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  <xs:element id="aqst_NewWarrants2.60ExercisePriceMember" abstract="true" name="NewWarrants2.60ExercisePriceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_AdditionalWarrantsMember" abstract="true" name="AdditionalWarrantsMember" 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_ClassOfWarrantOrRightExercises" abstract="false" name="ClassOfWarrantOrRightExercises" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <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_SeveranceCostLiability" abstract="false" name="SeveranceCostLiability" 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_A2022InducementEquityIncentivePlanMember" abstract="true" name="A2022InducementEquityIncentivePlanMember" 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_A2025MarketBasedMember" abstract="true" name="A2025MarketBasedMember" 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsGrantDateFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodIntrinsicValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfOfferingPeriods" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfOfferingPeriods" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <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_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aqst_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOrExpectedToVestAggregateIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOrExpectedToVestAggregateIntrinsicValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_BlackScholesMember" abstract="true" name="BlackScholesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aqst_TaxCutsAndJobsActOf2017DeferredTaxAssetsInterestLimitation" abstract="false" name="TaxCutsAndJobsActOf2017DeferredTaxAssetsInterestLimitation" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_DeferredTaxAssetsSaleOfFutureRevenue" abstract="false" name="DeferredTaxAssetsSaleOfFutureRevenue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_DeferredTaxAssetRoyaltyObligations" abstract="false" name="DeferredTaxAssetRoyaltyObligations" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_DeferredTaxAssetsOIDAndDeferredFinancingCost" abstract="false" name="DeferredTaxAssetsOIDAndDeferredFinancingCost" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_DeferredTaxLiabilitiesRightOfUseAssets" abstract="false" name="DeferredTaxLiabilitiesRightOfUseAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_IncomeTaxDisclosureTable" abstract="true" name="IncomeTaxDisclosureTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="aqst_IncomeTaxDisclosureLineItems" abstract="true" name="IncomeTaxDisclosureLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aqst_IncomeTaxExaminationEmployeeRetentionTaxCreditRefund" abstract="false" name="IncomeTaxExaminationEmployeeRetentionTaxCreditRefund" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aqst_EffectiveIncomeTaxRateReconciliationPermanentDifferencesPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationPermanentDifferencesPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="aqst_EffectiveIncomeTaxRateReconciliationProvisionToReturnAdjustmentsPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationProvisionToReturnAdjustmentsPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <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_CassieJungMember" abstract="true" name="CassieJungMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
