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  <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" />
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  <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" />
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  <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" />
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</xsd:schema>
