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  <xsd:element name="RoyaltyInterestFinancingAgreementMember" id="rytm_RoyaltyInterestFinancingAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ConvertiblePreferredStockDividends" id="rytm_ConvertiblePreferredStockDividends" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AcquiredInProcessResearchAndDevelopmentAssetsClassifiedAsOperatingActivities" id="rytm_AcquiredInProcessResearchAndDevelopmentAssetsClassifiedAsOperatingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NumberOfPharmaciesProductSold" id="rytm_NumberOfPharmaciesProductSold" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="OneHolderOfSeriesConvertiblePreferredStockMember" id="rytm_OneHolderOfSeriesConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SecondHolderOfSeriesConvertiblePreferredStockMember" id="rytm_SecondHolderOfSeriesConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PercentageOfOwnershipAfterConversion" id="rytm_PercentageOfOwnershipAfterConversion" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="TwoThousandSeventeenEmployeeAndEmploymentInducementPlan2022stockPurchasePlansInAggregateMember" id="rytm_TwoThousandSeventeenEmployeeAndEmploymentInducementPlan2022stockPurchasePlansInAggregateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
