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  <element id="arwr_AmountPaidOrAccruedForLeaseholdImprovementsNetOfTenantImprovementAllowances" name="AmountPaidOrAccruedForLeaseholdImprovementsNetOfTenantImprovementAllowances" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="arwr_PrimaryTenantImprovementAllowance" name="PrimaryTenantImprovementAllowance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="arwr_SecondaryTenantImprovementAllowance" name="SecondaryTenantImprovementAllowance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="arwr_OperatingLeaseNumberOfRenewalOptions" name="OperatingLeaseNumberOfRenewalOptions" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <element id="arwr_OtherRentalExpenses" name="OtherRentalExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_PaymentsUnderCapitalLease" name="PaymentsUnderCapitalLease" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_LeasedFacilityExpense" name="LeasedFacilityExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_FacilityRentExpense" name="FacilityRentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_NotesPayableAmortizedTerm" name="NotesPayableAmortizedTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_PromissoryNotePayableCommencementDate" name="PromissoryNotePayableCommencementDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_PromissoryNoteInterestRate" name="PromissoryNoteInterestRate" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_MilestonePayments" name="MilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="arwr_TwoThousandsFourEquityIncentivePlanMember" name="TwoThousandsFourEquityIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="arwr_TwoThousandsThirteenIncentivePlanMember" name="TwoThousandsThirteenIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="arwr_OutsideOfEquityCompensationPlansMember" name="OutsideOfEquityCompensationPlansMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="arwr_GrantDateFairValueOfOptionsGrantedDuringPeriod" name="GrantDateFairValueOfOptionsGrantedDuringPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_WarrantsIssuedToAcquireCommonStock" name="WarrantsIssuedToAcquireCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <element id="arwr_ClassOfWarrantOrRightCancelledUponExpiration" name="ClassOfWarrantOrRightCancelledUponExpiration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <element id="arwr_TwoThousandTenWarrantMember" name="TwoThousandTenWarrantMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="arwr_TwoThousandTwelveWarrantMember" name="TwoThousandTwelveWarrantMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="arwr_TwoThousandThirteenWarrantMember" name="TwoThousandThirteenWarrantMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="arwr_AblarisTherapeuticsMember" name="AblarisTherapeuticsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="arwr_TermOfExchangeRights" name="TermOfExchangeRights" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_ExchangeRightConvertibleConversionRatio" name="ExchangeRightConvertibleConversionRatio" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_NumberOfExchangeRightAreSold" name="NumberOfExchangeRightAreSold" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_BusinessCombinationPurchasePriceContingentConsiderationFairValue" name="BusinessCombinationPurchasePriceContingentConsiderationFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="arwr_BusinessCombinationContingentConsiderationPayments" name="BusinessCombinationContingentConsiderationPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="arwr_DeferredTaxAssetsInProcessResearchAndDevelopmentCost" name="DeferredTaxAssetsInProcessResearchAndDevelopmentCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_DeferredTaxAssetFairValueAdjustments" name="DeferredTaxAssetFairValueAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_DeferredTaxLiabilitiesStateTaxes" name="DeferredTaxLiabilitiesStateTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <element id="arwr_PercentageOfValuationAllowance" name="PercentageOfValuationAllowance" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <element id="arwr_FederalNetOperatingLossCarryForward" name="FederalNetOperatingLossCarryForward" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_FederalEstimatedNetOperatingLossCarryForward" name="FederalEstimatedNetOperatingLossCarryForward" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_StateNetOperatingLossCarryForwards" name="StateNetOperatingLossCarryForwards" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_StateEstimatedNetOperatingLossCarryForward" name="StateEstimatedNetOperatingLossCarryForward" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="arwr_EffectiveIncomeTaxRateReconciliationDeductionsStockCompensationPercent" name="EffectiveIncomeTaxRateReconciliationDeductionsStockCompensationPercent" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_EffectiveIncomeTaxRateReconciliationMarkToMarketAdjustments" name="EffectiveIncomeTaxRateReconciliationMarkToMarketAdjustments" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_EffectiveIncomeTaxRateReconciliationNondeductibleIncomeExpenseOther" name="EffectiveIncomeTaxRateReconciliationNondeductibleIncomeExpenseOther" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_EmployeeContributionsUpToThreePercentMember" name="EmployeeContributionsUpToThreePercentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="arwr_EmployeeContributionNextTwoPercentMember" name="EmployeeContributionNextTwoPercentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
</schema>
