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  <element name="InitialTermOfAgreement" id="alxo_InitialTermOfAgreement" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InitialTermOfAgreementWithRelatedParty" id="alxo_InitialTermOfAgreementWithRelatedParty" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LabEquipmentAndOtherAssetsMember" id="alxo_LabEquipmentAndOtherAssetsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LesseeOperatingLeaseCommencingEndDate" id="alxo_LesseeOperatingLeaseCommencingEndDate" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LesseeOperatingLeaseLiabilityToBePaidYearFourAndFive" id="alxo_LesseeOperatingLeaseLiabilityToBePaidYearFourAndFive" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LesseeOperatingLeaseLiabilityToBePaidYearTwoAndThree" id="alxo_LesseeOperatingLeaseLiabilityToBePaidYearTwoAndThree" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LoanAgreementMember" id="alxo_LoanAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtMaturitiesRepaymentsOfDebtIncludingInterestAndPrincipal" id="alxo_LongTermDebtMaturitiesRepaymentsOfDebtIncludingInterestAndPrincipal" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtMaturitiesRepaymentsOfFinalPayment" id="alxo_LongTermDebtMaturitiesRepaymentsOfFinalPayment" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtMaturitiesRepaymentsOfInterest" id="alxo_LongTermDebtMaturitiesRepaymentsOfInterest" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MarketYieldAnalysisAndIncomeApproachMember" id="alxo_MarketYieldAnalysisAndIncomeApproachMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MasterServiceAgreementMember" id="alxo_MasterServiceAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MeasurementInputProbabilityOfOccurrenceMember" id="alxo_MeasurementInputProbabilityOfOccurrenceMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonCashAccumulatedDividendOnConvertiblePreferredStock" id="alxo_NonCashAccumulatedDividendOnConvertiblePreferredStock" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NoncashOrPartNoncashDebtIssuanceCostsInAccountsPayable" id="alxo_NoncashOrPartNoncashDebtIssuanceCostsInAccountsPayable" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NoncashOrPartNoncashFairValueOfCompoundDerivativeLiabilityAndWarrantLiabilityRelatedToTermLoan" id="alxo_NoncashOrPartNoncashFairValueOfCompoundDerivativeLiabilityAndWarrantLiabilityRelatedToTermLoan" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonrefundableLicenseRoyaltyAndPatentExpenses" id="alxo_NonrefundableLicenseRoyaltyAndPatentExpenses" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NotePurchaseAgreementMember" id="alxo_NotePurchaseAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NoticePeriodToRemedyBreachOfAgreement" id="alxo_NoticePeriodToRemedyBreachOfAgreement" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfCompanysInvestorsWhoAreInvestorsInRelatedPartyAsWell" id="alxo_NumberOfCompanysInvestorsWhoAreInvestorsInRelatedPartyAsWell" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfIndirectSubsidiaries" id="alxo_NumberOfIndirectSubsidiaries" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OfficeAndLaboratorySpaceMember" id="alxo_OfficeAndLaboratorySpaceMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OfficeSpaceMember" id="alxo_OfficeSpaceMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OperatingSubLeaseExpirationYear" id="alxo_OperatingSubLeaseExpirationYear" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OptionsIssuedAndOutstandingMember" id="alxo_OptionsIssuedAndOutstandingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OrganizationAndOfferingCostsPolicyTextBlock" id="alxo_OrganizationAndOfferingCostsPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OrganizationLineItems" id="alxo_OrganizationLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentForOfferingCost" id="alxo_PaymentForOfferingCost" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PotentiallyDilutiveSecuritiesOutstandingLineItems" id="alxo_PotentiallyDilutiveSecuritiesOutstandingLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PredecessorCompanyMember" id="alxo_PredecessorCompanyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PreferredSharesAuthorizedToBeIssuedUnderAgreement" id="alxo_PreferredSharesAuthorizedToBeIssuedUnderAgreement" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProceedsFromEquityFinancing" id="alxo_ProceedsFromEquityFinancing" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProceedsFromIssuanceOfRelatedPartiesConvertiblePreferredStock" id="alxo_ProceedsFromIssuanceOfRelatedPartiesConvertiblePreferredStock" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProformaAdjustmentToReflectAssumedConversionOfPreferredSharesAndAccruedDividendsAllocableToOrdinaryShareholders" id="alxo_ProformaAdjustmentToReflectAssumedConversionOfPreferredSharesAndAccruedDividendsAllocableToOrdinaryShareholders" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PropertyPlantAndEquipmentUsefulLifeTableTextBlock" id="alxo_PropertyPlantAndEquipmentUsefulLifeTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RecentlyIssuedAccountingPronouncementsPolicyPolicyTextBlock" id="alxo_RecentlyIssuedAccountingPronouncementsPolicyPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RelatedPartyAgreementAutomaticallyRenewalAdditionalTermUnlessTerminated" id="alxo_RelatedPartyAgreementAutomaticallyRenewalAdditionalTermUnlessTerminated" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RelatedPartyMarkupCostPercentage" id="alxo_RelatedPartyMarkupCostPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RelatedPartyMember" id="alxo_RelatedPartyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RenewalPeriodsOfAgreement" id="alxo_RenewalPeriodsOfAgreement" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ResearchAndDevelopmentServicesAgreementMember" id="alxo_ResearchAndDevelopmentServicesAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReverseStockSplitPolicyTextBlock" id="alxo_ReverseStockSplitPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock" id="alxo_ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfCommonStockReservedForFutureIssuanceTableTextBlock" id="alxo_ScheduleOfCommonStockReservedForFutureIssuanceTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfEarningsPerShareBasicAndDilutedProFormaTableTextBlock" id="alxo_ScheduleOfEarningsPerShareBasicAndDilutedProFormaTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfOrganizationTable" id="alxo_ScheduleOfOrganizationTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="SecondDrugProductManufacturerMember" id="alxo_SecondDrugProductManufacturerMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SecondTrancheMember" id="alxo_SecondTrancheMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SelexisSaMember" id="alxo_SelexisSaMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesAConvertiblePreferredStockMember" id="alxo_SeriesAConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesAPurchaseAgreementMember" id="alxo_SeriesAPurchaseAgreementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesbAndCconvertiblePreferredStockMember" id="alxo_SeriesbAndCconvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesBConvertiblePreferredStockMember" id="alxo_SeriesBConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeriesCConvertiblePreferredStockMember" id="alxo_SeriesCConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantAuthorized" id="alxo_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantAuthorized" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantCanceled" id="alxo_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantCanceled" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantGranted" id="alxo_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantGranted" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRepurchased" id="alxo_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRepurchased" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedExercised" id="alxo_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedExercised" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesLineItems" id="alxo_SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesTable" id="alxo_SignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="StanfordJuniorUniversityMember" id="alxo_StanfordJuniorUniversityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockholderApprovalMember" id="alxo_StockholderApprovalMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodSharesWarrantExercise" id="alxo_StockIssuedDuringPeriodSharesWarrantExercise" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodValueVestingOfEarlyExercisedStockOptions" id="alxo_StockIssuedDuringPeriodValueVestingOfEarlyExercisedStockOptions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockOptionsAuthorizedForFutureIssuanceMember" id="alxo_StockOptionsAuthorizedForFutureIssuanceMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockOptionsIssuedAndOutstandingMember" id="alxo_StockOptionsIssuedAndOutstandingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SubleaseAgreementTerminationMonthAndYear" id="alxo_SubleaseAgreementTerminationMonthAndYear" type="xbrli:gYearMonthItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SubsequentEventAbstract" id="alxo_SubsequentEventAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesLineItems" id="alxo_SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesTable" id="alxo_SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="TallacTherapeuticsMember" id="alxo_TallacTherapeuticsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TemporaryEquitySharesIssuedAndOutstanding" id="alxo_TemporaryEquitySharesIssuedAndOutstanding" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TemporaryEquityStockIssuedDuringPeriodShareNewIssues" id="alxo_TemporaryEquityStockIssuedDuringPeriodShareNewIssues" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TerminationOfAgreementWrittenNoticePeriod" id="alxo_TerminationOfAgreementWrittenNoticePeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TermLoanMember" id="alxo_TermLoanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TollnineMember" id="alxo_TollnineMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandFifteenEquityIncentivePlanMember" id="alxo_TwoThousandFifteenEquityIncentivePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandTwentyEquityIncentivePlanMember" id="alxo_TwoThousandTwentyEquityIncentivePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnauditedCondensedConsolidatedFinancialStatementsPolicyTextBlock" id="alxo_UnauditedCondensedConsolidatedFinancialStatementsPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UncategorizedAbstract" id="alxo_UncategorizedAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnderwritingCommissionsAndOfferingCostsPolicyTextBlock" id="alxo_UnderwritingCommissionsAndOfferingCostsPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UndesignatedPreferredStockMember" id="alxo_UndesignatedPreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnvestedEquitySharesOutstanding" id="alxo_UnvestedEquitySharesOutstanding" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="VestingOfEarlyExercisedStockOptions" id="alxo_VestingOfEarlyExercisedStockOptions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantLiabilityFairValueDisclosure" id="alxo_WarrantLiabilityFairValueDisclosure" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantLiabilityMember" id="alxo_WarrantLiabilityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantsAuthorizedForFutureIssuanceMember" id="alxo_WarrantsAuthorizedForFutureIssuanceMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantsIssuedAndOutstandingMember" id="alxo_WarrantsIssuedAndOutstandingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantsToPurchaseConvertiblePreferredStockMember" id="alxo_WarrantsToPurchaseConvertiblePreferredStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WeightedAverageBasicAndDilutedSharesOutstandingProForma" id="alxo_WeightedAverageBasicAndDilutedSharesOutstandingProForma" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
