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  <xs:element id="aqst_ConsiderationReceivableFromSaleOfFutureRevenuesInterests" abstract="false" name="ConsiderationReceivableFromSaleOfFutureRevenuesInterests" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_CollaborativeArrangementRevenueSharingPercentage" abstract="false" name="CollaborativeArrangementRevenueSharingPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="aqst_CollaborativeArrangementEstimatedRevenueSharePaymentsUponPurchasersReceiptYearTen" abstract="false" name="CollaborativeArrangementEstimatedRevenueSharePaymentsUponPurchasersReceiptYearTen" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_CollaborativeArrangementEstimatedRevenueSharePaymentsUponPurchasersReceiptThereafter" abstract="false" name="CollaborativeArrangementEstimatedRevenueSharePaymentsUponPurchasersReceiptThereafter" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_CapitalizedLegalFees" abstract="false" name="CapitalizedLegalFees" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_SaleOfStockSharesCommittedAggregateAmount" abstract="false" name="SaleOfStockSharesCommittedAggregateAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_SaleOfStockShareCommitmentPeriodFollowingEffectiveDate" abstract="false" name="SaleOfStockShareCommitmentPeriodFollowingEffectiveDate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aqst_LicenseAgreementTerm" abstract="false" name="LicenseAgreementTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aqst_AutomaticRenewalPeriodOfAgreement" abstract="false" name="AutomaticRenewalPeriodOfAgreement" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aqst_ProceedsFromSaleOfFutureRevenuesNet" abstract="false" name="ProceedsFromSaleOfFutureRevenuesNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_AdditionalProceedsFromSaleOfFutureRevenuesNet" abstract="false" name="AdditionalProceedsFromSaleOfFutureRevenuesNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_ContingentMonetizationAgreementMilestonePayment" abstract="false" name="ContingentMonetizationAgreementMilestonePayment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_SecuritiesPurchaseAgreementMember" abstract="true" name="SecuritiesPurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_ExistingWarrantsMember" abstract="true" name="ExistingWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_NewWarrantsMember" abstract="true" name="NewWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_CommonStockWarrantsMember" abstract="true" name="CommonStockWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_SharesOfCommonStockEntitledToPurchasersByPreFundedWarrants" abstract="false" name="SharesOfCommonStockEntitledToPurchasersByPreFundedWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="aqst_SharesOfCommonStockToBePurchasedByCommonStockWarrants" abstract="false" name="SharesOfCommonStockToBePurchasedByCommonStockWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="aqst_RoyaltyObligationPercentOfNetSales" abstract="false" name="RoyaltyObligationPercentOfNetSales" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="aqst_RoyaltyObligationTerm" abstract="false" name="RoyaltyObligationTerm" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aqst_InventoryPackingMaterialGross" abstract="false" name="InventoryPackingMaterialGross" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_ComputerNetworkEquipmentAndSoftwareMember" abstract="true" name="ComputerNetworkEquipmentAndSoftwareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_NumberOfOperatingLeases" abstract="false" name="NumberOfOperatingLeases" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aqst_LesseeOperatingLeaseLiabilityToBePaidYearFourAndThereafter" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidYearFourAndThereafter" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_CumulativeRoyaltyReceivable" abstract="false" name="CumulativeRoyaltyReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_NumberOfGuaranteedRoyaltyPayments" abstract="false" name="NumberOfGuaranteedRoyaltyPayments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aqst_MinimumAnnualRoyaltyReceivable" abstract="false" name="MinimumAnnualRoyaltyReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_NumberOfAnnualRoyaltyPaymentsReceivable" abstract="false" name="NumberOfAnnualRoyaltyPaymentsReceivable" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aqst_TwelvePointFiveSeniorSecuredNotesDueJune302025Member" abstract="true" name="TwelvePointFiveSeniorSecuredNotesDueJune302025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_RoyaltyObligationsMember" abstract="true" name="RoyaltyObligationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_ABLFacilityMember" abstract="true" name="ABLFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_TermLoanFacilityMember" abstract="true" name="TermLoanFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_RoyaltyRightAgreementsMember" abstract="true" name="RoyaltyRightAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_DebtCovenantRedemptionScenarioAxis" abstract="true" name="DebtCovenantRedemptionScenarioAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="aqst_DebtCovenantRedemptionScenarioDomain" abstract="true" name="DebtCovenantRedemptionScenarioDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_RedemptionScenario1Member" abstract="true" name="RedemptionScenario1Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_RedemptionScenario2Member" abstract="true" name="RedemptionScenario2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_DebtInstrumentExitFee" abstract="false" name="DebtInstrumentExitFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_DebtInstrumentRedemptionPriceBasisSpreadOnVariableRate" abstract="false" name="DebtInstrumentRedemptionPriceBasisSpreadOnVariableRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="aqst_LineOfCreditFacilityAccordionFeatureNetRevenueThreshold" abstract="false" name="LineOfCreditFacilityAccordionFeatureNetRevenueThreshold" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_LineOfCreditFacilityAccordionFeatureIncreaseLimit" abstract="false" name="LineOfCreditFacilityAccordionFeatureIncreaseLimit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_DebtInstrumentCovenantTieredRoyaltyPercentageTerm" abstract="false" name="DebtInstrumentCovenantTieredRoyaltyPercentageTerm" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aqst_RoyaltyObligationsGross" abstract="false" name="RoyaltyObligationsGross" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_MeasurementInputProbabilityOfSuccessMember" abstract="true" name="MeasurementInputProbabilityOfSuccessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_RoyaltyAgreementMeasurementInput" abstract="false" name="RoyaltyAgreementMeasurementInput" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="aqst_FirstAdditionalWarrantOfferingMember" abstract="true" name="FirstAdditionalWarrantOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_PreFundedWarrantsMember" abstract="true" name="PreFundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_A2020AdditionalNotesMember" abstract="true" name="A2020AdditionalNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_AdjustmentsToAdditionalPaidInCapitalFairValueOfWarrantsIssued" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalFairValueOfWarrantsIssued" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_ClassOfWarrantOrRightWarrantsExercised" abstract="false" name="ClassOfWarrantOrRightWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="aqst_ClassOfWarrantOrRightWarrantsIssuedDuringPeriod" abstract="false" name="ClassOfWarrantOrRightWarrantsIssuedDuringPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="aqst_SaleOfFutureRevenueRollForward" abstract="true" name="SaleOfFutureRevenueRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aqst_LiabilitiesSaleOfFutureRoyalties" abstract="false" name="LiabilitiesSaleOfFutureRoyalties" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_LiabilitiesSaleOfFutureRoyaltiesCurrent" abstract="false" name="LiabilitiesSaleOfFutureRoyaltiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_AssetRetirementObligationsDepreciationExpense" abstract="false" name="AssetRetirementObligationsDepreciationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_ManufacturingAndSupplyMember" abstract="true" name="ManufacturingAndSupplyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_ServiceBasedMember" abstract="true" name="ServiceBasedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_MarketBasedMember" abstract="true" name="MarketBasedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInShares" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInShares" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsEstimatedGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsEstimatedGrantDateFairValue" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="aqst_A2025MarketBasedMember" abstract="true" name="A2025MarketBasedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_A2022InducementEquityIncentivePlanMember" abstract="true" name="A2022InducementEquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_MarketConditionsAxis" abstract="true" name="MarketConditionsAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="aqst_MarketConditionsDomain" abstract="true" name="MarketConditionsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_MarketConditionRangeOneMember" abstract="true" name="MarketConditionRangeOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_MarketConditionRangeTwoMember" abstract="true" name="MarketConditionRangeTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_MarketConditionRangeThreeMember" abstract="true" name="MarketConditionRangeThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_MarketConditionRangeFourMember" abstract="true" name="MarketConditionRangeFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_MarketConditionRangeFiveMember" abstract="true" name="MarketConditionRangeFiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_MarketConditionRangeSixMember" abstract="true" name="MarketConditionRangeSixMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_VestingConditionAxis" abstract="true" name="VestingConditionAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="aqst_VestingConditionDomain" abstract="true" name="VestingConditionDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_VestingConditionRangeSevenMember" abstract="true" name="VestingConditionRangeSevenMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_VestingConditionRangeEightMember" abstract="true" name="VestingConditionRangeEightMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_VestingConditionRangeNineMember" abstract="true" name="VestingConditionRangeNineMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_VestingConditionRangeTenMember" abstract="true" name="VestingConditionRangeTenMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_VestingConditionRangeElevenMember" abstract="true" name="VestingConditionRangeElevenMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_VestingConditionRangeTwelveMember" abstract="true" name="VestingConditionRangeTwelveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAverageClosingPricesPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAverageClosingPricesPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentMarketConditionPerformancePriceThresholdPerShare" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentMarketConditionPerformancePriceThresholdPerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfPricingPeriods" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfPricingPeriods" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsDaysUtilizedInPricingPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsDaysUtilizedInPricingPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedForfeituresAndExpirationsInPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedForfeituresAndExpirationsInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="aqst_SuboxoneProduceLiabilityLitigationMember" abstract="true" name="SuboxoneProduceLiabilityLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_DebtInstrumentMilestoneTranchesAxis" abstract="true" name="DebtInstrumentMilestoneTranchesAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="aqst_DebtInstrumentMilestoneTranchesDomain" abstract="true" name="DebtInstrumentMilestoneTranchesDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_TrancheTwoMember" abstract="true" name="TrancheTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_TrancheThreeMember" abstract="true" name="TrancheThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_TrancheFourMember" abstract="true" name="TrancheFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_LesseeOperatingLeaseInitialRentAbatementPeriod" abstract="false" name="LesseeOperatingLeaseInitialRentAbatementPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aqst_LesseeOperatingLeaseNumberOfRenewalOptions" abstract="false" name="LesseeOperatingLeaseNumberOfRenewalOptions" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aqst_LineOfCreditFacilityAvailableBorrowingCapacityIncreaseLimit" abstract="false" name="LineOfCreditFacilityAvailableBorrowingCapacityIncreaseLimit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
