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  <xsd:element name="PaidInKindInterestForRoyaltyFinancingObligation" id="mist_PaidInKindInterestForRoyaltyFinancingObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AccruedLiabilitiesDisclosureTextBlock" id="mist_AccruedLiabilitiesDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfRoyaltyFinancingObligationTableTextBlock" id="mist_ScheduleOfRoyaltyFinancingObligationTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RoyaltyFinancingObligationRollForward" id="mist_RoyaltyFinancingObligationRollForward" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RoyaltyFinancingObligationSettledWithoutCash" id="mist_RoyaltyFinancingObligationSettledWithoutCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RoyaltyFinancingObligationRoyaltyPaidAndPayable" id="mist_RoyaltyFinancingObligationRoyaltyPaidAndPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RoyaltyFinancingObligationEffectiveInterestRate" id="mist_RoyaltyFinancingObligationEffectiveInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="SalesAgentCommissionPercent" id="mist_SalesAgentCommissionPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
</xsd:schema>
