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  <import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <import namespace="http://xbrl.sec.gov/dei/2020-01-31" schemaLocation="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <import namespace="http://fasb.org/us-roles/2020-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2020/elts/us-roles-2020-01-31.xsd" />
  <import namespace="http://fasb.org/us-gaap/2020-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd" />
  <import namespace="http://fasb.org/srt/2020-01-31" schemaLocation="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd" />
  <import namespace="http://xbrl.sec.gov/country/2020-01-31" schemaLocation="https://xbrl.sec.gov/country/2020/country-2020-01-31.xsd" />
  <element id="acur_CollaborationRevenueReceivable" name="CollaborationRevenueReceivable" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element name="RoyaltyReceivable" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" xbrli:balance="debit" substitutionGroup="xbrli:item" id="acur_RoyaltyReceivable" />
  <element id="acur_SalesReturnsLiabilityCurrent" name="SalesReturnsLiabilityCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="acur_ScheduleOfPropertyPlantAndEquipmentNetCarryingValueTableTextBlock" name="ScheduleOfPropertyPlantAndEquipmentNetCarryingValueTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element name="ScientificEquipmentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_ScientificEquipmentMember" />
  <element name="ComputerHardwareAndSoftwareMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_ComputerHardwareAndSoftwareMember" />
  <element name="LicenseDevelopmentAndCommercializationAgreementTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem" id="acur_LicenseDevelopmentAndCommercializationAgreementTable" />
  <element name="EgaletAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_EgaletAgreementMember" />
  <element id="acur_PaymentForTermination" name="PaymentForTermination" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_AccruedCostSharingExpenses" name="AccruedCostSharingExpenses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element name="OtherAccruedTaxesCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" xbrli:balance="credit" substitutionGroup="xbrli:item" id="acur_OtherAccruedTaxesCurrent" />
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentOtherThanOptionsDistributedInPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentOtherThanOptionsDistributedInPeriod" />
  <element name="EmployeeBenefitPlansDisclosureTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem" id="acur_EmployeeBenefitPlansDisclosureTable" />
  <element name="IncomeTaxDisclosureTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem" id="acur_IncomeTaxDisclosureTable" />
  <element id="acur_IncreaseDecreaseInCollaborationRevenueReceivable" name="IncreaseDecreaseInCollaborationRevenueReceivable" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element name="IncreaseDecreaseInRoyaltyReceivable" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" xbrli:balance="credit" substitutionGroup="xbrli:item" id="acur_IncreaseDecreaseInRoyaltyReceivable" />
  <element name="DescriptionOfOperationAndSummaryOfSignificantAccountingPoliciesDisclosureAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_DescriptionOfOperationAndSummaryOfSignificantAccountingPoliciesDisclosureAbstract" />
  <element id="acur_ProceedsFromMilestonePaymentOnAgreement" name="ProceedsFromMilestonePaymentOnAgreement" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="acur_WorkingCapital" name="WorkingCapital" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element name="KempharmAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_KempharmAgreementMember" />
  <element id="acur_AdditionalUpfrontPaymentReceivable" name="AdditionalUpfrontPaymentReceivable" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="acur_LicensingAgreementRoyaltyPercentage" name="LicensingAgreementRoyaltyPercentage" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_LicenseAgreementOptionProductsDescription" name="LicenseAgreementOptionProductsDescription" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element name="MainPointeAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_MainPointeAgreementMember" />
  <element name="LicenseDevelopmentAndCommercializationAgreementLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_LicenseDevelopmentAndCommercializationAgreementLineItems" />
  <element name="IncomeTaxDisclosureLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_IncomeTaxDisclosureLineItems" />
  <element id="acur_CommonStockIssuableAbstract" name="CommonStockIssuableAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_ClassOfWarrantOrRightTerm" name="ClassOfWarrantOrRightTerm" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element name="SaleOfStockIssuePriceDescription" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_SaleOfStockIssuePriceDescription" />
  <element name="ClassOfWarrantsOrRightsExpiryPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_ClassOfWarrantsOrRightsExpiryPeriod" />
  <element id="acur_NumberOfCommonStockNeedToHoldToDesignateAsDirector" name="NumberOfCommonStockNeedToHoldToDesignateAsDirector" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <element id="acur_IncreaseDecreaseInSalesReturnLiability" name="IncreaseDecreaseInSalesReturnLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element name="EmployeeBenefitPlansDisclosureLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_EmployeeBenefitPlansDisclosureLineItems" />
  <element name="SchutteNoteMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_SchutteNoteMember" />
  <element name="OperatingLossCarryforwardsExpirationTerm" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="acur_OperatingLossCarryforwardsExpirationTerm" />
  <element id="acur_OperatingLossCarryForwardsExpirationYear" name="OperatingLossCarryForwardsExpirationYear" nillable="true" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_FinancedInsurancePremiums" name="FinancedInsurancePremiums" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="acur_SchutteMember" name="SchutteMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_ContractBalanceAndPerformanceObligationsDescription" name="ContractBalanceAndPerformanceObligationsDescription" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_RevenueFromLicenseFee" name="RevenueFromLicenseFee" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_IncreaseDecreaseInInterestPayableToRelatedParty" name="IncreaseDecreaseInInterestPayableToRelatedParty" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="acur_ProceedsFromDistributionOfRestrictedStockUnits" name="ProceedsFromDistributionOfRestrictedStockUnits" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="acur_OtherSaleRevenuesNet" name="OtherSaleRevenuesNet" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_RevenueFromRoyalty" name="RevenueFromRoyalty" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_AbuseDeterrentPharmaMember" name="AbuseDeterrentPharmaMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_LicenseAndCollaborationAgreementsAbstract" name="LicenseAndCollaborationAgreementsAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_RsusMember" name="RsusMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_StockOptionPlanMember" name="StockOptionPlanMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_RestrictedStockAwardPlanMember" name="RestrictedStockAwardPlanMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_FourNonEmployeeDirectorsMember" name="FourNonEmployeeDirectorsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_SettledInCashMember" name="SettledInCashMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_VestedRestrictedStockUnitsMember" name="VestedRestrictedStockUnitsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_DistributedAndSettledInCommonStockMember" name="DistributedAndSettledInCommonStockMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_InterestPayableCurrentRelatedParty" name="InterestPayableCurrentRelatedParty" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="acur_AllocatedShareBasedCompensationExpenseAbstract" name="AllocatedShareBasedCompensationExpenseAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_AdPharmaAgreementMember" name="AdPharmaAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_MainpointePharmaceuticalsLlcMember" name="MainpointePharmaceuticalsLlcMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_WaiverOfExercisePriceIfExerciseOfOptionOccursByCertainDate" name="WaiverOfExercisePriceIfExerciseOfOptionOccursByCertainDate" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="acur_PeriodFromEffectiveDateForExerciseOfOption" name="PeriodFromEffectiveDateForExerciseOfOption" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_WeightedAverageNumberOfSharesWarrants" name="WeightedAverageNumberOfSharesWarrants" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_EmployeesMember" name="EmployeesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_SettlementForPurchasePriceMember" name="SettlementForPurchasePriceMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_IncomeLossFromOperation" name="IncomeLossFromOperation" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_FiniteLivedIntangibleAssetsExpectedAmortizationExpensePerQuarter" name="FiniteLivedIntangibleAssetsExpectedAmortizationExpensePerQuarter" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="acur_FiniteLivedIntangibleAssetsReserveForImpairment" name="FiniteLivedIntangibleAssetsReserveForImpairment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="acur_LicenseFeeReceivableFromRelatedPartiesCurrent" name="LicenseFeeReceivableFromRelatedPartiesCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="acur_IncreaseDecreaseInLicenseFeeReceivableFromRelatedParties" name="IncreaseDecreaseInLicenseFeeReceivableFromRelatedParties" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_RevenueFromProductSalesNetOfAllowance" name="RevenueFromProductSalesNetOfAllowance" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_LongTermDebtSecuredNoncurrent" name="LongTermDebtSecuredNoncurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="acur_PeriodToWaiveOptionProductExercisePrice" name="PeriodToWaiveOptionProductExercisePrice" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_ReimbursableResearchAndDevelopmentExpense" name="ReimbursableResearchAndDevelopmentExpense" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="acur_ShareBasedCompensationNonEmployeeServicesTransactionCashSettlementPercentage" name="ShareBasedCompensationNonEmployeeServicesTransactionCashSettlementPercentage" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_OptionProductExercisePriceWaivedIfExerciseOfOptionOccurredByFiveYears" name="OptionProductExercisePriceWaivedIfExerciseOfOptionOccurredByFiveYears" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="acur_MonthlyLicensePayments" name="MonthlyLicensePayments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="acur_FirstPaycheckProtectionProgramLoanMember" name="FirstPaycheckProtectionProgramLoanMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_SecondPaycheckProtectionProgramLoanMember" name="SecondPaycheckProtectionProgramLoanMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesDebtPrincipal" name="StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesDebtPrincipal" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesDebtPrincipal" name="StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesDebtPrincipal" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesDebtInterest" name="StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesDebtInterest" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesDebtInterest" name="StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesDebtInterest" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_DebtInstrumentLoanForgivenAmount" name="DebtInstrumentLoanForgivenAmount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="acur_DebtConversionOriginalDebtAmountAccruedInterest" name="DebtConversionOriginalDebtAmountAccruedInterest" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_RestrictedStockUnitAwardPlan2021Member" name="RestrictedStockUnitAwardPlan2021Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_AcuraPharmaceuticalsIncMember" name="AcuraPharmaceuticalsIncMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="acur_LeaseBalanceSheetDisclosureTableTextBlock" name="LeaseBalanceSheetDisclosureTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="acur_NetIncomeLosses" name="NetIncomeLosses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_NetIncomeLossBasic" name="NetIncomeLossBasic" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_NetIncomeLossDiluted" name="NetIncomeLossDiluted" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="acur_WeightedAverageNumberOfSharesRestrictedStockNonVestedDiluted" name="WeightedAverageNumberOfSharesRestrictedStockNonVestedDiluted" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
</schema>
