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  <xsd:element id="alxo_OperatingLeaseExpirationYear" name="OperatingLeaseExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="alxo_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_OfficeAndLaboratorySpaceMember" name="OfficeAndLaboratorySpaceMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_MasterServiceAgreementMember" name="MasterServiceAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_SecondDrugProductManufacturerMember" name="SecondDrugProductManufacturerMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_InitialTermOfAgreement" name="InitialTermOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="alxo_RenewalPeriodsOfAgreement" name="RenewalPeriodsOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="alxo_LesseeOperatingLeaseCommencingEndDate" name="LesseeOperatingLeaseCommencingEndDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="alxo_OfficeSpaceMember" name="OfficeSpaceMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_PercentageOfFeeBasedRevenues" name="PercentageOfFeeBasedRevenues" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="alxo_ServicesAgreementsInitialTerm" name="ServicesAgreementsInitialTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="alxo_ServicesAgreementsInitialTermRenewedAdditionally" name="ServicesAgreementsInitialTermRenewedAdditionally" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="alxo_TallacServicesAgreementMember" name="TallacServicesAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_DrWanConsultingAgreementMember" name="DrWanConsultingAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_AssetTransferAgreementMember" name="AssetTransferAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_UndesignatedPreferredStockMember" name="UndesignatedPreferredStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="alxo_ConsultingAgreementsInitialTerm" name="ConsultingAgreementsInitialTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="alxo_ConsultingAgreementsInitialTermRenewedAdditionally" name="ConsultingAgreementsInitialTermRenewedAdditionally" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="alxo_PercentageOfTimePerformingActivities" name="PercentageOfTimePerformingActivities" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="alxo_CashInExchangeForTransferOfAssets" name="CashInExchangeForTransferOfAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="alxo_TemporaryEquityAccretionOfDividendsShares" name="TemporaryEquityAccretionOfDividendsShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
</xsd:schema>
