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  <xsd:element name="DavidMcgirrMember" id="rytm_DavidMcgirrMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
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  <xsd:element name="ChristopherGermanMember" id="rytm_ChristopherGermanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DebtSecuritiesAvailableForSaleCreditLossExpenseReversal" id="rytm_DebtSecuritiesAvailableForSaleCreditLossExpenseReversal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RepaymentOfUpfrontFeesOnTermination" id="rytm_RepaymentOfUpfrontFeesOnTermination" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
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  <xsd:element name="AdditionalConsiderationForShareRepurchase" id="rytm_AdditionalConsiderationForShareRepurchase" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ReversalOfLicenseRevenueRecognizedOnTerminationOfContract" id="rytm_ReversalOfLicenseRevenueRecognizedOnTerminationOfContract" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NetReductionInLicenseRevenueUponTerminationOfContract" id="rytm_NetReductionInLicenseRevenueUponTerminationOfContract" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
</xsd:schema>
