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  <xs:element id="cmps_AmericanDepositarySharesMember" abstract="true" name="AmericanDepositarySharesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_AtTheMarketOfferingMember" abstract="true" name="AtTheMarketOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_UnderwrittenOfferingMember" abstract="true" name="UnderwrittenOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_LoanAgreementMember" abstract="true" name="LoanAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_LoanAgreementTermLoanOneMember" abstract="true" name="LoanAgreementTermLoanOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_AmendedLoanAgreementMember" abstract="true" name="AmendedLoanAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_PIPEWarrantsMember" abstract="true" name="PIPEWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_A2025ADSWarrantsMember" abstract="true" name="A2025ADSWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_A2026ADSWarrantsMember" abstract="true" name="A2026ADSWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_SaleOfStockMaximumAmountAllowableForSale" abstract="false" name="SaleOfStockMaximumAmountAllowableForSale" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_NumberOfOrdinarySharesConversionRatio" abstract="false" name="NumberOfOrdinarySharesConversionRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="cmps_SaleOfStockAmountAuthorized" abstract="false" name="SaleOfStockAmountAuthorized" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_DebtInstrumentNumberOfTranches" abstract="false" name="DebtInstrumentNumberOfTranches" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="cmps_ProceedsFromWarrantExercisesFullyExercised" abstract="false" name="ProceedsFromWarrantExercisesFullyExercised" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_ResearchAndDevelopmentTaxCreditCurrent" abstract="false" name="ResearchAndDevelopmentTaxCreditCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_PrepaidExpenseResearchAndDevelopmentCurrent" abstract="false" name="PrepaidExpenseResearchAndDevelopmentCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_ResearchAndDevelopmentTaxCreditPotentialReceivable" abstract="false" name="ResearchAndDevelopmentTaxCreditPotentialReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_AmendedLoanAgreementTermLoanOneMember" abstract="true" name="AmendedLoanAgreementTermLoanOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_FacilityFeesMember" abstract="true" name="FacilityFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_CompanyFeesMember" abstract="true" name="CompanyFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_WarrantFeesMember" abstract="true" name="WarrantFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_EndOfTermChargeMember" abstract="true" name="EndOfTermChargeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_DebtInstrumentMinimumDrawingsAmount" abstract="false" name="DebtInstrumentMinimumDrawingsAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_OptionsNumberOfSharesAvailableForPurchasePercentOfPrincipalAmountOfTermLoanAdvances" abstract="false" name="OptionsNumberOfSharesAvailableForPurchasePercentOfPrincipalAmountOfTermLoanAdvances" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="cmps_OptionsExercisableNumber" abstract="false" name="OptionsExercisableNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="cmps_OptionsExercisableFairValue" abstract="false" name="OptionsExercisableFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_DebtInstrumentCovenantMinimumCashOnHandPercent" abstract="false" name="DebtInstrumentCovenantMinimumCashOnHandPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cmps_DebtInstrumentMarketCapitalization" abstract="false" name="DebtInstrumentMarketCapitalization" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_LongTermDebtEndOfTermCharge" abstract="false" name="LongTermDebtEndOfTermCharge" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_LongTermDebtIncludingEndOfTermCharge" abstract="false" name="LongTermDebtIncludingEndOfTermCharge" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_DebtInstrumentPaidInKindInterestPayable" abstract="false" name="DebtInstrumentPaidInKindInterestPayable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_FairValueIssuanceOfWarrants" abstract="false" name="FairValueIssuanceOfWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_FairValueConversionOfWarrants" abstract="false" name="FairValueConversionOfWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_HerculesCapitalInc.Member" abstract="true" name="HerculesCapitalInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_ClassOfWarrantOrRightThresholdConsecutiveTradingDays" abstract="false" name="ClassOfWarrantOrRightThresholdConsecutiveTradingDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="cmps_ProceedsFromIssuanceAndExercisesOfWarrants" abstract="false" name="ProceedsFromIssuanceAndExercisesOfWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_A2017EquityIncentivePlanMember" abstract="true" name="A2017EquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_ShareBasedCompensationArrangementByShareBasedPaymentAwardAllowableIncreaseInSharesAuthorizedForIssuancePercentageOfOutstandingStockMaximum" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAllowableIncreaseInSharesAuthorizedForIssuancePercentageOfOutstandingStockMaximum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cmps_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumIncreaseInSharesAvailableForIssuance" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumIncreaseInSharesAvailableForIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="cmps_A2020ShareOptionPlanMember" abstract="true" name="A2020ShareOptionPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumPercentageOfSharesOutstandingNumberOfSharesReservedForIssuanceMayIncrease" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumPercentageOfSharesOutstandingNumberOfSharesReservedForIssuanceMayIncrease" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="cmps_A2022InducementGrantOptionAwardMember" abstract="true" name="A2022InducementGrantOptionAwardMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_A2026InducementPlanMember" abstract="true" name="A2026InducementPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_ChangeInFairValueOfWarrantLiabilitiesForDilutiveSecurities" abstract="false" name="ChangeInFairValueOfWarrantLiabilitiesForDilutiveSecurities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmps_EmployeeSharePurchasePlanMember" abstract="true" name="EmployeeSharePurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_UnvestedRestrictedShareUnitsMember" abstract="true" name="UnvestedRestrictedShareUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_ShareOptionsMember" abstract="true" name="ShareOptionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_EquityWarrantsMember" abstract="true" name="EquityWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_LiabilityWarrantsMember" abstract="true" name="LiabilityWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_NumberOfReportableSegmentsNotDisclosedFlag" abstract="false" name="NumberOfReportableSegmentsNotDisclosedFlag" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:booleanItemType"/>
  <xs:element id="cmps_DevelopmentExpensesMember" abstract="true" name="DevelopmentExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_PersonnelExpensesMember" abstract="true" name="PersonnelExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_NonCashShareBasedCompensationExpenseMember" abstract="true" name="NonCashShareBasedCompensationExpenseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_OtherExpensesMember" abstract="true" name="OtherExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_LegalAndProfessionalFeesMember" abstract="true" name="LegalAndProfessionalFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_FacilitiesAndOtherExpensesMember" abstract="true" name="FacilitiesAndOtherExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmps_SingleOperatingSegmentMember" abstract="true" name="SingleOperatingSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
