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<import namespace="http://fasb.org/srt/2018-01-31" schemaLocation="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd" />
<element name="DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_DocumentAndEntityInformationAbstract" substitutionGroup="xbrli:item" />
<element name="IncreaseDecreaseInDeferredRentNoncurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_IncreaseDecreaseInDeferredRentNoncurrent" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="AccretionAndAmortizationOfInvestmentsInMarketableSecurities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_AccretionAndAmortizationOfInvestmentsInMarketableSecurities" substitutionGroup="xbrli:item" xbrli:balance="credit" />
<element name="NoncashRentExpense" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_NoncashRentExpense" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="CollaborationAgreementAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_CollaborationAgreementAbstract" substitutionGroup="xbrli:item" />
<element name="CollaborativeAndLicenseArrangementDisclosureTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_CollaborativeAndLicenseArrangementDisclosureTextBlock" substitutionGroup="xbrli:item" />
<element name="MilestonesAndResearchAgreementsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_MilestonesAndResearchAgreementsAbstract" substitutionGroup="xbrli:item" />
<element name="MilestonesAndResearchAgreementsTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_MilestonesAndResearchAgreementsTextBlock" substitutionGroup="xbrli:item" />
<element name="StockbasedCompensationPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_StockbasedCompensationPolicyTextBlock" substitutionGroup="xbrli:item" />
<element name="SignificantAccountingPoliciesPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_SignificantAccountingPoliciesPolicyTextBlock" substitutionGroup="xbrli:item" />
<element name="ScheduleOfCollaborationRevenueRecognizedWithThePeriod" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_ScheduleOfCollaborationRevenueRecognizedWithThePeriod" substitutionGroup="xbrli:item" />
<element name="DisclosureOfQuantitativeInformationOfOperatingLeasesTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_DisclosureOfQuantitativeInformationOfOperatingLeasesTableTextBlock" substitutionGroup="xbrli:item" />
<element name="WarrantsToPurchaseCommonStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_WarrantsToPurchaseCommonStockMember" substitutionGroup="xbrli:item" />
<element name="OptionsToPurchaseCommonStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_OptionsToPurchaseCommonStockMember" substitutionGroup="xbrli:item" />
<element name="RestrictedStockUnitsToPurchaseCommonStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_RestrictedStockUnitsToPurchaseCommonStockMember" substitutionGroup="xbrli:item" />
<element name="UsForeignCommercialPaperMemberMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_UsForeignCommercialPaperMemberMember" substitutionGroup="xbrli:item" />
<element name="AccruedExpensesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_AccruedExpensesTable" substitutionGroup="xbrldt:hypercubeItem" />
<element name="AccruedExpensesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_AccruedExpensesLineItems" substitutionGroup="xbrli:item" />
<element name="AccruedClinicalTrialRunExpense" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="asmb_AccruedClinicalTrialRunExpense" substitutionGroup="xbrli:item" xbrli:balance="credit" />
<element name="StockholdersEquityNoteTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_StockholdersEquityNoteTable" substitutionGroup="xbrldt:hypercubeItem" />
<element name="PlanAxis" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_PlanAxis" substitutionGroup="xbrldt:dimensionItem" />
<element name="PlanDomain" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_PlanDomain" substitutionGroup="xbrli:item" />
<element name="StockholdersEquityNoteLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_StockholdersEquityNoteLineItems" substitutionGroup="xbrli:item" />
<element name="PeriodAxis" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_PeriodAxis" substitutionGroup="xbrldt:dimensionItem" />
<element name="PeriodDomain" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_PeriodDomain" substitutionGroup="xbrli:item" />
<element name="CurrentPeriodMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_CurrentPeriodMember" substitutionGroup="xbrli:item" />
<element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedInPeriodTotalIntrinsicValue" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedInPeriodTotalIntrinsicValue" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeitedInPeriodTotalIntrinsicValue" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeitedInPeriodTotalIntrinsicValue" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsMethodUsedLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsMethodUsedLineItems" substitutionGroup="xbrli:item" />
<element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedInPeriodFairValue1" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedInPeriodFairValue1" substitutionGroup="xbrli:item" xbrli:balance="credit" />
<element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairAmount" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="TwoThousandEighteenEmployeeStockPurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_TwoThousandEighteenEmployeeStockPurchasePlanMember" substitutionGroup="xbrli:item" />
<element name="DecemberTwentyThousandSeventeenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_DecemberTwentyThousandSeventeenMember" substitutionGroup="xbrli:item" />
<element name="DeferredRevenueMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_DeferredRevenueMember" substitutionGroup="xbrli:item" />
<element name="ChangeInContractWithCustomerLiabilityLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_ChangeInContractWithCustomerLiabilityLineItems" substitutionGroup="xbrli:item" />
<element name="ContractWithcustomerLiabiltyInAdditions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_ContractWithcustomerLiabiltyInAdditions" substitutionGroup="xbrli:item" xbrli:balance="credit" />
<element name="ContractWithCustomerLiabilityInDeductiion" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_ContractWithCustomerLiabilityInDeductiion" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="CollaborationRevenueRecognizedInPeriodAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_CollaborationRevenueRecognizedInPeriodAbstract" substitutionGroup="xbrli:item" />
<element name="AllerganPharmaceuticalsInternationalLimitedMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_AllerganPharmaceuticalsInternationalLimitedMember" substitutionGroup="xbrli:item" />
<element name="BusinessAcquisitionAgreementCounterPartyAxis" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_BusinessAcquisitionAgreementCounterPartyAxis" substitutionGroup="xbrldt:dimensionItem" />
<element name="BusinessAcquisitionAgreementCounterPartyDomain" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_BusinessAcquisitionAgreementCounterPartyDomain" substitutionGroup="xbrli:item" />
<element name="NewContractsAxis" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_NewContractsAxis" substitutionGroup="xbrldt:dimensionItem" />
<element name="NewContractsDomain" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_NewContractsDomain" substitutionGroup="xbrli:item" />
<element name="ProceedsFromUpfrontPayment" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_ProceedsFromUpfrontPayment" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="DescriptionOfAgreeToShareDevelopmentCost" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_DescriptionOfAgreeToShareDevelopmentCost" substitutionGroup="xbrli:item" />
<element name="RevenueRecognitionMultipleDeliverableArrangementsDeterminationsOfSellingPriceAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_RevenueRecognitionMultipleDeliverableArrangementsDeterminationsOfSellingPriceAmount" substitutionGroup="xbrli:item" xbrli:balance="credit" />
<element name="AgreedToShareAmountDevelopmentCost" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_AgreedToShareAmountDevelopmentCost" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="RevenueRecognitionMilestoneMethodsDescription" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_RevenueRecognitionMilestoneMethodsDescription" substitutionGroup="xbrli:item" />
<element name="CostOfReimbursableExpenses" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="asmb_CostOfReimbursableExpenses" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="IndianaUniversityResearchAndTechnologyCorporationMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="asmb_IndianaUniversityResearchAndTechnologyCorporationMember" substitutionGroup="xbrli:item" />
<element name="PotentialMilestonePayments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="asmb_PotentialMilestonePayments" substitutionGroup="xbrli:item" xbrli:balance="credit" />
</schema>
