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  <xsd:element abstract="true" id="exel_FinancingLeaseLiabilitiesAbstract" name="FinancingLeaseLiabilitiesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_GlaxoSmithKlineMember" name="GlaxoSmithKlineMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_IncreaseDecreaseInAccruedClinicalLiabilities" name="IncreaseDecreaseInAccruedClinicalLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_IncreaseDecreaseInAccruedCollaborationLiability" name="IncreaseDecreaseInAccruedCollaborationLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_IncreaseDecreaseInCollaborativeArrangementMaximumAmountEligibleForDevelopmentAndRegulatoryMilestones" name="IncreaseDecreaseInCollaborativeArrangementMaximumAmountEligibleForDevelopmentAndRegulatoryMilestones" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_IncreaseDecreaseInLeaseLiabilityNoncurrent" name="IncreaseDecreaseInLeaseLiabilityNoncurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_IncreaseDecreaseInMaximumAmountEligibleForCommercialMilestonesUnderCollaborationsAgreement" name="IncreaseDecreaseInMaximumAmountEligibleForCommercialMilestonesUnderCollaborationsAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_IncreaseDecreaseInRebatesAndFeesPayable" name="IncreaseDecreaseInRebatesAndFeesPayable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_IpsenMember" name="IpsenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_LeaseArrangementsAxis" name="LeaseArrangementsAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_LeaseArrangementsDomain" name="LeaseArrangementsDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_LesseeOperatingAndFinancingLeaseLiabilitiesTableTextBlock" name="LesseeOperatingAndFinancingLeaseLiabilitiesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_LesseeOperatingLeaseLiabilityTenantImprovementReimbursements" name="LesseeOperatingLeaseLiabilityTenantImprovementReimbursements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="exel_LesseeOperatingLeaseNotYetCommencedMonthlyBasePayment" name="LesseeOperatingLeaseNotYetCommencedMonthlyBasePayment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_LesseeOperatingLeaseNotYetCommencedMonthlyBasePaymentAnnualIncreasePercentage" name="LesseeOperatingLeaseNotYetCommencedMonthlyBasePaymentAnnualIncreasePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_LesseeOperatingLeaseNumberOfRenewalOptions" name="LesseeOperatingLeaseNumberOfRenewalOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_LesseeOperatingLeaseOptionToTerminateAfterPeriod" name="LesseeOperatingLeaseOptionToTerminateAfterPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_LesseeOperatingLeaseReductionOfPaymentsDueAbstract" name="LesseeOperatingLeaseReductionOfPaymentsDueAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_LiabilitiesExpendituresIncurredButNotYetPaidToRelatedPartyTransactions" name="LiabilitiesExpendituresIncurredButNotYetPaidToRelatedPartyTransactions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_NotProbableMember" name="NotProbableMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_NumberofProductsinCommercialMarket" name="NumberofProductsinCommercialMarket" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_OperatingAndFinanceLeasesLiabilityLongTerm" name="OperatingAndFinanceLeasesLiabilityLongTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="exel_OperatingAndFinanceLeasesLiabilityTotal" name="OperatingAndFinanceLeasesLiabilityTotal" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="exel_OperatingLeaseAdditionalAreaOfRealEstateProperty" name="OperatingLeaseAdditionalAreaOfRealEstateProperty" nillable="true" substitutionGroup="xbrli:item" type="num:areaItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_OperatingLeaseLiabilitiesAbstract" name="OperatingLeaseLiabilitiesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OperatingLeaseLiabilitiesDurationOfMaturityAbstract" name="OperatingLeaseLiabilitiesDurationOfMaturityAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_OperatingLeaseSurrenderedAreaOfRealEstateProperty" name="OperatingLeaseSurrenderedAreaOfRealEstateProperty" nillable="true" substitutionGroup="xbrli:item" type="num:areaItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_OrganizationAndSummaryOfSignificantPoliciesLineItems" name="OrganizationAndSummaryOfSignificantPoliciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OrganizationAndSummaryOfSignificantPoliciesTable" name="OrganizationAndSummaryOfSignificantPoliciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OtherCollaborationMember" name="OtherCollaborationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OtherCustomersMember" name="OtherCustomersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_OtherLongtermAssetsMember" name="OtherLongtermAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_OwnershipInterestByMinorityShareholder" name="OwnershipInterestByMinorityShareholder" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_PerformanceSharesAchievedBeforeDecember312020Member" name="PerformanceSharesAchievedBeforeDecember312020Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_PerformanceSharesSecondProductApprovalMember" name="PerformanceSharesSecondProductApprovalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ProbableMember" name="ProbableMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ProductGrossMember" name="ProductGrossMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ProductsDerivedFromCabozantinibMember" name="ProductsDerivedFromCabozantinibMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ReconciliationOfSalesDiscountAndAllowancesReserveBalancesTableTextBlock" name="ReconciliationOfSalesDiscountAndAllowancesReserveBalancesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_RelatedPartyTransactionsAdvisoryFeesIncurred" name="RelatedPartyTransactionsAdvisoryFeesIncurred" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_RelatedPartyTransactionsCashAndInvestmentsManagedByMinorityOwner" name="RelatedPartyTransactionsCashAndInvestmentsManagedByMinorityOwner" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="exel_RelatedPartyTransactionsCashAndInvestmentsManagedByMinorityOwnerInvestedInMoneyMarketFund" name="RelatedPartyTransactionsCashAndInvestmentsManagedByMinorityOwnerInvestedInMoneyMarketFund" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="exel_ResearchandDevelopmentMember" name="ResearchandDevelopmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ResultingFromDiscoveryEffortsMember" name="ResultingFromDiscoveryEffortsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_RightOfUseAssetAmortization" name="RightOfUseAssetAmortization" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="exel_RightOfUseAssetObtainedInExchangeForLeaseLiability" name="RightOfUseAssetObtainedInExchangeForLeaseLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_SalesDiscountsAndAllowancesMember" name="SalesDiscountsAndAllowancesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndReleased" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndReleased" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndReleasedInPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndReleasedInPeriodWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageContractualTermAbstract" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageContractualTermAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherthanOptionsMaximumNumberOfSharesToVest" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherthanOptionsMaximumNumberOfSharesToVest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsMaximumPotentialToVest" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsMaximumPotentialToVest" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermAbstract" name="SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_StatusAxis" name="StatusAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_StatusDomain" name="StatusDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="exel_TenantLeaseImprovementsAllowance" name="TenantLeaseImprovementsAllowance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="exel_ValuationAllowancesAndReservesAdditionsForSalesInCurrentPeriod" name="ValuationAllowancesAndReservesAdditionsForSalesInCurrentPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="exel_ValuationAllowancesAndReservesAdditionsForSalesInPriorPeriod" name="ValuationAllowancesAndReservesAdditionsForSalesInPriorPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="exel_ValuationAllowancesAndReservesAdditionsToProvisionAbstract" name="ValuationAllowancesAndReservesAdditionsToProvisionAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
</xsd:schema>
</XBRL>
