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  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledWeightedAverageGrantDateFairValue" id="btai_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCancelledWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="TrancheDMember" id="btai_TrancheDMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LineOfCreditFacilityExitFeePercentage" id="btai_LineOfCreditFacilityExitFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LineOfCreditFacilityAmendmentFeePercentage" id="btai_LineOfCreditFacilityAmendmentFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LineOfCreditFacilityInvestmentAllowed" id="btai_LineOfCreditFacilityInvestmentAllowed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AccountsReceivablePaymentTerm" id="btai_AccountsReceivablePaymentTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DebtInstrumentFinancialCovenantMinimumLiquidityRequirement" id="btai_DebtInstrumentFinancialCovenantMinimumLiquidityRequirement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NewWarrantsMember" id="btai_NewWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TrancheTwoMember" id="btai_TrancheTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SaleOfStockMaximumValueSharesToBeIssued" id="btai_SaleOfStockMaximumValueSharesToBeIssued" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FromAndAfterSatisfactionOfFundingConditionsForTrancheCLoansMember" id="btai_FromAndAfterSatisfactionOfFundingConditionsForTrancheCLoansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FromAndAfterFundingOfTrancheBLoansMember" id="btai_FromAndAfterFundingOfTrancheBLoansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="MinimumGrossProceedsFromIssuanceOfCommonStockWarrantsAndOrPreFundedWarrantsForDebt" id="btai_MinimumGrossProceedsFromIssuanceOfCommonStockWarrantsAndOrPreFundedWarrantsForDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="Warrants2024Member" id="btai_Warrants2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DebtInstrumentIncrementalOnVariableRatePercent" id="btai_DebtInstrumentIncrementalOnVariableRatePercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PeriodOneMember" id="btai_PeriodOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PeriodTwoMember" id="btai_PeriodTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PeriodThreeMember" id="btai_PeriodThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Warrants2024AccompanyingWarrantsMember" id="btai_Warrants2024AccompanyingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RegisteredDirectOfferingMember" id="btai_RegisteredDirectOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RestrictedStockUnitsVesting25PercentAtOneYearAndRemainingIn12QuartersMember" id="btai_RestrictedStockUnitsVesting25PercentAtOneYearAndRemainingIn12QuartersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CustomerOneMember" id="btai_CustomerOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ReverseStockSplit" id="btai_ReverseStockSplit" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SingleReportableSegmentMember" id="btai_SingleReportableSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EliminationsAndReconcilingItemsMember" id="btai_EliminationsAndReconcilingItemsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ResearchAndDevelopmentExpenseLaborAndRelatedExpense" id="btai_ResearchAndDevelopmentExpenseLaborAndRelatedExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseShareBasedPaymentArrangementExpense" id="btai_ResearchAndDevelopmentExpenseShareBasedPaymentArrangementExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseProfessionalFees" id="btai_ResearchAndDevelopmentExpenseProfessionalFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseClinicalTrialsExpense" id="btai_ResearchAndDevelopmentExpenseClinicalTrialsExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentExpenseChemicalManufacturingAndControlsExpense" id="btai_ResearchAndDevelopmentExpenseChemicalManufacturingAndControlsExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SellingGeneralAndAdministrativeExpenseLaborAndRelatedExpense" id="btai_SellingGeneralAndAdministrativeExpenseLaborAndRelatedExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SellingGeneralAndAdministrativeExpenseShareBasedPaymentArrangementExpense" id="btai_SellingGeneralAndAdministrativeExpenseShareBasedPaymentArrangementExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SellingGeneralAndAdministrativeExpenseProfessionalFees" id="btai_SellingGeneralAndAdministrativeExpenseProfessionalFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SellingGeneralAndAdministrativeExpenseTravelAndOtherExpenses" id="btai_SellingGeneralAndAdministrativeExpenseTravelAndOtherExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="November2024AccompanyingWarrantsMember" id="btai_November2024AccompanyingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockIssuedDuringPeriodSharesWarrantsExercised" id="btai_StockIssuedDuringPeriodSharesWarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="November2024PrefundedAccompanyingWarrantsMember" id="btai_November2024PrefundedAccompanyingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DeferredTaxAssetsCapitalizedIpoCosts" id="btai_DeferredTaxAssetsCapitalizedIpoCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DebtInstrumentQuarterlyAmortizationPaymentsAsPercentageOfPrincipalAmountFunded" id="btai_DebtInstrumentQuarterlyAmortizationPaymentsAsPercentageOfPrincipalAmountFunded" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="MaximumPercentageOfBudgetedAmountForDisbursementsInApplicablePeriod" id="btai_MaximumPercentageOfBudgetedAmountForDisbursementsInApplicablePeriod" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="Warrants2024AccompanyingWarrantsStrikePriceAmendedMember" id="btai_Warrants2024AccompanyingWarrantsStrikePriceAmendedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AccompanyingWarrants2024StrikePriceNotAmendedMember" id="btai_AccompanyingWarrants2024StrikePriceNotAmendedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AccompanyingWarrantsMarch2025Member" id="btai_AccompanyingWarrantsMarch2025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OptionWarrantsMarch2025Member" id="btai_OptionWarrantsMarch2025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BioxcelWarrantsAggregateMember" id="btai_BioxcelWarrantsAggregateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Warrants2023Member" id="btai_Warrants2023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WarrantShares2024Member" id="btai_WarrantShares2024Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AdjustmentsToAdditionalPaidInCapitalPreFundedWarrantIssued" id="btai_AdjustmentsToAdditionalPaidInCapitalPreFundedWarrantIssued" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ArmisticeCapitalMasterFundMember" id="btai_ArmisticeCapitalMasterFundMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="HeightsCapitalManagementMember" id="btai_HeightsCapitalManagementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="HudsonBayCapitalManagementMember" id="btai_HudsonBayCapitalManagementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IntraCoastalCapitalMember" id="btai_IntraCoastalCapitalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationWarrantValuationPercent" id="btai_EffectiveIncomeTaxRateReconciliationWarrantValuationPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationWarrantValuationAmount" id="btai_EffectiveIncomeTaxRateReconciliationWarrantValuationAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OriginalWarrantsMember" id="btai_OriginalWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CommercialCostsLaborAndRelatedExpense" id="btai_CommercialCostsLaborAndRelatedExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CommercialCostsShareBasedPaymentArrangementExpense" id="btai_CommercialCostsShareBasedPaymentArrangementExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CommercialCostsProfessionalFees" id="btai_CommercialCostsProfessionalFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CommercialCostsCommercialAndMarketing" id="btai_CommercialCostsCommercialAndMarketing" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CommercialCostsTravelAndOtherExpenses" id="btai_CommercialCostsTravelAndOtherExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ResearchAndDevelopmentCostsOtherExpenses" id="btai_ResearchAndDevelopmentCostsOtherExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CommercialCostsOtherExpenses" id="btai_CommercialCostsOtherExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SellingGeneralAndAdministrativeCostsOtherExpenses" id="btai_SellingGeneralAndAdministrativeCostsOtherExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RetentionBonusExpense" id="btai_RetentionBonusExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearTwo" id="btai_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearTwo" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="March2024AccompanyingWarrantsMember" id="btai_March2024AccompanyingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2024PreFundedWarrantsMember" id="btai_March2024PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2025AccompanyingWarrantsMember" id="btai_March2025AccompanyingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2025PrefundedWarrantsMember" id="btai_March2025PrefundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2025OfferingMember" id="btai_March2025OfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Warrants2025AccompanyingWarrantsMember" id="btai_Warrants2025AccompanyingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PurchaseObligationPriorYear" id="btai_PurchaseObligationPriorYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ClassOfWarrantOrRightOfferingPriceOfWarrantsOrRights" id="btai_ClassOfWarrantOrRightOfferingPriceOfWarrantsOrRights" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="AtMarketOfferingMember" id="btai_AtMarketOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CanaccordGenuityLlcMember" id="btai_CanaccordGenuityLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersLevel1ToLevel2" id="btai_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersLevel1ToLevel2" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersLevel2ToLevel1" id="btai_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersLevel2ToLevel1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersLevel1ToLevel2" id="btai_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersLevel1ToLevel2" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="NumberOfInstallmentsForPaymentOfRetentionBonus" id="btai_NumberOfInstallmentsForPaymentOfRetentionBonus" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RevenueCurePaymentMinimum" id="btai_RevenueCurePaymentMinimum" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EquityDistributionAgreementIncreasedMaximumMember" id="btai_EquityDistributionAgreementIncreasedMaximumMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EquityDistributionAgreementPursuantToFiledProspectusMember" id="btai_EquityDistributionAgreementPursuantToFiledProspectusMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ReclassificationOfDerivativeLiabilitiesToPermanentEquity" id="btai_ReclassificationOfDerivativeLiabilitiesToPermanentEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="VimalMehtaMember" id="btai_VimalMehtaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RichardSteinhartMember" id="btai_RichardSteinhartMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="JavierRodriguezMember" id="btai_JavierRodriguezMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FrankYoccaMember" id="btai_FrankYoccaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RelatedPartyTransactionsPolicyPolicyTextBlock" id="btai_RelatedPartyTransactionsPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LitigationSettlementLiabilityAndRelatedInsuranceRecovery" id="btai_LitigationSettlementLiabilityAndRelatedInsuranceRecovery" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RepricingOfStockPurchaseWarrants" id="btai_RepricingOfStockPurchaseWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="March2026OfferingMember" id="btai_March2026OfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2026AccompanyingWarrantsMember" id="btai_March2026AccompanyingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2026PreFundedWarrantsMember" id="btai_March2026PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2026PreFundedAccompanyingWarrantsMember" id="btai_March2026PreFundedAccompanyingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PlacementAgentWarrantsMember" id="btai_PlacementAgentWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WarrantAmendmentRelatesToMarchAndNovember2024WarrantsMember" id="btai_WarrantAmendmentRelatesToMarchAndNovember2024WarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfSharesAgreedToBeIssued" id="btai_NumberOfSharesAgreedToBeIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="SharesAndWarrantsCombinedOfferingPrice" id="btai_SharesAndWarrantsCombinedOfferingPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PreFundedAndAccompanyingWarrantsCombinedOfferingPrice" id="btai_PreFundedAndAccompanyingWarrantsCombinedOfferingPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PlacementAgentFeesPercentageOfGrossProceeds" id="btai_PlacementAgentFeesPercentageOfGrossProceeds" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PlacementAgentCompensationPercentageOfShares" id="btai_PlacementAgentCompensationPercentageOfShares" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PlacementAgentExercisePricePercentageOfOfferingPrice" id="btai_PlacementAgentExercisePricePercentageOfOfferingPrice" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PlacementAgentPricePerShareToExerciseWarrants" id="btai_PlacementAgentPricePerShareToExerciseWarrants" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PlacementAgentMaximumReimbursementOfExpenses" id="btai_PlacementAgentMaximumReimbursementOfExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PlacementAgentMaximumReimbursementOfClearingAndClosingExpenses" id="btai_PlacementAgentMaximumReimbursementOfClearingAndClosingExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="WarrantAmendmentConsideration" id="btai_WarrantAmendmentConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OperatingLeaseMonthlyBaseRent" id="btai_OperatingLeaseMonthlyBaseRent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PlacementAgentCompensationNumberOfShares" id="btai_PlacementAgentCompensationNumberOfShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="InsuranceCoveragePercentageOfSettlementAmount" id="btai_InsuranceCoveragePercentageOfSettlementAmount" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDebtAmendment" id="btai_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDebtAmendment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DeferredTaxLiabilitiesInsuranceSettlement" id="btai_DeferredTaxLiabilitiesInsuranceSettlement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DebtInstrumentFinancialCovenantChangeInMinimumLiquidityRequirement" id="btai_DebtInstrumentFinancialCovenantChangeInMinimumLiquidityRequirement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="NinthAmendmentOptionMember" id="btai_NinthAmendmentOptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NinthAmendmentOptionBMember" id="btai_NinthAmendmentOptionBMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RequiredPrincipalPrepaymentOfProceedsFromIssuanceOfWarrantsPercent" id="btai_RequiredPrincipalPrepaymentOfProceedsFromIssuanceOfWarrantsPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PrepaymentOfFiftyPercentOfProceedsNotRequiredMember" id="btai_PrepaymentOfFiftyPercentOfProceedsNotRequiredMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromCapitalRaiseActivities" id="btai_ProceedsFromCapitalRaiseActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ProceedsFromCapitalRaisePrepayments" id="btai_ProceedsFromCapitalRaisePrepayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
</xsd:schema>
