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  <element id="arwr_InvestmentInPreferredStockByOutsider" name="InvestmentInPreferredStockByOutsider" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
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  <element id="arwr_WarrantSevenMember" name="WarrantSevenMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
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  <element id="arwr_ExchangeRightConvertibleConversionRatioForFourYear" name="ExchangeRightConvertibleConversionRatioForFourYear" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="arwr_ExchangeRightConvertibleConversionRatioForFiveYear" name="ExchangeRightConvertibleConversionRatioForFiveYear" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
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</schema>
