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  <xs:element id="arwr_GSKHBVAgreementMember" abstract="true" name="GSKHBVAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="arwr_ClassOfWarrantOrRightPurchasePriceOfWarrantsOrRights" abstract="false" name="ClassOfWarrantOrRightPurchasePriceOfWarrantsOrRights" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
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  <xs:element id="arwr_MilestonePaymentDueFromCollaborativeAgreement" abstract="false" name="MilestonePaymentDueFromCollaborativeAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="arwr_CommitmentsCapitalExpendituresIncurredToDate" abstract="false" name="CommitmentsCapitalExpendituresIncurredToDate" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="arwr_ResearchFacilityInSanDiegoMember" abstract="true" name="ResearchFacilityInSanDiegoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_ResearchFacilityInMadisonMember" abstract="true" name="ResearchFacilityInMadisonMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_ColoradoOwnerLLCMember" abstract="true" name="ColoradoOwnerLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="arwr_ProceedsFromTenantImprovementAllowance" abstract="false" name="ProceedsFromTenantImprovementAllowance" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_CashFlowOperatingActivitiesLesseeCashReceivedForAmountsIncludedInMeasurementOfLeaseLiabilitiesAbstract" abstract="true" name="CashFlowOperatingActivitiesLesseeCashReceivedForAmountsIncludedInMeasurementOfLeaseLiabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
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  <xs:element id="arwr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsOutstanding" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsOutstanding" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
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  <xs:element id="arwr_EmployeeContributionNextTwoPercentMember" abstract="true" name="EmployeeContributionNextTwoPercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="arwr_UpfrontPaymentReceivedLiabilityRelatedToSaleOfFutureRoyalties" abstract="false" name="UpfrontPaymentReceivedLiabilityRelatedToSaleOfFutureRoyalties" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_MilestonePaymentReceivableUponAchievementOfEnrollmentInPhase3ClinicalTrial" abstract="false" name="MilestonePaymentReceivableUponAchievementOfEnrollmentInPhase3ClinicalTrial" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_MilestonePaymentReceivableUponFDAApproval" abstract="false" name="MilestonePaymentReceivableUponFDAApproval" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="arwr_LiabilitySaleOfFutureRoyaltiesRollForward" abstract="true" name="LiabilitySaleOfFutureRoyaltiesRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
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  <xs:element id="arwr_FinancingAgreementMOICPaymentMember" abstract="true" name="FinancingAgreementMOICPaymentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_DebtInstrumentCovenantMultipleOfInvestedCapital" abstract="false" name="DebtInstrumentCovenantMultipleOfInvestedCapital" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="arwr_DebtInstrumentPrepaymentPercentage" abstract="false" name="DebtInstrumentPrepaymentPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="arwr_DebtInstrumentMultipleOfInvestmentCapitalExpectedToBeAppliedToPrincipalUponRepayment" abstract="false" name="DebtInstrumentMultipleOfInvestmentCapitalExpectedToBeAppliedToPrincipalUponRepayment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_DebtInstrumentCovenantMinimumLiquidityIfCapitalizationIsAboveThreshold" abstract="false" name="DebtInstrumentCovenantMinimumLiquidityIfCapitalizationIsAboveThreshold" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_DebtInstrumentCovenantMarketCapitalizationThreshold" abstract="false" name="DebtInstrumentCovenantMarketCapitalizationThreshold" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_FinancingAgreementInitialTermLoanInterestMember" abstract="true" name="FinancingAgreementInitialTermLoanInterestMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_OperatingSegmentMember" abstract="true" name="OperatingSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_ResearchAndDevelopmentExpenseCandidateCosts" abstract="false" name="ResearchAndDevelopmentExpenseCandidateCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_ResearchAndDevelopmentExpenseDiscoveryCosts" abstract="false" name="ResearchAndDevelopmentExpenseDiscoveryCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_ResearchAndDevelopmentExpenseSalariesExpense" abstract="false" name="ResearchAndDevelopmentExpenseSalariesExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_ResearchAndDevelopmentExpenseFacilitiesRelatedExpense" abstract="false" name="ResearchAndDevelopmentExpenseFacilitiesRelatedExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_ResearchAndDevelopmentExpenseExcludingNoncashExpense" abstract="false" name="ResearchAndDevelopmentExpenseExcludingNoncashExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_GeneralAndAdministrativeExpenseFacilitiesRelatedExpense" abstract="false" name="GeneralAndAdministrativeExpenseFacilitiesRelatedExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_GeneralAndAdministrativeExpenseExcludingNoncashExpense" abstract="false" name="GeneralAndAdministrativeExpenseExcludingNoncashExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_NovartisCollaborationAgreementMember" abstract="true" name="NovartisCollaborationAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_PaymentReceivableInCollaborationArrangementsUponTargetNomination" abstract="false" name="PaymentReceivableInCollaborationArrangementsUponTargetNomination" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="arwr_AdeoyeOlukotunMember" abstract="true" name="AdeoyeOlukotunMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_ChristopherAnzaloneMember" abstract="true" name="ChristopherAnzaloneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_DanielApelMember" abstract="true" name="DanielApelMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_JamesHamiltonMember" abstract="true" name="JamesHamiltonMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_MauroFerrariMember" abstract="true" name="MauroFerrariMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_PatrickOBrienMember" abstract="true" name="PatrickOBrienMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_PatrickOBrienSharesVestingAndSubjectToSellToCoverMember" abstract="true" name="PatrickOBrienSharesVestingAndSubjectToSellToCoverMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_PatrickOBrienOtherSharesBeingSoldMember" abstract="true" name="PatrickOBrienOtherSharesBeingSoldMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_VictoriaVakienerMember" abstract="true" name="VictoriaVakienerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="arwr_WilliamWaddillMember" abstract="true" name="WilliamWaddillMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
