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  <element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageGrantDateFairValueOutstanding" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageGrantDateFairValueOutstanding" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingWeightedAverageFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingWeightedAverageFairValue" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AccruedRebatesReturnsAndDiscountsCurrent" name="AccruedRebatesReturnsAndDiscountsCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_StockVestedDuringPeriodSharesRestrictedStockUnits" name="StockVestedDuringPeriodSharesRestrictedStockUnits" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_IncreaseDecreaseInAccruedRebatesReturnsAndDiscounts" name="IncreaseDecreaseInAccruedRebatesReturnsAndDiscounts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AllowanceForRebatesAndIncentivesMember" name="AllowanceForRebatesAndIncentivesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AllowanceAndChargebacksForTradeReceivablesMember" name="AllowanceAndChargebacksForTradeReceivablesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_NewTermLoanFacilityMember" name="NewTermLoanFacilityMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_SiliconValleyBankLoanAgreementConsentAndSixthAmendmentMember" name="SiliconValleyBankLoanAgreementConsentAndSixthAmendmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_PriorToFirstAnniversaryMember" name="PriorToFirstAnniversaryMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_BetweenFirstAnniversaryAndSecondAnniversaryMember" name="BetweenFirstAnniversaryAndSecondAnniversaryMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_FollowingSecondAnniversaryMember" name="FollowingSecondAnniversaryMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CollaborativeArrangementRoyaltyPaymentAsPercentageOfAnnualNetSales" name="CollaborativeArrangementRoyaltyPaymentAsPercentageOfAnnualNetSales" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_ThresholdLimitOfEbitdaToRepayPrincipalAndAccruedInterestPriorToSpecificDate" name="ThresholdLimitOfEbitdaToRepayPrincipalAndAccruedInterestPriorToSpecificDate" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_DebtInstrumentPrepaymentFeePercent" name="DebtInstrumentPrepaymentFeePercent" nillable="true" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_DebtInstrumentCovenantLiquidityRatio" name="DebtInstrumentCovenantLiquidityRatio" nillable="true" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_DebtDefaultInterestRate" name="DebtDefaultInterestRate" nillable="true" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_ShareBasedCompensationArrangementByShareBasedPaymentAwardRemainingFromEarlyExerciseOfStockOptions" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardRemainingFromEarlyExerciseOfStockOptions" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CustomerOneMember" name="CustomerOneMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CustomerTwoMember" name="CustomerTwoMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CustomerThreeMember" name="CustomerThreeMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_StockIssuanceCosts" name="StockIssuanceCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_NumberOfPatentsListedInFdaOrangeBook" name="NumberOfPatentsListedInFdaOrangeBook" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_TevaLitigationMember" name="TevaLitigationMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CollaborativeArrangementTerminationFee" name="CollaborativeArrangementTerminationFee" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_ContractWithCustomerRefundLiabilityMember" name="ContractWithCustomerRefundLiabilityMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_ContractWithCustomerLiabilityProvisionForCurrentPeriodSales" name="ContractWithCustomerLiabilityProvisionForCurrentPeriodSales" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_ContractWithCustomerLiabilityChangeInEstimateOfPriorPeriodSales" name="ContractWithCustomerLiabilityChangeInEstimateOfPriorPeriodSales" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_ContractWithCustomerLiabilityDecreaseDueToCreditsAndPayments" name="ContractWithCustomerLiabilityDecreaseDueToCreditsAndPayments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_XtampzaMember" name="XtampzaMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_NucyntaMember" name="NucyntaMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_NumberOfRenewalPeriodsOperatingLease" name="NumberOfRenewalPeriodsOperatingLease" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_OperatingLeaseAnnualInitialBaseRentPerSquareFoot" name="OperatingLeaseAnnualInitialBaseRentPerSquareFoot" nillable="true" type="us-types:perUnitItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_OperatingLeaseAnnualBaseRentIncreasePercentage" name="OperatingLeaseAnnualBaseRentIncreasePercentage" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_UpfrontCashPaidForAssetAcquisition" name="UpfrontCashPaidForAssetAcquisition" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquiredRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAbstract" name="AssetAcquiredRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssets" name="AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssets" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" name="AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPrepaidExpenses" name="AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPrepaidExpenses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" name="AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_MinimumAnnualRoyaltyPaymentsLiability" name="MinimumAnnualRoyaltyPaymentsLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_MinimumQuarterlyRoyaltyPaymentsLiability" name="MinimumQuarterlyRoyaltyPaymentsLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_MinimumRoyaltyPaymentLiability" name="MinimumRoyaltyPaymentLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_RoyaltyPayableFairValue" name="RoyaltyPayableFairValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_DiscountedCashFlowRate" name="DiscountedCashFlowRate" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_InterestExpenseRoyalty" name="InterestExpenseRoyalty" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_RoyaltyPayableRemainderOfFiscalYear" name="RoyaltyPayableRemainderOfFiscalYear" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_RoyaltyPayableYearTwo" name="RoyaltyPayableYearTwo" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_RoyaltyPayableYearThree" name="RoyaltyPayableYearThree" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_RoyaltyPayableYearFour" name="RoyaltyPayableYearFour" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_RoyaltyPaymentDue" name="RoyaltyPaymentDue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_UpfrontCashPaid" name="UpfrontCashPaid" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AccruedCostOfProductRevenues" name="AccruedCostOfProductRevenues" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AccruedInventoryCurrent" name="AccruedInventoryCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_OnsolisMember" name="OnsolisMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssumedLiabilityRelatedToProductSales" name="AssumedLiabilityRelatedToProductSales" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_ThirdAmendmentToCommercializationAgreementMember" name="ThirdAmendmentToCommercializationAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssertioMember" name="AssertioMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_SalesRoyaltyStructure1Member" name="SalesRoyaltyStructure1Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_SalesRoyaltyStructure2Member" name="SalesRoyaltyStructure2Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_SalesRoyaltyStructure3Member" name="SalesRoyaltyStructure3Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_SalesRoyaltyStructure4Member" name="SalesRoyaltyStructure4Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_SalesRoyaltyStructure5Member" name="SalesRoyaltyStructure5Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CollaborativeArrangementRoyaltyPaymentLimit" name="CollaborativeArrangementRoyaltyPaymentLimit" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CollaborativeArrangementMinimumRoyaltyPaymentEliminated" name="CollaborativeArrangementMinimumRoyaltyPaymentEliminated" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CollaborativeArrangementSupplementalRoyaltyPaymentBasedOnNetSales" name="CollaborativeArrangementSupplementalRoyaltyPaymentBasedOnNetSales" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_NetSalesThresholdUponWhichCounterpartyCanTerminateWithoutPenalty" name="NetSalesThresholdUponWhichCounterpartyCanTerminateWithoutPenalty" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CommencementScenario1Member" name="CommencementScenario1Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CommencementScenario2Member" name="CommencementScenario2Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_IssuanceCostsFromIssuanceOfCommonStock" name="IssuanceCostsFromIssuanceOfCommonStock" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_LicenseAgreementsAbstract" name="LicenseAgreementsAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_LicenseAgreementsTextBlock" name="LicenseAgreementsTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_InterestExpenseRecognizedRelatingToRoyaltyPaymentsPriorToThirdAmendment" name="InterestExpenseRecognizedRelatingToRoyaltyPaymentsPriorToThirdAmendment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquiredCostsAccumulated" name="AssetAcquiredCostsAccumulated" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AmortizationExpenseRecognizedPriorToThirdAmendment" name="AmortizationExpenseRecognizedPriorToThirdAmendment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionCostsAccumulatedRebatesIncentivesTradeAllowancesAndChargebacksAssumed" name="AssetAcquisitionCostsAccumulatedRebatesIncentivesTradeAllowancesAndChargebacksAssumed" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionCostsAccumulatedWarrantIssued" name="AssetAcquisitionCostsAccumulatedWarrantIssued" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionCostsAccumulatedTotal" name="AssetAcquisitionCostsAccumulatedTotal" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AdjustmentDueToRemeasurementOfLiability" name="AdjustmentDueToRemeasurementOfLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AdditionalCostsIncurred" name="AdditionalCostsIncurred" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionCostsAccumulatedTransactionCosts" name="AssetAcquisitionCostsAccumulatedTransactionCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionCostsAccumulatedRebatesAndIncentives" name="AssetAcquisitionCostsAccumulatedRebatesAndIncentives" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_AssetAcquisitionCostsAccumulatedTradeAllowancesAndChargebacksAssumed" name="AssetAcquisitionCostsAccumulatedTradeAllowancesAndChargebacksAssumed" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_PaymentForInventory" name="PaymentForInventory" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_PaymentOfReimbursementForPrepaidExpenses" name="PaymentOfReimbursementForPrepaidExpenses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_NucyntaCommercializationAgreementMember" name="NucyntaCommercializationAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_SalesRoyaltyStructure6Member" name="SalesRoyaltyStructure6Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CollaborativeArrangementPercentageOfSupplementalRoyaltyPaymentBasedOnNetSales" name="CollaborativeArrangementPercentageOfSupplementalRoyaltyPaymentBasedOnNetSales" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_BiodeliverySciencesInternationalInc.Member" name="BiodeliverySciencesInternationalInc.Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_OnsolisIntangibleAssetMember" name="OnsolisIntangibleAssetMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_MilestonePayableAmount" name="MilestonePayableAmount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CollaborativeArrangementRoyaltyPaymentAsPercentageOfAnnualNetSalesAfterSpecificPeriod" name="CollaborativeArrangementRoyaltyPaymentAsPercentageOfAnnualNetSalesAfterSpecificPeriod" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CollaborativeArrangementRoyaltyPaymentLimitAfterSpecificPeriod" name="CollaborativeArrangementRoyaltyPaymentLimitAfterSpecificPeriod" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_WarrantIssued" name="WarrantIssued" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_NumberOfLawsuitsFiled" name="NumberOfLawsuitsFiled" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_StoughtonMassachusettsMember" name="StoughtonMassachusettsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_CantonMassachusettsMember" name="CantonMassachusettsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_UnrecognizedTaxBenefitsIncreaseResultingFromIrsExamination" name="UnrecognizedTaxBenefitsIncreaseResultingFromIrsExamination" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_UnrecognizedTaxBenefitsIncreaseResultingFromChangeInTaxRate" name="UnrecognizedTaxBenefitsIncreaseResultingFromChangeInTaxRate" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_NetOperatingLossCarryforwardsIncreaseDecrease" name="NetOperatingLossCarryforwardsIncreaseDecrease" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_SummaryOfCostsIncludedInAcquiredAsset" name="SummaryOfCostsIncludedInAcquiredAsset" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="coll_LicenseAgreementsLineItems" name="LicenseAgreementsLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
