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  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xsd:import namespace="http://fasb.org/srt/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/ecd-sub/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-sub-2025.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/cyd/2025" schemaLocation="https://xbrl.sec.gov/cyd/2025/cyd-2025.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/cyd-af-sub/2025" schemaLocation="https://xbrl.sec.gov/cyd/2025/cyd-af-sub-2025.xsd" />
  <xsd:element name="OtherCurrentReceivablesAbstract" id="aciu_OtherCurrentReceivablesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfOtherCurrentReceivablesTextBlock" id="aciu_DisclosureOfOtherCurrentReceivablesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ExpensesOperatingAbstract" id="aciu_ExpensesOperatingAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IssueOfEquityRestrictedShareAwards" id="aciu_IssueOfEquityRestrictedShareAwards" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="CashAdvancesForRentDeposit" id="aciu_CashAdvancesForRentDeposit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="ChangesInWorkingCapitalAbstract" id="aciu_ChangesInWorkingCapitalAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AdjustmentsForIncreaseDecreaseInAccruedExpenses" id="aciu_AdjustmentsForIncreaseDecreaseInAccruedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="AdjustmentsForDepreciationExpenseRightOfUseAssets" id="aciu_AdjustmentsForDepreciationExpenseRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="SupplementalNonCashActivityAbstract" id="aciu_SupplementalNonCashActivityAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PurchaseOfPropertyPlantAndEquipmentClassifiedAsNoncashInvestingActivities" id="aciu_PurchaseOfPropertyPlantAndEquipmentClassifiedAsNoncashInvestingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="ExpensesByCategoryAbstract" id="aciu_ExpensesByCategoryAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CommitmentsAndContingenciesAbstract" id="aciu_CommitmentsAndContingenciesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LaboratoryEquipmentMember" id="aciu_LaboratoryEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ConditionalShareCapitalForEmployeeBenefitPlansMember" id="aciu_ConditionalShareCapitalForEmployeeBenefitPlansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ConditionalShareCapitalAbstract" id="aciu_ConditionalShareCapitalAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PotentialNumberOfSharesIssuedFromShareBasedPaymentTransactions" id="aciu_PotentialNumberOfSharesIssuedFromShareBasedPaymentTransactions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
  <xsd:element name="PotentialIncreaseIsEquityThroughShareBasedPaymentTransactions" id="aciu_PotentialIncreaseIsEquityThroughShareBasedPaymentTransactions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="TaxLossesSplitByExpiryDateAbstract" id="aciu_TaxLossesSplitByExpiryDateAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AtTheMarketEquityOfferingAbstract" id="aciu_AtTheMarketEquityOfferingAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AtTheMarketEquityOfferingMember" id="aciu_AtTheMarketEquityOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SaleOrIssueOfTreasurySharesShares" id="aciu_SaleOrIssueOfTreasurySharesShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfOtherCurrentReceivablesTable" id="aciu_DisclosureOfOtherCurrentReceivablesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfOtherCurrentReceivablesLineItems" id="aciu_DisclosureOfOtherCurrentReceivablesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ScheduleOfContractualUndiscountedCashFlowsTableTextBlock" id="aciu_ScheduleOfContractualUndiscountedCashFlowsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfRightOfUseAssetsImpactOnStatementsTextBlock" id="aciu_DisclosureOfRightOfUseAssetsImpactOnStatementsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ImpactOnStatementsOfIncomeLossAndCashFlowsAbstract" id="aciu_ImpactOnStatementsOfIncomeLossAndCashFlowsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ContractualUndiscountedCashFlowsForLeaseLiabilitiesAbstract" id="aciu_ContractualUndiscountedCashFlowsForLeaseLiabilitiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EscrowDepositAmount" id="aciu_EscrowDepositAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="NumberOfDepositsInEscrowAccounts" id="aciu_NumberOfDepositsInEscrowAccounts" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
  <xsd:element name="RightOfUseLeasedAssetsAbstract" id="aciu_RightOfUseLeasedAssetsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ExpenseRelatingToLeases" id="aciu_ExpenseRelatingToLeases" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="CollaborationAndLicenseRevenueAgreementsMember" id="aciu_CollaborationAndLicenseRevenueAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OtherAgreementMember" id="aciu_OtherAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CollaborationAgreementWithLillyMember" id="aciu_CollaborationAgreementWithLillyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ContractRevenueAbstract" id="aciu_ContractRevenueAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LicenseAndCollaborationAgreementOf2014LifeMolecularImagingMember" id="aciu_LicenseAndCollaborationAgreementOf2014LifeMolecularImagingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CollaborationAgreementOf2014JanssenPharmaceuticalsMember" id="aciu_CollaborationAgreementOf2014JanssenPharmaceuticalsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CollaborativeAgreementMilestonePaymentReceived" id="aciu_CollaborativeAgreementMilestonePaymentReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="CollaborativeAgreementPotentialValue" id="aciu_CollaborativeAgreementPotentialValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="CollaborativeAgreementNoticeOfContractTerminationPeriod" id="aciu_CollaborativeAgreementNoticeOfContractTerminationPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SkaneUniversityHospitalMember" id="aciu_SkaneUniversityHospitalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="GrantRevenueMember" id="aciu_GrantRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="GrantsMichaelJFoxFoundationMember" id="aciu_GrantsMichaelJFoxFoundationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfGrants" id="aciu_NumberOfGrants" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfRepresentativesInJointSteeringCommitteeByEachParty" id="aciu_NumberOfRepresentativesInJointSteeringCommitteeByEachParty" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CollaborativeAgreementMilestonePaymentNumberOfInstallments" id="aciu_CollaborativeAgreementMilestonePaymentNumberOfInstallments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TauMorphomerSmallMoleculeMember" id="aciu_TauMorphomerSmallMoleculeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="RightOfUseLicenseMember" id="aciu_RightOfUseLicenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ResearchAndDevelopmentMember" id="aciu_ResearchAndDevelopmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="MilestonePaymentsClinicalAndRegulatoryMilestonesMember" id="aciu_MilestonePaymentsClinicalAndRegulatoryMilestonesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="MilestonePaymentsCommercialMember" id="aciu_MilestonePaymentsCommercialMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CollaborationAgreementWithLillyFirstAmendmentMember" id="aciu_CollaborationAgreementWithLillyFirstAmendmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CollaborationAgreementWithLillySecondAmendmentMember" id="aciu_CollaborationAgreementWithLillySecondAmendmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BasisOfPreparationAbstract" id="aciu_BasisOfPreparationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="GoingConcernAbstract" id="aciu_GoingConcernAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutIncomeTaxReconciliationTableTextBlock" id="aciu_DisclosureOfDetailedInformationAboutIncomeTaxReconciliationTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutIncomeTaxLossesExpiryTableTextBlock" id="aciu_DisclosureOfDetailedInformationAboutIncomeTaxLossesExpiryTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TauVaccineInADMember" id="aciu_TauVaccineInADMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="GeneralInformationAbstract" id="aciu_GeneralInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfGeneralInformationAboutTheEntityExplanatoryTextBlock" id="aciu_DisclosureOfGeneralInformationAboutTheEntityExplanatoryTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfTechnologyPlatforms" id="aciu_NumberOfTechnologyPlatforms" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
  <xsd:element name="FinancialResultNetAbstract" id="aciu_FinancialResultNetAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfInformationAboutCommitmentsAndContingenciesTable" id="aciu_DisclosureOfInformationAboutCommitmentsAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfInformationAboutCommitmentsAndContingenciesLineItems" id="aciu_DisclosureOfInformationAboutCommitmentsAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CommitmentsAbstract" id="aciu_CommitmentsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfPerformanceObligationsIdentified" id="aciu_NumberOfPerformanceObligationsIdentified" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageAssumptionsAbstract" id="aciu_WeightedAverageAssumptionsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OtherComprehensiveGainsLossesAbstract" id="aciu_OtherComprehensiveGainsLossesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EstimatedLeaseTerm" id="aciu_EstimatedLeaseTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LeaseholdImprovementsAndFixturesAndFittingsMember" id="aciu_LeaseholdImprovementsAndFixturesAndFittingsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PropertyPlantAndEquipmentEstimatedUsefulLifeAbstract" id="aciu_PropertyPlantAndEquipmentEstimatedUsefulLifeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OperatingSegmentsNumber" id="aciu_OperatingSegmentsNumber" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ReportableSegmentsNumber" id="aciu_ReportableSegmentsNumber" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ScheduleOfInformationAboutContractLeaseTermByRightOfUseAssetCategoriesTableTextBlock" id="aciu_ScheduleOfInformationAboutContractLeaseTermByRightOfUseAssetCategoriesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ScheduleOfInformationAboutPropertyPlantAndEquipmentUsefulLifeTableTextBlock" id="aciu_ScheduleOfInformationAboutPropertyPlantAndEquipmentUsefulLifeTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TauPETImagingAgentMember" id="aciu_TauPETImagingAgentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CurrentAccruedResearchAndDevelopmentCosts" id="aciu_CurrentAccruedResearchAndDevelopmentCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="NumberOfPersonsKeyManagementBoardOfDirectors" id="aciu_NumberOfPersonsKeyManagementBoardOfDirectors" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfPersonsKeyManagementExecutiveManagement" id="aciu_NumberOfPersonsKeyManagementExecutiveManagement" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutTradePayablesAndAccruedLiabilitiesTableTextBlock" id="aciu_DisclosureOfDetailedInformationAboutTradePayablesAndAccruedLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfNonVestedSharesAbstract" id="aciu_NumberOfNonVestedSharesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfOtherEquityInstrumentsExercisedInShareBasedPaymentArrangement" id="aciu_NumberOfOtherEquityInstrumentsExercisedInShareBasedPaymentArrangement" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedPaymentArrangementAbstract" id="aciu_ShareBasedPaymentArrangementAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="MaximumTermOfOtherEquityInstrumentsGrantedForShareBasedPaymentArrangement" id="aciu_MaximumTermOfOtherEquityInstrumentsGrantedForShareBasedPaymentArrangement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BoardOfDirectorsMember" id="aciu_BoardOfDirectorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="VestingRequirementsForShareBasedPaymentArrangementAwardVestingPeriod" id="aciu_VestingRequirementsForShareBasedPaymentArrangementAwardVestingPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ExecutiveManagementMember" id="aciu_ExecutiveManagementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageExercisePriceAbstract" id="aciu_WeightedAverageExercisePriceAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SensitivityAnalysisActuarialAssumptionsAbstract" id="aciu_SensitivityAnalysisActuarialAssumptionsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PercentageOfReasonablyPossibleDecreaseInActuarialAssumptionMember" id="aciu_PercentageOfReasonablyPossibleDecreaseInActuarialAssumptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PercentageOfReasonablyPossibleIncreaseInActuarialAssumptionMember" id="aciu_PercentageOfReasonablyPossibleIncreaseInActuarialAssumptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ChangesInFairValueOfPlanAssetsAbstract" id="aciu_ChangesInFairValueOfPlanAssetsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfOptionsAbstract" id="aciu_NumberOfOptionsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageRemainingAbstract" id="aciu_WeightedAverageRemainingAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="FinancialAssetsAndLiabilitiesAbstract" id="aciu_FinancialAssetsAndLiabilitiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AccruedExpensesMember" id="aciu_AccruedExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TradeAndOtherPayablesMember" id="aciu_TradeAndOtherPayablesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="FinancialRisksAbstract" id="aciu_FinancialRisksAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfFinancialInstitutionsHoldingCashAndCashEquivalentsAndShortTermFinancialAssets" id="aciu_NumberOfFinancialInstitutionsHoldingCashAndCashEquivalentsAndShortTermFinancialAssets" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LongTermFinancialAssetsMember" id="aciu_LongTermFinancialAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CashOnHandAndCashEquivalentsMember" id="aciu_CashOnHandAndCashEquivalentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShortTermFinancialAssetsMember" id="aciu_ShortTermFinancialAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShortTermLeaseLiabilitiesMember" id="aciu_ShortTermLeaseLiabilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutCarryingAmountsOfFinancialAssetsAndFinancialLiabilitiesTableTextBlock" id="aciu_DisclosureOfDetailedInformationAboutCarryingAmountsOfFinancialAssetsAndFinancialLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="OutstandingOptionsExercisePriceRangeAndExpiryDatesAbstract" id="aciu_OutstandingOptionsExercisePriceRangeAndExpiryDatesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfEquityBasedInstrumentPlans" id="aciu_NumberOfEquityBasedInstrumentPlans" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockOptionPlanC1Member" id="aciu_StockOptionPlanC1Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="Two016ShareOptionAndIncentivePlanMember" id="aciu_Two016ShareOptionAndIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="Two016ShareOptionAndIncentivePlanVestingTrancheOneMember" id="aciu_Two016ShareOptionAndIncentivePlanVestingTrancheOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="Two016ShareOptionAndIncentivePlanVestingTrancheTwoMember" id="aciu_Two016ShareOptionAndIncentivePlanVestingTrancheTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedPlansOutstandingAbstract" id="aciu_ShareBasedPlansOutstandingAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="MaximumTermOfOptionsGrantedForShareBasedPaymentArrangement" id="aciu_MaximumTermOfOptionsGrantedForShareBasedPaymentArrangement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EmployeesMember" id="aciu_EmployeesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="Two016ShareOptionAndIncentivePlanVestingTrancheThreeMember" id="aciu_Two016ShareOptionAndIncentivePlanVestingTrancheThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncomeTaxLossCarryforwardPeriod" id="aciu_IncomeTaxLossCarryforwardPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PrepaidExpensesAndAccruedIncomeDisclosureAbstract" id="aciu_PrepaidExpensesAndAccruedIncomeDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="FairValueOfFinancialAssetsAndLiabilitiesPolicyTextBlock" id="aciu_FairValueOfFinancialAssetsAndLiabilitiesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DescriptionOfAccountingPolicyForAccountingJudgmentsAndEstimatesPolicyTextBlock" id="aciu_DescriptionOfAccountingPolicyForAccountingJudgmentsAndEstimatesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="GrantIncomePolicyTextBlock" id="aciu_GrantIncomePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DescriptionOfAccountingPolicyForClassificationOfAssetsAndLiabilitiesPolicyTextBlock" id="aciu_DescriptionOfAccountingPolicyForClassificationOfAssetsAndLiabilitiesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CashAndCashEquivalentsTable" id="aciu_CashAndCashEquivalentsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CashAndCashEquivalentLineItems" id="aciu_CashAndCashEquivalentLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="InProcessResearchAndDevelopmentIPRDAssetMember" id="aciu_InProcessResearchAndDevelopmentIPRDAssetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncreaseInNumberOfOrdinarySharesIssuedUnderIncentivePlans" id="aciu_IncreaseInNumberOfOrdinarySharesIssuedUnderIncentivePlans" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncreaseThroughSharesIssuedUnderIncentivePlans" id="aciu_IncreaseThroughSharesIssuedUnderIncentivePlans" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutOtherCurrentReceivablesTableTextBlock" id="aciu_DisclosureOfDetailedInformationAboutOtherCurrentReceivablesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PaymentsProceedsFromPurchasesSalesOfShortTermFinancialAssetsClassifiedAsInvestingActivities" id="aciu_PaymentsProceedsFromPurchasesSalesOfShortTermFinancialAssetsClassifiedAsInvestingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="WithholdingTaxReceivables" id="aciu_WithholdingTaxReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="AccruedExpensesAbstract" id="aciu_AccruedExpensesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AlphaSynucleinPetImagingDiagnosticAgentMember" id="aciu_AlphaSynucleinPetImagingDiagnosticAgentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="FollowOnGrantFundingReceived" id="aciu_FollowOnGrantFundingReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="FollowOnGrantFundingReceivedTotalForJointArrangement" id="aciu_FollowOnGrantFundingReceivedTotalForJointArrangement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="ProceedsFromSaleOfTreasurySharesInPublicOfferingsNetOfUnderwritingFeesAndTransactionCosts" id="aciu_ProceedsFromSaleOfTreasurySharesInPublicOfferingsNetOfUnderwritingFeesAndTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="AssetAcquisitionsAxis" id="aciu_AssetAcquisitionsAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SignificantAssetAcquisitionsTotalDomain" id="aciu_SignificantAssetAcquisitionsTotalDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SignificantAssetAcquisitionsAxis" id="aciu_SignificantAssetAcquisitionsAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AllSignificantAssetAcquisitionsDomain" id="aciu_AllSignificantAssetAcquisitionsDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="MiscellaneousOtherCurrentReceivables" id="aciu_MiscellaneousOtherCurrentReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="MaturityPeriodOtherCurrentReceivables" id="aciu_MaturityPeriodOtherCurrentReceivables" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ReconciliationOfNumberOfTreasurySharesOutstandingAbstract" id="aciu_ReconciliationOfNumberOfTreasurySharesOutstandingAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PotentialIncreaseIsEquityThroughConversionOfDebtInstruments" id="aciu_PotentialIncreaseIsEquityThroughConversionOfDebtInstruments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="PotentialNumberOfSharesIssuedFromConversionOfDebtInstruments" id="aciu_PotentialNumberOfSharesIssuedFromConversionOfDebtInstruments" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
  <xsd:element name="CapitalAuthorizedToBeIssuedUnderShelfRegistrationStatement" id="aciu_CapitalAuthorizedToBeIssuedUnderShelfRegistrationStatement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="OtherAccruedExpenses" id="aciu_OtherAccruedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="Quarter32019Member" id="aciu_Quarter32019Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="March312020Member" id="aciu_March312020Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="UponFirstPatientDosedInPhase2ClinicalStudyOfLicensedProductInU.s.OrEu.Member" id="aciu_UponFirstPatientDosedInPhase2ClinicalStudyOfLicensedProductInU.s.OrEu.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="CollaborativeAgreementUpfrontPaymentsReceived" id="aciu_CollaborativeAgreementUpfrontPaymentsReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="AdvanceSmallMoleculePdProgramsMember" id="aciu_AdvanceSmallMoleculePdProgramsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ResearchAndDevelopmentExpensesMember" id="aciu_ResearchAndDevelopmentExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EmployeeBenefitsExpenseExcludingShareBasedCompensation" id="aciu_EmployeeBenefitsExpenseExcludingShareBasedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="TaxEffectOfIncomeNotSubjectToTaxAndExpensesNotDeductibleForTaxPurposes" id="aciu_TaxEffectOfIncomeNotSubjectToTaxAndExpensesNotDeductibleForTaxPurposes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="RetirementBenefitPlanMember" id="aciu_RetirementBenefitPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="December312025Member" id="aciu_December312025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="December312027Member" id="aciu_December312027Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="December312028Member" id="aciu_December312028Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="December312029Member" id="aciu_December312029Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncreaseDecreaseInTaxLossesAvailableForOffsetAgainstFutureTaxableProfits" id="aciu_IncreaseDecreaseInTaxLossesAvailableForOffsetAgainstFutureTaxableProfits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="DefinedBenefitPlansPercentageOfContributionsByEmployees" id="aciu_DefinedBenefitPlansPercentageOfContributionsByEmployees" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DefinedBenefitPlansPercentageOfContributionsByEmployer" id="aciu_DefinedBenefitPlansPercentageOfContributionsByEmployer" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncreaseDecreaseInNetDefinedBenefitLiabilityAssetResultingFromBenefitsDeposited" id="aciu_IncreaseDecreaseInNetDefinedBenefitLiabilityAssetResultingFromBenefitsDeposited" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="ActuarialAssumptionOfInterestRateOnRetirementSavingsCapital" id="aciu_ActuarialAssumptionOfInterestRateOnRetirementSavingsCapital" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant" />
  <xsd:element name="ActuarialAssumptionOfInterestRateOnSavingsCapitalMember" id="aciu_ActuarialAssumptionOfInterestRateOnSavingsCapitalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageRemainingContractualLifeOfShareOptionsExercisable" id="aciu_WeightedAverageRemainingContractualLifeOfShareOptionsExercisable" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="Chf0.15Member" id="aciu_Chf0.15Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="Chf9.53Member" id="aciu_Chf9.53Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="RestrictedStockUnitsFirstVestingConditionsMember" id="aciu_RestrictedStockUnitsFirstVestingConditionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="RestrictedStockUnitsSecondVestingConditionsMember" id="aciu_RestrictedStockUnitsSecondVestingConditionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageGrantDateFairValueOtherEquityInstrumentsOutstanding" id="aciu_WeightedAverageGrantDateFairValueOtherEquityInstrumentsOutstanding" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="WeightedAverageGrantDateFairValueOtherEquityInstrumentsForfeited" id="aciu_WeightedAverageGrantDateFairValueOtherEquityInstrumentsForfeited" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageGrantDateFairValueOtherEquityInstrumentsExpired" id="aciu_WeightedAverageGrantDateFairValueOtherEquityInstrumentsExpired" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageGrantDateFairValueOtherEquityInstrumentsExercised" id="aciu_WeightedAverageGrantDateFairValueOtherEquityInstrumentsExercised" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageGrantDateFairValueOtherEquityInstrumentsGranted" id="aciu_WeightedAverageGrantDateFairValueOtherEquityInstrumentsGranted" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageGrantDateFairValueOtherEquityInstrumentsVested" id="aciu_WeightedAverageGrantDateFairValueOtherEquityInstrumentsVested" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageGrantDateFairValueOtherEquityInstrumentsVestedAndExercisable" id="aciu_WeightedAverageGrantDateFairValueOtherEquityInstrumentsVestedAndExercisable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element name="OtherCurrentReceivablesMember" id="aciu_OtherCurrentReceivablesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="LongTermLeaseLiabilitiesMember" id="aciu_LongTermLeaseLiabilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PercentageOfReasonablyPossibleStrengtheningOrWeakeningOfReportingCurrencyAgainstOtherRelevantCurrencies" id="aciu_PercentageOfReasonablyPossibleStrengtheningOrWeakeningOfReportingCurrencyAgainstOtherRelevantCurrencies" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PercentageOfReasonablyPossibleIncreaseOrDecreaseInInterestRates" id="aciu_PercentageOfReasonablyPossibleIncreaseOrDecreaseInInterestRates" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IncreaseDecreaseInProfitLossResultingFromReasonablyPossibleStrengtheningOrWeakeningOfReportingCurrencyAgainstOtherRelevantCurrencies" id="aciu_IncreaseDecreaseInProfitLossResultingFromReasonablyPossibleStrengtheningOrWeakeningOfReportingCurrencyAgainstOtherRelevantCurrencies" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="IncreaseDecreaseInProfitLossResultingFromReasonablyPossibleIncreaseOrDecreaseInInterestRates" id="aciu_IncreaseDecreaseInProfitLossResultingFromReasonablyPossibleIncreaseOrDecreaseInInterestRates" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="ScheduleOfCashAndCashEquivalentsByCurrencyTableTextBlock" id="aciu_ScheduleOfCashAndCashEquivalentsByCurrencyTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfAmountsRecognisedInBalanceSheetFromDefinedBenefitPlansTableTextBlock" id="aciu_DisclosureOfAmountsRecognisedInBalanceSheetFromDefinedBenefitPlansTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfAmountsRecognisedInStatementOfProfitAndLossFromDefinedBenefitPlansTableTextBlock" id="aciu_DisclosureOfAmountsRecognisedInStatementOfProfitAndLossFromDefinedBenefitPlansTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfAmountsRecognisedInStatementOfOtherComprehensiveIncomeFromDefinedBenefitPlansTableTextBlock" id="aciu_DisclosureOfAmountsRecognisedInStatementOfOtherComprehensiveIncomeFromDefinedBenefitPlansTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SaleOrIssueOfTreasurySharesNetOfUnderwritingFeesAndTransactionCosts" id="aciu_SaleOrIssueOfTreasurySharesNetOfUnderwritingFeesAndTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfCashAndCashEquivalentsAndShortTermDepositsNotClassifiedAsCashEquivalentsTextBlock" id="aciu_DisclosureOfCashAndCashEquivalentsAndShortTermDepositsNotClassifiedAsCashEquivalentsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ScheduleOfShortTermDepositsNotClassifiedAsCashEquivalentsTableTextBlock" id="aciu_ScheduleOfShortTermDepositsNotClassifiedAsCashEquivalentsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfTradeAndOtherPayablesAndAccruedExpensesTextBlock" id="aciu_DisclosureOfTradeAndOtherPayablesAndAccruedExpensesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfPrepaidExpensesAndAccruedIncomeIncludingContractAssetsTextBlock" id="aciu_DisclosureOfPrepaidExpensesAndAccruedIncomeIncludingContractAssetsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DisclosureOfDetailedInformationAboutPrepaidExpensesAndAccruedIncomeIncludingContractAssetsTableTextBlock" id="aciu_DisclosureOfDetailedInformationAboutPrepaidExpensesAndAccruedIncomeIncludingContractAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TransactionCostsAssociatedWithSaleOfTreasurySharesInPublicOfferingRecordedInAccruedExpenses" id="aciu_TransactionCostsAssociatedWithSaleOfTreasurySharesInPublicOfferingRecordedInAccruedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="AdditionalGrantAwarded" id="aciu_AdditionalGrantAwarded" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="NumberOfTreasurySharesSoldDuringPeriod" id="aciu_NumberOfTreasurySharesSoldDuringPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="December312030Member" id="aciu_December312030Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="SaleOrIssueOfPublicOfferingsNetOfUnderwritingFeesTransactionCost" id="aciu_SaleOrIssueOfPublicOfferingsNetOfUnderwritingFeesTransactionCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element name="ProceedsFromIssuanceOfPublicOfferingsOfCommonSharesNetOfUnderwritingFeesAndTransactionCosts" id="aciu_ProceedsFromIssuanceOfPublicOfferingsOfCommonSharesNetOfUnderwritingFeesAndTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="TransactionCostAndStampDutyAssociatedWithPublicOfferingsOfCommonSharesRecordedInAccruedExpenses" id="aciu_TransactionCostAndStampDutyAssociatedWithPublicOfferingsOfCommonSharesRecordedInAccruedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="FollowOnOfferingMember" id="aciu_FollowOnOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="IfrsSubsequentEventTypeAxis" id="aciu_IfrsSubsequentEventTypeAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IfrsSubsequentEventTypeDomain" id="aciu_IfrsSubsequentEventTypeDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfSharesIssuedDuringPeriod" id="aciu_NumberOfSharesIssuedDuringPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NetProceedsFromIssuanceOfShares" id="aciu_NetProceedsFromIssuanceOfShares" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ConditionalShareCapitalForFinancingAndOtherPurposesMember" id="aciu_ConditionalShareCapitalForFinancingAndOtherPurposesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PaymentsForShareIssueCostsAndStampDutyAssociatedWithPublicOfferings" id="aciu_PaymentsForShareIssueCostsAndStampDutyAssociatedWithPublicOfferings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PaymentsForShareIssueCostsAssociatedWithSaleOfTreasurySharesInPublicOfferings" id="aciu_PaymentsForShareIssueCostsAssociatedWithSaleOfTreasurySharesInPublicOfferings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AntiAbetaActiveImmunotherapyInAd2024AgreementTakedaPharmaceuticalsUsaInc.Member" id="aciu_AntiAbetaActiveImmunotherapyInAd2024AgreementTakedaPharmaceuticalsUsaInc.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseOptionMember" id="aciu_LicenseOptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LicenseOptionAndDevelopmentCmcAndRegulatoryActivitiesMember" id="aciu_LicenseOptionAndDevelopmentCmcAndRegulatoryActivitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DevelopmentCmcAndRegulatoryActivitiesMember" id="aciu_DevelopmentCmcAndRegulatoryActivitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CollaborativeAgreementPotentialReceivablesForOptionExerciseFeeAndPotentialDevelopmentCommercialAndSalesBasedMilestones" id="aciu_CollaborativeAgreementPotentialReceivablesForOptionExerciseFeeAndPotentialDevelopmentCommercialAndSalesBasedMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NumberOfDevelopmentMilestonesThatMayOccurPriorToOptionExerciseIncludedInTransactionPrice" id="aciu_NumberOfDevelopmentMilestonesThatMayOccurPriorToOptionExerciseIncludedInTransactionPrice" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="AdjustmentsForIncreaseDecreaseInCurrentContractLiabilities" id="aciu_AdjustmentsForIncreaseDecreaseInCurrentContractLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AdjustmentsForIncreaseDecreaseInNonCurrentContractLiabilities" id="aciu_AdjustmentsForIncreaseDecreaseInNonCurrentContractLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ProceedsFromIssuanceOfSharesThroughEquityPlansNetOfTransactionCosts" id="aciu_ProceedsFromIssuanceOfSharesThroughEquityPlansNetOfTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AccruedInterestIncome" id="aciu_AccruedInterestIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NumberOfSharesIssuedInPublicOfferings" id="aciu_NumberOfSharesIssuedInPublicOfferings" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DecreaseInNumberOfTreasurySharesThroughEquityIncentivePlans" id="aciu_DecreaseInNumberOfTreasurySharesThroughEquityIncentivePlans" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IfrsSaleOfStockAxis" id="aciu_IfrsSaleOfStockAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IfrsSaleOfStockDomain" id="aciu_IfrsSaleOfStockDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ValueOfSharesAuthorizedForIssueInOffering" id="aciu_ValueOfSharesAuthorizedForIssueInOffering" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInFinanceIncomeExpenseComparedToPriorPeriod" id="aciu_IncreaseDecreaseInFinanceIncomeExpenseComparedToPriorPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncreaseDecreaseInFinanceIncomeComparedToPriorPeriod" id="aciu_IncreaseDecreaseInFinanceIncomeComparedToPriorPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="December312031Member" id="aciu_December312031Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Usd2.03ToUsd3.00Member" id="aciu_Usd2.03ToUsd3.00Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Usd3.00ToUsd6.00Member" id="aciu_Usd3.00ToUsd6.00Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Usd6.00ToUsd9.00Member" id="aciu_Usd6.00ToUsd9.00Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Usd9.00ToUsd12.30Member" id="aciu_Usd9.00ToUsd12.30Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TaxLossesExpiredDuringPeriod" id="aciu_TaxLossesExpiredDuringPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IfrsRestructuringAndRelatedActivitiesAbstract" id="aciu_IfrsRestructuringAndRelatedActivitiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IfrsRestructuringAndRelatedActivitiesDisclosureTextBlock" id="aciu_IfrsRestructuringAndRelatedActivitiesDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="December312032Member" id="aciu_December312032Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AdjustmentsForGainLossOnLeaseModifications" id="aciu_AdjustmentsForGainLossOnLeaseModifications" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DescriptionOfAccountingPolicyForRestructuringExpensePolicyTextBlock" id="aciu_DescriptionOfAccountingPolicyForRestructuringExpensePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NumberOfCoreValueDriversInCorporateStrategy" id="aciu_NumberOfCoreValueDriversInCorporateStrategy" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ExpenseFromAccelerationOfShareBasedPaymentExpense" id="aciu_ExpenseFromAccelerationOfShareBasedPaymentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NumberOfSharesIssuedThatHaveNotYetBeenRegisteredInCommercialRegister" id="aciu_NumberOfSharesIssuedThatHaveNotYetBeenRegisteredInCommercialRegister" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ContractualNoticePeriodInLeaseAgreements" id="aciu_ContractualNoticePeriodInLeaseAgreements" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="OperatingExpenseExcludingEmployeeBenefitsExpenseAndDepreciation" id="aciu_OperatingExpenseExcludingEmployeeBenefitsExpenseAndDepreciation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
</xsd:schema>
