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  <xs:element id="coll_MarketableSecuritiesMember" abstract="true" name="MarketableSecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_SaleOfMarketableSecurities" abstract="false" name="SaleOfMarketableSecurities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_InventoryCurrentAndNoncurrent" abstract="false" name="InventoryCurrentAndNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_PrepaidSavingsVouchers" abstract="false" name="PrepaidSavingsVouchers" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_PrepaidRegulatoryFeesCurrent" abstract="false" name="PrepaidRegulatoryFeesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DeferredDebtDiscountsAndIssuanceCostsNoncurrent" abstract="false" name="DeferredDebtDiscountsAndIssuanceCostsNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_NucyntaMember" abstract="true" name="NucyntaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_AccruedProductTaxesAndFeesCurrent" abstract="false" name="AccruedProductTaxesAndFeesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_AccruedIncentiveCompensationCurrent" abstract="false" name="AccruedIncentiveCompensationCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_AccruedPayablesForInventoryCurrent" abstract="false" name="AccruedPayablesForInventoryCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_AccruedLiabilityForCashSettledShareBasedAwardsAssumedFromAcquireeCurrent" abstract="false" name="AccruedLiabilityForCashSettledShareBasedAwardsAssumedFromAcquireeCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_AccruedSeveranceExpenseRelatedToAcquisitionCurrent" abstract="false" name="AccruedSeveranceExpenseRelatedToAcquisitionCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_PurduePharmaLimitedPartnershipPatentInfringementMember" abstract="true" name="PurduePharmaLimitedPartnershipPatentInfringementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_PurduePharmaLimitedPartnershipPatentInfringementDistrictOfMassachusettsMember" abstract="true" name="PurduePharmaLimitedPartnershipPatentInfringementDistrictOfMassachusettsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_AquestiveTherapeuticsIncLitigationMember" abstract="true" name="AquestiveTherapeuticsIncLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_GrunenthalGMBGLitigationMember" abstract="true" name="GrunenthalGMBGLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_BdsiAcquisitionLitigationMember" abstract="true" name="BdsiAcquisitionLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_ArbitrationWithNorthSoundPharmaceuticalsIncMember" abstract="true" name="ArbitrationWithNorthSoundPharmaceuticalsIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_WalgreenCo.LawsuitMember" abstract="true" name="WalgreenCo.LawsuitMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_LossContingencyStayPeriodBeforeFinalFederalDrugAdministrationApprovalCanBeIssuedIfPatentInfringementLitigationElected" abstract="false" name="LossContingencyStayPeriodBeforeFinalFederalDrugAdministrationApprovalCanBeIssuedIfPatentInfringementLitigationElected" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="coll_StatutoryPeriodOfProceedings" abstract="false" name="StatutoryPeriodOfProceedings" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="coll_LossContingencyNumberOfAdditionalCasesFiled" abstract="false" name="LossContingencyNumberOfAdditionalCasesFiled" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="coll_LossContingencyNumberOfDemandLettersReceivedFromPurportedStockholders" abstract="false" name="LossContingencyNumberOfDemandLettersReceivedFromPurportedStockholders" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="coll_A2022TermLoanMember" abstract="true" name="A2022TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_TermLoan2024Member" abstract="true" name="TermLoan2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_A2025CreditAgreementMember" abstract="true" name="A2025CreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_DebtModificationAndTransactionFee" abstract="false" name="DebtModificationAndTransactionFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtInstrumentCommitmentAndOtherFees" abstract="false" name="DebtInstrumentCommitmentAndOtherFees" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtInstrumentEarlyMaturityThresholdConvertibleNotesOutstandingPrincipalBalance" abstract="false" name="DebtInstrumentEarlyMaturityThresholdConvertibleNotesOutstandingPrincipalBalance" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtInstrumentEarlyMaturityThresholdLiquidity" abstract="false" name="DebtInstrumentEarlyMaturityThresholdLiquidity" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtDiscountAndIssuanceCostsIncurredAndIncludedInExtinguishmentOfDebt" abstract="false" name="DebtDiscountAndIssuanceCostsIncurredAndIncludedInExtinguishmentOfDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtInstrumentFinancialCovenantCashNettingLimit" abstract="false" name="DebtInstrumentFinancialCovenantCashNettingLimit" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtInstrumentCostOfRedemption" abstract="false" name="DebtInstrumentCostOfRedemption" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtInstrumentConvertibleConsecutiveBusinessDays" abstract="false" name="DebtInstrumentConvertibleConsecutiveBusinessDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="coll_DebtInstrumentConvertibleMeasurementPeriod" abstract="false" name="DebtInstrumentConvertibleMeasurementPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="coll_DebtInstrumentConvertibleThresholdPercentageOfProductOfSalePriceOfCommonStockAndConversionRate" abstract="false" name="DebtInstrumentConvertibleThresholdPercentageOfProductOfSalePriceOfCommonStockAndConversionRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_DebtInstrumentDefaultPeriodOnPaymentOfInterest" abstract="false" name="DebtInstrumentDefaultPeriodOnPaymentOfInterest" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="coll_DebtInstrumentDefaultProvisionTermOfNoticeToCompanyToSureDefault" abstract="false" name="DebtInstrumentDefaultProvisionTermOfNoticeToCompanyToSureDefault" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="coll_DebtInstrumentDefaultProvisionsThresholdAmountBorrowed" abstract="false" name="DebtInstrumentDefaultProvisionsThresholdAmountBorrowed" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtInstrumentDefaultProvisionsThresholdAmountOfPayment" abstract="false" name="DebtInstrumentDefaultProvisionsThresholdAmountOfPayment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_ContractualInterestExpense" abstract="false" name="ContractualInterestExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DebtInstrumentTotalMinimumPayments" abstract="false" name="DebtInstrumentTotalMinimumPayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DeferredRoyaltyLiabilityTable" abstract="true" name="DeferredRoyaltyLiabilityTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="coll_NetSalesPriorToJuly12025Member" abstract="true" name="NetSalesPriorToJuly12025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_NetSalesPriorAfterJuly12025AndUpToMarch2032Member" abstract="true" name="NetSalesPriorAfterJuly12025AndUpToMarch2032Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_DeferredRoyaltyLiabilityLineItems" abstract="true" name="DeferredRoyaltyLiabilityLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="coll_RoyaltyRatePercent" abstract="false" name="RoyaltyRatePercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_DeferredRoyaltyObligationInterestRateEffectivePercentage" abstract="false" name="DeferredRoyaltyObligationInterestRateEffectivePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_InterestExpenseOnDeferredRoyaltyLiability" abstract="false" name="InterestExpenseOnDeferredRoyaltyLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_PaymentOfDeferredRoyaltyObligation" abstract="false" name="PaymentOfDeferredRoyaltyObligation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DeferredRoyaltyAcquiredRollForward" abstract="true" name="DeferredRoyaltyAcquiredRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="coll_DeferredRoyaltyLiabilityAccretionsNet" abstract="false" name="DeferredRoyaltyLiabilityAccretionsNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_StoughtonMassachusettsMember" abstract="true" name="StoughtonMassachusettsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_DurhamNorthCarolinaMember" abstract="true" name="DurhamNorthCarolinaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_OperatingLeaseArrangementForVehiclesMember" abstract="true" name="OperatingLeaseArrangementForVehiclesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_NumberOfRenewalPeriodsOperatingLease" abstract="false" name="NumberOfRenewalPeriodsOperatingLease" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="coll_OperatingLeaseAnnualBaseRent" abstract="false" name="OperatingLeaseAnnualBaseRent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_OperatingLeaseAnnualBaseRentIncreasePercentage" abstract="false" name="OperatingLeaseAnnualBaseRentIncreasePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_ShareRepurchaseProgram2023Member" abstract="true" name="ShareRepurchaseProgram2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_AcceleratedShareRepurchaseProgramJuly2023Member" abstract="true" name="AcceleratedShareRepurchaseProgramJuly2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_AcceleratedShareRepurchaseProgramNovember2023Member" abstract="true" name="AcceleratedShareRepurchaseProgramNovember2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_ShareRepurchaseProgram202425Member" abstract="true" name="ShareRepurchaseProgram202425Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_AcceleratedShareRepurchaseProgramMay2024Member" abstract="true" name="AcceleratedShareRepurchaseProgramMay2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_AcceleratedShareRepurchaseProgramMay2025Member" abstract="true" name="AcceleratedShareRepurchaseProgramMay2025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_ShareRepurchaseProgram202526Member" abstract="true" name="ShareRepurchaseProgram202526Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_StockIncentivePlan2014Member" abstract="true" name="StockIncentivePlan2014Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_EquityIncentivePlan2025Member" abstract="true" name="EquityIncentivePlan2025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_AwardsGrantedPriorTo2024Member" abstract="true" name="AwardsGrantedPriorTo2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_AwardsGrantedAfter2024Member" abstract="true" name="AwardsGrantedAfter2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualAdditionalSharesAuthorizedAsPercentageOfOutstandingShares" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualAdditionalSharesAuthorizedAsPercentageOfOutstandingShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExercisePeriodAfterExpirationDate" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExercisePeriodAfterExpirationDate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="coll_PaymentsForRepurchaseOfCommonStockUpfrontPaymentPercent" abstract="false" name="PaymentsForRepurchaseOfCommonStockUpfrontPaymentPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_StockRepurchasePricePerShare" abstract="false" name="StockRepurchasePricePerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="coll_TreasuryStockSharesAdditionalReceived" abstract="false" name="TreasuryStockSharesAdditionalReceived" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="coll_TreasuryStockAcquiredFeesAndCommissionIncurred" abstract="false" name="TreasuryStockAcquiredFeesAndCommissionIncurred" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardCumulativePerformancePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardCumulativePerformancePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardAverageStockPricePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAverageStockPricePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="coll_EquityInstrumentsOtherThanOptionsGrantsInPeriodWithMarketBasedVestingConditionsWeightedAverageGrantDateFairValue" abstract="false" name="EquityInstrumentsOtherThanOptionsGrantsInPeriodWithMarketBasedVestingConditionsWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="coll_EmployeeStockPurchasePlanPurchasePricePercentage" abstract="false" name="EmployeeStockPurchasePlanPurchasePricePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_EmployeeStockPurchasePlanCompensationExpense" abstract="false" name="EmployeeStockPurchasePlanCompensationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustment" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustment" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedPerformanceAdjustmentsWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedPerformanceAdjustmentsWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="coll_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensationAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensationAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensationPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDebtExtinguishment" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDebtExtinguishment" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_EffectiveIncomeTaxRateReconciliationChangeInTaxRatesAndOtherPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationChangeInTaxRatesAndOtherPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="coll_DeferredTaxAssetsOperatingLeaseLiabilities" abstract="false" name="DeferredTaxAssetsOperatingLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DeferredTaxAssetsCapitalizedResearchAndDevelopment" abstract="false" name="DeferredTaxAssetsCapitalizedResearchAndDevelopment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DeferredTaxAssetRoyaltyObligation" abstract="false" name="DeferredTaxAssetRoyaltyObligation" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DeferredTaxLiabilitiesDebtDiscount" abstract="false" name="DeferredTaxLiabilitiesDebtDiscount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DeferredTaxLiabilitiesOperatingLeaseAssets" abstract="false" name="DeferredTaxLiabilitiesOperatingLeaseAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_BiodeliverySciencesInternationalIncMember" abstract="true" name="BiodeliverySciencesInternationalIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_IncomeTaxExpenseBenefitDueToChangeInDeferredTaxAssetsValuationAllowance" abstract="false" name="IncomeTaxExpenseBenefitDueToChangeInDeferredTaxAssetsValuationAllowance" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_OperatingLossCarryforwardsSubjectToExpiration" abstract="false" name="OperatingLossCarryforwardsSubjectToExpiration" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_OperatingLossCarryforwardsNotSubjectToExpiration" abstract="false" name="OperatingLossCarryforwardsNotSubjectToExpiration" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_NetOperatingLossAcquiredInBusinessCombination" abstract="false" name="NetOperatingLossAcquiredInBusinessCombination" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_OperatingLossCarryforwardsSubjectsToLimitationsOnUse" abstract="false" name="OperatingLossCarryforwardsSubjectsToLimitationsOnUse" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_AmortizationAndImpairmentOfIntangibleAssets" abstract="false" name="AmortizationAndImpairmentOfIntangibleAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_SingleReportableSegmentMember" abstract="true" name="SingleReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_CommercialExpenses" abstract="false" name="CommercialExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_CorporateExpenses" abstract="false" name="CorporateExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_MedicalExpenses" abstract="false" name="MedicalExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_TechnicalOperationsExpenses" abstract="false" name="TechnicalOperationsExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="coll_DavidDieterMember" abstract="true" name="DavidDieterMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="coll_ColleenTupperMember" abstract="true" name="ColleenTupperMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
