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  <xs:element id="ngm_AmountOfFundReceivedForResearchActivitiesRequiredExpendableAmount" abstract="false" name="AmountOfFundReceivedForResearchActivitiesRequiredExpendableAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ngm_CollaborativeArrangementReviewTerm" abstract="false" name="CollaborativeArrangementReviewTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ngm_OfferingPeriodForPurchaseUnderEmployeeStockPurchasePlan" abstract="false" name="OfferingPeriodForPurchaseUnderEmployeeStockPurchasePlan" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ngm_MerckSharpAndDohmeCorporationMember" abstract="true" name="MerckSharpAndDohmeCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ngm_ClinicalDevelopmentEventAxis" abstract="true" name="ClinicalDevelopmentEventAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="ngm_AmountOfAdditionalFundReceivedForResearchActivities" abstract="false" name="AmountOfAdditionalFundReceivedForResearchActivities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ngm_StockIssuedDuringPeriodValueIssuanceOfUnderOpenMarketAgreement" abstract="false" name="StockIssuedDuringPeriodValueIssuanceOfUnderOpenMarketAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ngm_UpfrontLicenseFee" abstract="false" name="UpfrontLicenseFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ngm_AccruedClinicalTrialsAndResearchAndDevelopmentCostsCurrent" abstract="false" name="AccruedClinicalTrialsAndResearchAndDevelopmentCostsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ngm_SaleOfStockAggregateOfferingPrice" abstract="false" name="SaleOfStockAggregateOfferingPrice" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ngm_SecondIndicationMember" abstract="true" name="SecondIndicationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ngm_CommonStockOptionsAvailableForGrantMember" abstract="true" name="CommonStockOptionsAvailableForGrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ngm_CollaborativeArrangementAnnualFundingAmountOverAgreementTerm" abstract="false" name="CollaborativeArrangementAnnualFundingAmountOverAgreementTerm" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ngm_EligibleMilestonePaymentsReceivable" abstract="false" name="EligibleMilestonePaymentsReceivable" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ngm_TwoThousandNineteenEmployeeStockPurchasePlanMember" abstract="true" name="TwoThousandNineteenEmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
