage Bearing Annualy Prime Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LongTermDebtPercentageBearingAnnualyPrimeRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Long Term Debt Percentage Bearing Annualy Prime Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_LongTermDebtPercentageBearingAnnualyPrimeRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long term debt percentage bearing annual prime rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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="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_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_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="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_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="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_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_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="qttb_AccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Expenses And Other Liabilities Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Expenses And Other Liabilities Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_AccruedExpensesAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</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="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="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="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="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="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_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="us-gaap_ConsolidationPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principles of Consolidation</link:label>
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          <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_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_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="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of deferred taxes</link:label>
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          <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>
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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/label">Sale of Stock, Consideration Received on Transaction</link:label>
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          <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>
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          <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="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Shares, Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Shares, Outstanding, Ending Balance</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="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_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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_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="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_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="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_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="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_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_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recent Accounting Pronouncements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="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="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="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_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_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="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="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="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="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_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use asset, operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset</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="qttb_IssuanceOfCommonStockPursuantToAt-The-MarketOfferingNetOfDiscountsAndIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Common Stock Pursuant to At-the-Market Offering, Net of Discounts and Issuance Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockPursuantToAt-The-MarketOfferingNetOfDiscountsAndIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock Pursuant to At-the-Market Offering, Net of Discounts and Issuance Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockPursuantToAt-The-MarketOfferingNetOfDiscountsAndIssuanceCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock pursuant to at-the-market offering, net of discounts and issuance costs</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="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_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="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_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_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_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="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_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_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_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_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_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="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Comprehensive Loss</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>
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          <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_StockIssuedDuringPeriodSharesPurchaseOfAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock issued during period shares purchase of assets</link:label>
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          <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_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_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_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_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="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_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash and Cash Equivalents [Axis]</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="us-gaap_OtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Due to related parties</link:label>
          <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="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_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value per share</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_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_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="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_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="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_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="us-gaap_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leasehold improvements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leasehold Improvements [Member]</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_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase In Common Stock Capital Shares Reserved For Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase In Common Stock Capital Shares Reserved For Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in number of shares reserved for issuance (shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant, and Equipment, before Accumulated Depreciation, Depletion, and Amortization</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_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="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_PaymentsLessCertainContractualOffsets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments Less Certain Contractual Offsets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentsLessCertainContractualOffsets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payments Less Certain Contractual Offsets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_PaymentsLessCertainContractualOffsets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments less certain contractual offsets</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="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [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_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="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="us-gaap_AmortizationOfFinancingCostsAndDiscounts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Issuance Costs and Discounts</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, net of accrued interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Property Plant and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant, and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Measurements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement, Policy [Policy Text Block]</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_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_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="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Domain]</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="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="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="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_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental disclosure of non-cash operating, investing and financing activities:</link:label>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCashAndCashEquivalentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Cash and Cash Equivalents [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingOtherItemAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other segment items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingOtherItemAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Other Segment Item, Amount</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="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease weighted average remaining lease term</link:label>
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          <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>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancing_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Common Stock and Pre-Funded Warrants in Follow-On Financing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancing_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock and pre-funded warrants in Follow-On Financing</link:label>
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          <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>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Local Phone Number</link:label>
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  <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_StockIssuedDuringPeriodValueToHomologyShareholdersReverseRecapitalization" name="StockIssuedDuringPeriodValueToHomologyShareholdersReverseRecapitalization" 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_IssuanceOfCommonStockAndPre-FundedWarrantsInPrivatePlacementNetOfIssuanceCost" name="IssuanceOfCommonStockAndPre-FundedWarrantsInPrivatePlacementNetOfIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_SeriesBConvertiblePreferredStockMember" name="SeriesBConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PaymentsLessCertainContractualOffsets" name="PaymentsLessCertainContractualOffsets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_AnnualRentOperatingLeaseAggregateAfterIncrease" name="AnnualRentOperatingLeaseAggregateAfterIncrease" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock" name="ScheduleOfRecapitalizationOfAssetsAndLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancing" name="IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancing" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_ColoradoLicenseAgreementMember" name="ColoradoLicenseAgreementMember" 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_IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts" name="IssuanceOfCommonStockDuringPeriodPreClosingNetOfIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_IssuanceOfCommonStocksFromRsuVesting" name="IssuanceOfCommonStocksFromRsuVesting" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_DisclousreOfPrepaidExpensesOtherCurrentAssetsAndOtherNoncurrentAssetsTextBlock" name="DisclousreOfPrepaidExpensesOtherCurrentAssetsAndOtherNoncurrentAssetsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_IncreaseInNumberOfSharesReservedForIssuancePercentOfCommonStockOutstanding" name="IncreaseInNumberOfSharesReservedForIssuancePercentOfCommonStockOutstanding" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_OperatingLeaseLiabilitiesLesseeAbstract" name="OperatingLeaseLiabilitiesLesseeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TrancheOneMilestoneMember" name="TrancheOneMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_SeriesAConvertiblePreferredStockMember" name="SeriesAConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_CommonStockAtAPublicOffering" name="CommonStockAtAPublicOffering" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="qttb_CurrentLiabilitiesLesseeAbstract" name="CurrentLiabilitiesLesseeAbstract" type="xbrli:stringItemType" 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_ConsultingAndAdvisoryAgreementsMember" name="ConsultingAndAdvisoryAgreementsMember" 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_InvestmentsDisclosureAbstract" name="InvestmentsDisclosureAbstract" type="xbrli:stringItemType" 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_NonCurrentLiabilitiesLesseeAbstract" name="NonCurrentLiabilitiesLesseeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PrepaidExternalResearchAndDevelopmentCurrent" name="PrepaidExternalResearchAndDevelopmentCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_TwoThousandAndTwentyTermALoanAdvanceMember" name="TwoThousandAndTwentyTermALoanAdvanceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_LicenseAgreementWithBristolMayersEquibCompanyMember" name="LicenseAgreementWithBristolMayersEquibCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PreFundedWarrantsMember" name="PreFundedWarrantsMember" type="dtr-types:domainItemType" 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_LegacyQ32Member" name="LegacyQ32Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancingShares" name="IssuanceOfCommonStockAndPre-FundedWarrantsInFollow-OnFinancingShares" type="xbrli:sharesItemType" 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_PropertyAndEquipmentIncludeInAccountsPayable" name="PropertyAndEquipmentIncludeInAccountsPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_PayoffOfVentureDebt" name="PayoffOfVentureDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_PeriodOfObligationToPayRoyalties" name="PeriodOfObligationToPayRoyalties" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" 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_ResearchAndDevelopmentTaxIncentivePolicyTextBlock" name="ResearchAndDevelopmentTaxIncentivePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_IncreaseInCommonStockCapitalSharesReservedForFutureIssuance" name="IncreaseInCommonStockCapitalSharesReservedForFutureIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_AssetPurchaseAgreementMember" name="AssetPurchaseAgreementMember" type="dtr-types:domainItemType" 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_PersonnelRelatedCostsExcludingStockBasedCompensation" name="PersonnelRelatedCostsExcludingStockBasedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_HomologyMember" name="HomologyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ReservedForFutureIssuanceUnderTwoThousandAndSeventeenStockPlanMember" name="ReservedForFutureIssuanceUnderTwoThousandAndSeventeenStockPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TrancheThreeMilestoneMember" name="TrancheThreeMilestoneMember" 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_LossOnImpairmentOfEquityInvestment" name="LossOnImpairmentOfEquityInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_NatureOfBusinessTable" name="NatureOfBusinessTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AssetsNotYetInUseMember" name="AssetsNotYetInUseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PreFundedWarrantsAbstract" name="PreFundedWarrantsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_HorizonCollaborationAgreementMember" name="HorizonCollaborationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ShortTermInvestmentsAcquiredInReverseRecapitalization" name="ShortTermInvestmentsAcquiredInReverseRecapitalization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_LesseeOperatingLeaseNotYetCommencedIncreaseInPercentageOfBaseRent" name="LesseeOperatingLeaseNotYetCommencedIncreaseInPercentageOfBaseRent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_LoanAndSecuritySecondAmendmentAgreementWithSiliconValleyBankMember" name="LoanAndSecuritySecondAmendmentAgreementWithSiliconValleyBankMember" 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_ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourStockPlanMember" name="ReservedForFutureIssuanceUnderTwoThousandAndTwentyFourStockPlanMember" 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_ChangeInFairValueOfEquityInvestment" name="ChangeInFairValueOfEquityInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_ConvertiblePreferredStockPolicyTextBlock" name="ConvertiblePreferredStockPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_PreFundedWarrantTable" name="PreFundedWarrantTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" 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_Rule10B51ArrModifiedFlag" name="Rule10B51ArrModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_AccruedResearchAndDevelopmentExpensesCurrent" name="AccruedResearchAndDevelopmentExpensesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="qttb_OfferingPrice" name="OfferingPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_OperatingLeaseAssetsLesseeAbstract" name="OperatingLeaseAssetsLesseeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_TransactionCostsRelatedToReverseRecapitalization" name="TransactionCostsRelatedToReverseRecapitalization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceLineItems" name="DisclosureInTabularFormOfCommonStockSharesReservedForFutureIssuanceLineItems" 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_IssuanceOfCommonStockAndPre-FundedWarrantsInPrivatePlacementNetOfIssuanceCosts" name="IssuanceOfCommonStockAndPre-FundedWarrantsInPrivatePlacementNetOfIssuanceCosts" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_MilestonesPaymentReceivable" name="MilestonesPaymentReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_NatureOfBusinessLineItems" name="NatureOfBusinessLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_IssuanceOfCommonStockPursuantToAt-The-MarketOfferingNetOfDiscountsAndIssuanceCost" name="IssuanceOfCommonStockPursuantToAt-The-MarketOfferingNetOfDiscountsAndIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_CommitmentAndContingenciesLineItems" name="CommitmentAndContingenciesLineItems" type="xbrli:stringItemType" 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_DisclosureInTabularFormOfVentureDebtTable" name="DisclosureInTabularFormOfVentureDebtTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" 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_LoanAndSecurityAgreementWithSiliconValleyBankMember" name="LoanAndSecurityAgreementWithSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_AccountingPoliciesTable" name="AccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_PropertyAndEquipmentAdditionsIncludedInAccruedExpensesAndOtherLiabilities" name="PropertyAndEquipmentAdditionsIncludedInAccruedExpensesAndOtherLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_ConvertibleNotesPolicyTextBlock" name="ConvertibleNotesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_AmountOfRefundLiability" name="AmountOfRefundLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_TrancheTwoMilestoneMember" name="TrancheTwoMilestoneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_RoyaltyAsAPercentageOfNetSales" name="RoyaltyAsAPercentageOfNetSales" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_StockIssuedDuringPeriodValueToHomologyShareholdersInReverseRecapitalization" name="StockIssuedDuringPeriodValueToHomologyShareholdersInReverseRecapitalization" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="qttb_TwoThousandTwentyFourStockOptionAndIncentivePlanMember" name="TwoThousandTwentyFourStockOptionAndIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_SixthAmendmentAgreementWithSiliconValleyBankMember" name="SixthAmendmentAgreementWithSiliconValleyBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_SubleaseAggregateBaseRentObligation" name="SubleaseAggregateBaseRentObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="qttb_OxbSolutionsMember" name="OxbSolutionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_AccountingPoliciesLineItems" name="AccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="qttb_ComponentsOfInProcessResearchAndDevelopmentExpensesDomain" name="ComponentsOfInProcessResearchAndDevelopmentExpensesDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
</xsd:schema>
