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<!-- Creation Date :2023-05-11T12:32:56.7401+00:00 -->
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  <xsd:element id="hrtx_AvailableForSaleSecuritiesDebtSecuritiesCurrentContractualMaturitiesOfThreeMonthsToOneYear" name="AvailableForSaleSecuritiesDebtSecuritiesCurrentContractualMaturitiesOfThreeMonthsToOneYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="hrtx_CommonSharesRegisteredForResaleInConnectionWithConvertibleNotes" name="CommonSharesRegisteredForResaleInConnectionWithConvertibleNotes" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
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  <xsd:element id="hrtx_ZYNRELEFsMember" name="ZYNRELEFsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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</xsd:schema>
