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  <xs:element id="exel_EligiblePaymentFromCollaborationForDevelopmentAndRegulatoryMilestoneAchievementUnderCollaborationsAgreement" abstract="false" name="EligiblePaymentFromCollaborationForDevelopmentAndRegulatoryMilestoneAchievementUnderCollaborationsAgreement" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="exel_RevenueFromContractWithCustomerRegulatoryMilestoneApplicationSubmission" abstract="false" name="RevenueFromContractWithCustomerRegulatoryMilestoneApplicationSubmission" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="exel_CollaborativeArrangementwithTakedaMember" abstract="true" name="CollaborativeArrangementwithTakedaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="exel_CollaborativeArrangementswithGlaxoSmithKlineMember" abstract="true" name="CollaborativeArrangementswithGlaxoSmithKlineMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="exel_CollaborativeArrangementsWithRoyaltyPharmaMember" abstract="true" name="CollaborativeArrangementsWithRoyaltyPharmaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exel_CollaborativeArrangementwithGenentechMember" abstract="true" name="CollaborativeArrangementwithGenentechMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="exel_ResearchCollaborationsInLicensingArrangementsAndOtherBusinessDevelopmentActivitiesMember" abstract="true" name="ResearchCollaborationsInLicensingArrangementsAndOtherBusinessDevelopmentActivitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="exel_CollaborativeArrangementRightsAndObligationsMaximumAggregateRegulatoryMilestonePayments" abstract="false" name="CollaborativeArrangementRightsAndObligationsMaximumAggregateRegulatoryMilestonePayments" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="exel_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAndAvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" abstract="false" name="CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAndAvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="exel_TSRBasedRestrictedStockUnitsMember" abstract="true" name="TSRBasedRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
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  <xs:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardReductionInShareReserveDueToOtherAwards" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardReductionInShareReserveDueToOtherAwards" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
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  <xs:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndReleased" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndReleased" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndReleasedInPeriodWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndReleasedInPeriodWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
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  <xs:element id="exel_EffectiveIncomeTaxRateReconciliationBrandedPrescriptionDrugFee" abstract="false" name="EffectiveIncomeTaxRateReconciliationBrandedPrescriptionDrugFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exel_EffectiveIncomeTaxRateReconciliationNondeductibleWarrantPurchase" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleWarrantPurchase" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="exel_DeferredTaxLiabilitiesLeaseRightOfUseAssets" abstract="false" name="DeferredTaxLiabilitiesLeaseRightOfUseAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="exel_HeadquartersLeaseMember" abstract="true" name="HeadquartersLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="exel_MSNIIANDAMember" abstract="true" name="MSNIIANDAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exel_A2024RestructuringPlanMember" abstract="true" name="A2024RestructuringPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="exel_LossContingencyNumberOfLawsuitsConsolidated" abstract="false" name="LossContingencyNumberOfLawsuitsConsolidated" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="exel_OperatingLeaseAssetsAbstract" abstract="true" name="OperatingLeaseAssetsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="exel_OperatingLeaseLiabilitiesAbstract" abstract="true" name="OperatingLeaseLiabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="exel_LesseeOperatingLeaseReductionOfPaymentsDueAbstract" abstract="true" name="LesseeOperatingLeaseReductionOfPaymentsDueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="exel_LeaseTerminationMember" abstract="true" name="LeaseTerminationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exel_ImpairmentOfLongLivedAssetsMember" abstract="true" name="ImpairmentOfLongLivedAssetsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exel_RestructuringChargesInitialCosts" abstract="false" name="RestructuringChargesInitialCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exel_JackLWyszomierskiMember" abstract="true" name="JackLWyszomierskiMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exel_SGailEckhardtMember" abstract="true" name="SGailEckhardtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
