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<!--Created on: 11/12/2020 9:01:00 AM-->
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  <element id="btai_ProceedsFromIssuanceOfCommonStockGross" name="ProceedsFromIssuanceOfCommonStockGross" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_LumpSumPayableUponMilestonesMember" name="LumpSumPayableUponMilestonesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_LumpSumPaymentWithinSixtyDaysAfterCumulativeNetSalesMember" name="LumpSumPaymentWithinSixtyDaysAfterCumulativeNetSalesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_MaximumThresholdPeriodForPayment" name="MaximumThresholdPeriodForPayment" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_TermOfAgreement" name="TermOfAgreement" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_DevelopmentMilestonesMember" name="DevelopmentMilestonesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_SalesMilestonesMember" name="SalesMilestonesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_CollaborativeArrangementMilestonePaymentsPotential" name="CollaborativeArrangementMilestonePaymentsPotential" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_BioxcelCorporationMember" name="BioxcelCorporationMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_LesseeOperatingLeaseNumberOfRenewal" name="LesseeOperatingLeaseNumberOfRenewal" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_LesseeOperatingLeaseRenewalAtPercentageOfMarketRates" name="LesseeOperatingLeaseRenewalAtPercentageOfMarketRates" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_CollaborativeArrangementMilestonePotentialPercent" name="CollaborativeArrangementMilestonePotentialPercent" nillable="true" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_PatentCostsPolicyTextBlock" name="PatentCostsPolicyTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_AssetContributionAgreementMember" name="AssetContributionAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_JefferiesMember" name="JefferiesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_SeparationAndSharedServicesAgreementMember" name="SeparationAndSharedServicesAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_ExpensesAccruedUnderContractualArrangementsWithClinicalResearchOrganizationsPolicyPolicyTextBlock" name="ExpensesAccruedUnderContractualArrangementsWithClinicalResearchOrganizationsPolicyPolicyTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_IncentiveAwardPlan2020Member" name="IncentiveAwardPlan2020Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfIncreaseInCommonStockAvailableForGrant" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfIncreaseInCommonStockAvailableForGrant" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_EmployeeStockPurchasePlan2020Member" name="EmployeeStockPurchasePlan2020Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_EmployeeStockPurchasePlanMaximumNumberOfSharesIssuedOrTransferred" name="EmployeeStockPurchasePlanMaximumNumberOfSharesIssuedOrTransferred" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_PaycheckProtectionProgramCaresActMember" name="PaycheckProtectionProgramCaresActMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_StockPlan2017Member" name="StockPlan2017Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_AccruedResearchAndDevelopmentExpenses" name="AccruedResearchAndDevelopmentExpenses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_OpearatingLeaseRightOfUseAssetAndLiabilityNonCashAdoption" name="OpearatingLeaseRightOfUseAssetAndLiabilityNonCashAdoption" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_UnderwritersOptionExercisablePeriod" name="UnderwritersOptionExercisablePeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_AreaOfAdditionSpaceLeased" name="AreaOfAdditionSpaceLeased" nillable="true" type="num:areaItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_PayableUponLaterTwelveMonthAnniversaryOfOfferingAndFirstDosingForBxcl701ProgramMember" name="PayableUponLaterTwelveMonthAnniversaryOfOfferingAndFirstDosingForBxcl701ProgramMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_NumberOfSharesAvailableForPurchase" name="NumberOfSharesAvailableForPurchase" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsFairValueOfGrantsPerShare" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsFairValueOfGrantsPerShare" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="btai_GrantDateFairValue" name="GrantDateFairValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
