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  <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="Warrants2024PreFundedWarrantsMember" id="btai_Warrants2024PreFundedWarrantsMember" 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="RestrictedStockUnitsVesting100PercentAtOneYearAnniversaryMember" id="btai_RestrictedStockUnitsVesting100PercentAtOneYearAnniversaryMember" 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="NumberOfWarrantsExercised" id="btai_NumberOfWarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
</xsd:schema>
