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  <xsd:element id="eras_NoncashPreferredStockPurchaseRightLiability" name="NoncashPreferredStockPurchaseRightLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_NoticePeriodForCancellationOfLease" name="NoticePeriodForCancellationOfLease" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_OneTimeLicensePayment" name="OneTimeLicensePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_OperatingLeaseCancellationPayment" name="OperatingLeaseCancellationPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_OperatingLeasesCancelableAndNonCancellableExpirationDates" name="OperatingLeasesCancelableAndNonCancellableExpirationDates" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_OperatingLeasesNonCancelableExpirationDates" name="OperatingLeasesNonCancelableExpirationDates" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_OperatingLossCarryforwardsExpirationYear" name="OperatingLossCarryforwardsExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_OwnershipPercentageOfEquityOrAssets" name="OwnershipPercentageOfEquityOrAssets" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="eras_PaymentRelatedToPublicationOfUSPatentApplication" name="PaymentRelatedToPublicationOfUSPatentApplication" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_PercentageOfObligationToPayThirdTierSublicensingFees" name="PercentageOfObligationToPayThirdTierSublicensingFees" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_PreferredStockPurchaseRightLiability" name="PreferredStockPurchaseRightLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_ProceedsFromIssuanceOfCommonStockUnderTheEmployeeStockPurchasePlan" name="ProceedsFromIssuanceOfCommonStockUnderTheEmployeeStockPurchasePlan" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_ProceedsFromTheDisgorgementOfStockholdersShortSwingProfits" name="ProceedsFromTheDisgorgementOfStockholdersShortSwingProfits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_PurchaseAgreementTerminationDate" name="PurchaseAgreementTerminationDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_ReductionInOperatingLeaseAssetsDueToLeaseAmendment" name="ReductionInOperatingLeaseAssetsDueToLeaseAmendment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_ReimbursementOfCertainInitialManufacturingCosts" name="ReimbursementOfCertainInitialManufacturingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_RepurchasesOfEarlyExercisedStockOptionsAndRestrictedStock" name="RepurchasesOfEarlyExercisedStockOptionsAndRestrictedStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_SalesMilestonePaymentsObligation" name="SalesMilestonePaymentsObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_ShareBasedCompensationArrangementByShareBasedPaymentAwardCommonStockSharesSubjectToForfeiture" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardCommonStockSharesSubjectToForfeiture" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="eras_ShareBasedCompensationArrangementByShareBasedPaymentAwardOfferingPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOfferingPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesSubjectToRepurchase" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesSubjectToRepurchase" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="eras_ShareBasedCompensationByShareBasedPaymentAwardOptionsGrantedInPeriodTerm" name="ShareBasedCompensationByShareBasedPaymentAwardOptionsGrantedInPeriodTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_ShareBasedPaymentArrangementWithheldOnBehalfOfEmployeesForFuturePurchase" name="ShareBasedPaymentArrangementWithheldOnBehalfOfEmployeesForFuturePurchase" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_SharesOfCommonStockSubjectToRepurchase" name="SharesOfCommonStockSubjectToRepurchase" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="eras_StockHoldingPeriodForOwnershipChange" name="StockHoldingPeriodForOwnershipChange" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_StockIssuedDuringPeriodInConnectionWithLicensingAgreementShares" name="StockIssuedDuringPeriodInConnectionWithLicensingAgreementShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_StockIssuedDuringPeriodInConnectionWithLicensingAgreementValue" name="StockIssuedDuringPeriodInConnectionWithLicensingAgreementValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_StockIssuedDuringPeriodValueVestingOfEarlyExercisedStockOptions" name="StockIssuedDuringPeriodValueVestingOfEarlyExercisedStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_TaxCreditCarryforwardExpirationYear" name="TaxCreditCarryforwardExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_TaxCutsAndJobsActOf2017NetOperatingLossCarryoversOffsetPercentage" name="TaxCutsAndJobsActOf2017NetOperatingLossCarryoversOffsetPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_TemporaryEquityAdditionalSharesIssued" name="TemporaryEquityAdditionalSharesIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_TemporaryEquityStockIssuanceCosts" name="TemporaryEquityStockIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_TemporaryEquityStockIssuedDuringPeriodSharesAcquisition" name="TemporaryEquityStockIssuedDuringPeriodSharesAcquisition" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_TemporaryEquityStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" name="TemporaryEquityStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_TemporaryEquityStockIssuedDuringPeriodSharesInConnectionWithAssetAcquisition" name="TemporaryEquityStockIssuedDuringPeriodSharesInConnectionWithAssetAcquisition" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_TemporaryEquityStockIssuedDuringPeriodValueAcquisition" name="TemporaryEquityStockIssuedDuringPeriodValueAcquisition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_TemporaryEquityStockIssuedDuringPeriodValueConversionOfConvertibleSecurities" name="TemporaryEquityStockIssuedDuringPeriodValueConversionOfConvertibleSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_TenantImprovementAllowance" name="TenantImprovementAllowance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_TenantImprovementAllowanceIncludedInOperatingLeaseLiabilities" name="TenantImprovementAllowanceIncludedInOperatingLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_TermForCancellationOfLease" name="TermForCancellationOfLease" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_UnderwritingDiscountsAndCommissions" name="UnderwritingDiscountsAndCommissions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_UnrecognizedTaxBenefitsIncreasesDecreaseResultingFromPriorPeriodTaxPositions" name="UnrecognizedTaxBenefitsIncreasesDecreaseResultingFromPriorPeriodTaxPositions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_UnvestedEarlyExercisedStockOptionLiability" name="UnvestedEarlyExercisedStockOptionLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_UpfrontPayment" name="UpfrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_UpfrontPaymentMade" name="UpfrontPaymentMade" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="eras_VestingOfEarlyExercisedOptions" name="VestingOfEarlyExercisedOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="eras_AssetAcquisitionsLineItems" name="AssetAcquisitionsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_IncomeTaxesLineItems" name="IncomeTaxesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_LicenseAgreementsLineItems" name="LicenseAgreementsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_OrganizationAndBasisOfPresentationLineItems" name="OrganizationAndBasisOfPresentationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SummaryOfSignificantAccountingPoliciesLineItems" name="SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_AffiniTTherapeuticsIncMember" name="AffiniTTherapeuticsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_AsanaMergerAgreementMember" name="AsanaMergerAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_AtTimeOptionIsGrantedMember" name="AtTimeOptionIsGrantedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_AwardsAvailableForFutureGrantMember" name="AwardsAvailableForFutureGrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_ConversionOfB2PreferredStockInFutureIssuanceMember" name="ConversionOfB2PreferredStockInFutureIssuanceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_EmergeLifeSciencesPurchaseAgreementMember" name="EmergeLifeSciencesPurchaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_ErascaFoundationMember" name="ErascaFoundationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_EstimatedSharesPurchasableUnderTheEmployeeStockPurchasePlanMember" name="EstimatedSharesPurchasableUnderTheEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_FirstAmendmentToTwoThousandAndTwentyLeaseMember" name="FirstAmendmentToTwoThousandAndTwentyLeaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_FirstLicensedProductMember" name="FirstLicensedProductMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_ForHoldersOfMoreThanTenPercentOfCombinedVotingPowerOfAllClassesOfStockMember" name="ForHoldersOfMoreThanTenPercentOfCombinedVotingPowerOfAllClassesOfStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_KatmaiPharmaceuticalsIncorporationMember" name="KatmaiPharmaceuticalsIncorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_LicenseAgreementMember" name="LicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_LifeArcMember" name="LifeArcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_LongTermInvestmentsMember" name="LongTermInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_MeasurementInputFairValueOfUnderlyingPreferredStockMember" name="MeasurementInputFairValueOfUnderlyingPreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_NiKangTherapeuticsIncorporationMember" name="NiKangTherapeuticsIncorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_OptionsEarlyExercisedSubjectToFutureVestingMember" name="OptionsEarlyExercisedSubjectToFutureVestingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_OtherStateMember" name="OtherStateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_PerformanceBasedOptionsMember" name="PerformanceBasedOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_PreferredStockPurchaseRightLiabilityMember" name="PreferredStockPurchaseRightLiabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_RestrictedStockSubjectToFutureVestingMember" name="RestrictedStockSubjectToFutureVestingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SecondLicensedProductMember" name="SecondLicensedProductMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SeriesAConvertiblePreferredStockMember" name="SeriesAConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SeriesB1ConvertiblePreferredStockAndSeriesB2ConvertiblePreferredStockMember" name="SeriesB1ConvertiblePreferredStockAndSeriesB2ConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SeriesB1ConvertiblePreferredStockMember" name="SeriesB1ConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SeriesB2ConvertiblePreferredStockMember" name="SeriesB2ConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SeriesBConvertiblePreferredStockPurchaseAgreementMember" name="SeriesBConvertiblePreferredStockPurchaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SharesAvailableForPurchaseUnderEmployeeStockPurchasePlanMember" name="SharesAvailableForPurchaseUnderEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SupranationalDebtSecuritiesMember" name="SupranationalDebtSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_TheRegentsOfUniversityOfCaliforniaMember" name="TheRegentsOfUniversityOfCaliforniaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_TwoThousandEighteenEquityIncentivePlanMember" name="TwoThousandEighteenEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_TwoThousandEighteenLeaseMember" name="TwoThousandEighteenLeaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_TwoThousandTwentyLeaseMember" name="TwoThousandTwentyLeaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_TwoThousandTwentyOneIncentiveAwardPlanMember" name="TwoThousandTwentyOneIncentiveAwardPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_TwoThousandTwentyOneLeaseMember" name="TwoThousandTwentyOneLeaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_AssetAcquisitionsTable" name="AssetAcquisitionsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_IncomeTaxesTable" name="IncomeTaxesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_LicenseAgreementsTable" name="LicenseAgreementsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_OrganizationAndBasisOfPresentationTable" name="OrganizationAndBasisOfPresentationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="eras_AssetAcquisitionsTextBlock" name="AssetAcquisitionsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_CommonStockReservedForFutureIssuanceTableTextBlock" name="CommonStockReservedForFutureIssuanceTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_COVID19PandemicTextBlock" name="COVID19PandemicTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_DeferredOfferingCostsPolicyTextBlock" name="DeferredOfferingCostsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_LicenseAgreementsDisclosureTextBlock" name="LicenseAgreementsDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_PreferredStockPurchaseRightLiabilitiesPolicyTextBlock" name="PreferredStockPurchaseRightLiabilitiesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="eras_UnauditedInterimFinancialInformationPolicyTextBlock" name="UnauditedInterimFinancialInformationPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
