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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Incorporation, State or Country Code</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedGrossToNetRevenueLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued gross-to-net revenue liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedGrossToNetRevenueLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued gross to net revenue liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedGrossToNetRevenueLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued gross-to-net revenue liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net of tax impact</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">INVESTMENTS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredInProcessResearchAndDevelopment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquired in-process research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredInProcessResearchAndDevelopment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Acquired in process research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredInProcessResearchAndDevelopment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Acquired In Process Research And Development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SEGMENT INFORMATION</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding Reconciliation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Number of Shares Outstanding Reconciliation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_StockholdersEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stockholders' equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_StockholdersEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders Equity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_StockholdersEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' Equity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Arrangement, Contract to Perform for Others, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NumberOfTradingDaysFromReceiptOfTheNoticeLetter_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of trading days from receipt of the notice letter.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NumberOfTradingDaysFromReceiptOfTheNoticeLetter_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Trading Days From Receipt Of The Notice Letter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NumberOfTradingDaysFromReceiptOfTheNoticeLetter_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of trading days from receipt of the notice letter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-of-Use Asset Obtained in Exchange for Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other &#8211; non-current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_DueFromCollaborativeAndLicencingArrangements_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of asset related to consideration paid in advance for pre-commercialization fees that provide economic benefits with a future period of one year or the normal operating cycle, if longer.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_DueFromCollaborativeAndLicencingArrangements_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Due From Collaborative And Licencing Arrangements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_DueFromCollaborativeAndLicencingArrangements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Due from collaborative and licensing arrangements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PriorPeriodReclassificationAdjustmentDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reclassification, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PriorPeriodReclassificationAdjustmentDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RECLASSIFICATIONS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities and stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payables and Accruals [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ProductRevenueAcquisitionDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acqusition date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ProductRevenueAcquisitionDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenue Acquisition Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ProductRevenueAcquisitionDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenue acquisition date.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryWriteDownExpectedToBeReimbursed_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Write Down Expected To Be Reimbursed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryWriteDownExpectedToBeReimbursed_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Inventory write down expected to be reimbursed.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryWriteDownExpectedToBeReimbursed_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory unsalable product</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreSevenHundredAndFiftyMillionAndLessThanOneBillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more seven hundred and fifty million and less than one billion member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreSevenHundredAndFiftyMillionAndLessThanOneBillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Seven Hundred And Fifty Million And Less Than One Billion [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreSevenHundredAndFiftyMillionAndLessThanOneBillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty More Seven Hundred And Fifty Million And Less Than One Billion [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseOptionToTerminate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Option to Terminate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseOptionToTerminate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee, Operating Lease, Option to Terminate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Remaining Amortization Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets, Remaining Amortization Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PurchasePriceConsiderationForIntangibleAssetsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Purchase price consideration for intangible assets acquired.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PurchasePriceConsiderationForIntangibleAssetsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase Price Consideration For Intangible Assets Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PurchasePriceConsiderationForIntangibleAssetsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and acquired intangibles</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PurchasePriceConsiderationForIntangibleAssetsAcquired_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">License and acquired intangibles for AGAMREE (IPR&amp;D)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective Income Tax Rate Reconciliation, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid for income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Taxes Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Authority [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Authority [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment in connection with asset acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License Agreement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License Agreement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Inventory, Current [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of current inventory, net</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccretionOfDiscount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accretion of discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPurchasePriceConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition purchase price consideration.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPurchasePriceConsideration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset acquisition purchase price consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFVNINoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Securities, FV-NI, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFVNINoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment in equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFVNINoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-lived intangible asset, useful life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ShareRepurchaseProgramAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock unit granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Disaggregated Product Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of options, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License Agreement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License Agreement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementWithBioMarinMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License agreement with BioMarin.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementWithBioMarinMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement With Bio Marin [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementWithBioMarinMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License Agreement with BioMarin [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to reconcile net income to net cash provided by (used in) operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The entire disclosure for the carrying amount as of the balance sheet date of expenditures made in advance of the timing of recognition of expenses which are expected to be charged against earnings within one year or the normal operating cycle, if longer. Includes, but is not limited to, prepaid research, prepaid product development activities and prepaid insurance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expenses And Other Current Assets [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid Expenses and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Finished Goods, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finished goods</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ShareRepurchaseProgramDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' equity:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPercentageOfOutstandingOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition percentage of outstanding ordinary shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPercentageOfOutstandingOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Percentage Of Outstanding Ordinary Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPercentageOfOutstandingOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Acquisition Percentage Of Outstanding Ordinary Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPercentageOfOutstandingOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Asset acquisition percentage of outstanding ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retained earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature of Operations [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Organization and Description of Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireEquitySecuritiesFvNi_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Equity Securities, FV-NI</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireEquitySecuritiesFvNi_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchase of equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborationAgreementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborationAgreementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration Agreement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MinimumRoyalty_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum royalty.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MinimumRoyalty_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Royalty</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MinimumRoyalty_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum royalty</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Organization, Consolidation and Presentation of Financial Statements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number Diluted Shares Outstanding Adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of dilutive securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OptionsToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Options to purchase common stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OptionsToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Options To Purchase Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OptionsToPurchaseCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options to Purchase Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Lease, Description [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanFiveHundredMillionAndLessThanSevenHundredFiftyMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than five hundred million and less than seven hundred fifty million.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanFiveHundredMillionAndLessThanSevenHundredFiftyMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than Five Hundred Million And Less Than Seven Hundred Fifty Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory, Net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ShareBasedCompensationArrangementByShareBasedPaymentsAwardContractualTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Range of contractual term of option awards.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ShareBasedCompensationArrangementByShareBasedPaymentsAwardContractualTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Arrangement By Share Based Payments Award Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ShareBasedCompensationArrangementByShareBasedPaymentsAwardContractualTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock option granted, contractual term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">NET INCOME PER COMMON SHARE</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">LIABILITIES AND STOCKHOLDERS' EQUITY</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeAndOtherAccountsReceivablePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeAndOtherAccountsReceivablePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">ACCOUNTS RECEIVABLE, NET</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by (used in) operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of total purchase price was allocated to the acquired assets based on their relative fair values.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Total Purchase Price Was Allocated To The Acquired Assets Based On Their Relative Fair Values [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Total Purchase Price Was Allocated To The Acquired Assets Based On Their Relative Fair Values</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: Accumulated depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumMaturityPeriodOfCashAndCashEquivalent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maximum length of time to maturity for instruments included as cash equivalents.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumMaturityPeriodOfCashAndCashEquivalent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum Maturity Period Of Cash And Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumMaturityPeriodOfCashAndCashEquivalent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum maturity period of cash and cash equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionAccruedPreclinicalAndClinicalTrialExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition, accrued preclinical and clinical trial expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionAccruedPreclinicalAndClinicalTrialExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Accrued Preclinical And Clinical Trial Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionAccruedPreclinicalAndClinicalTrialExpenses_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accrued preclinical and clinical trial expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Arrangement, Contract to Perform for Others, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AvailableForSaleSecuritiesByAmortizedCostUnrealizedGainsOrLossesAndFairValueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities By Amortized Cost Unrealized Gains Or Losses And Fair Value [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AvailableForSaleSecuritiesByAmortizedCostUnrealizedGainsOrLossesAndFairValueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available for sale securities by amortized cost unrealized gains or losses and fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AvailableForSaleSecuritiesByAmortizedCostUnrealizedGainsOrLossesAndFairValueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Fair Values of Available for Sale Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income per share:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">INCOME TAXES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Supplemental Cash Flow Information [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental disclosures of cash flow information:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborationArrangementDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration Arrangement Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborationArrangementDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration Arrangements Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborationArrangementDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration Arrangement Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Balance Sheet Location [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease right-of-use asset, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease right-of-use assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LesseeOperatingLeaseLiabilitiesPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessee operating lease liabilities payments due after year four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LesseeOperatingLeaseLiabilitiesPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Operating Lease Liabilities Payments Due After Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LesseeOperatingLeaseLiabilitiesPaymentsDueAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Type of Arrangement and Non-arrangement Transactions [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Arrangements and Non-arrangement Transactions [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-sale [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Available-for-Sale Investments by Security type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investments, Debt and Equity Securities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments, Debt and Equity Securities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License agreement date.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Date on which strategic collaboration is entered into</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net increase (decrease) in cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Public Offering.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Public Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Potential equivalent common stock excluded</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InterimFinancialStatementTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of accounting policy for interim financial statements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InterimFinancialStatementTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interim Financial Statement [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InterimFinancialStatementTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">INTERIM FINANCIAL STATEMENTS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityInterestIssuedOrIssuableTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred, Equity Interest, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ShareRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of accounting policy for share repurchases.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ShareRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ShareRepurchases_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SHARE REPURCHASES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer A.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer A [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer A [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCompensationArrangementWithIndividualSharesAuthorizedForIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock shares available for future issuance under the Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCompensationArrangementWithIndividualSharesAuthorizedForIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Compensation Arrangement with Individual, Shares Authorized for Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Amortized Cost, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of stock options exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Exercise of stock options for common stock (shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherPrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Prepaid Expense, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherPrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToAcquireAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of total purchase price was allocated to acquire assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToAcquireAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Total Purchase Price Was Allocated To Acquire Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToAcquireAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Total Purchase Price Allocated to Acquired Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of total purchase price was allocated to the acquired assets based on their relative fair values.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of total purchase price was allocated to the acquired assets based on their relative fair values [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Current accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfRoyaltyPayableToSalesBasedMilestone_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of royalty payable to sales based milestone.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfRoyaltyPayableToSalesBasedMilestone_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Royalty Payable To Sales Based Milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfRoyaltyPayableToSalesBasedMilestone_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of royalty payable to sales based milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdvertisingCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Advertising Cost [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdvertisingCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ADVERTISING EXPENSE</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NumberOfVotesEntitlementForEachShareHeldByCommonStockHolders_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of votes entitled for each share of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NumberOfVotesEntitlementForEachShareHeldByCommonStockHolders_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of Votes Entitlement for Each Share Held by Common Stock Holders.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NumberOfVotesEntitlementForEachShareHeldByCommonStockHolders_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Votes Entitlement for Each Share Held by Common Stock Holders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ProductRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenue net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ProductRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenue Net [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ProductRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product revenue, net [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Preferred stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Comprehensive income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RESEARCH AND DEVELOPMENT</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RisksAndUncertaintiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Risks and Uncertainties [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customers.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customers [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FycompaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">FYCOMPA.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FycompaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">FYCOMPA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FycompaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FYCOMPA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sales of equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale of Equity Method Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-Based Compensation Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total purchase price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Asset Acquisition Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of stock options for common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">COMPREHENSIVE INCOME</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative and Licensing Arrangements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other comprehensive income (Note 4):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Deferred Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Deferred taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amount reclassified from accumulated other comprehensive income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt securities, available-for-sale, current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationFromSegmentTotalsToConsolidatedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reconciliation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Presentation and Significant Accounting Policies [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Presentation and Significant Accounting Policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">INTANGIBLE ASSETS, NET</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyThresholdLimitDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty threshold limit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyThresholdLimitDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Threshold Limit [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Income (Loss) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NameOfMajorCustomerDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RegistrationPaymentArrangementArrangementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Registration Payment Arrangement, Arrangement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RegistrationPaymentArrangementArrangementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Registration Payment Arrangement, Arrangement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionInvestmentSharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition investment share price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionInvestmentSharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Investment Share Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionInvestmentSharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Acquisition Investment Share Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and Cash Equivalents [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseOptionToExtend_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Option to Extend</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseOptionToExtend_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee, Operating Lease, Option to Extend</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Preferred stock, $0.001 par value, 5,000,000 shares authorized: none issued and outstanding at September 30, 2025 and December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock options to purchase shares of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling, General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling, general and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_StockholdersEquityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stockholders Equity [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_StockholdersEquityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders Equity [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_StockholdersEquityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders Equity [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AwardTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Award Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumAmortizationPeriodOfCompensationCostOnStraightLineBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maximum amount of time in which compensation cost from stock options is amortized on a straight line basis.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumAmortizationPeriodOfCompensationCostOnStraightLineBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum Amortization Period Of Compensation Cost On Straight Line Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumAmortizationPeriodOfCompensationCostOnStraightLineBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum amortization period of compensation cost on straight line basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Measurement Specific to Assets or Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfSupplementalBalanceSheetRelatedToLeaseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tabulor Disclosure of Supplemental balance Sheet Information Related To Lease.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ScheduleOfSupplementalBalanceSheetRelatedToLeaseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of Supplemental Balance Sheet related To Lease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanHundredMillionAndLessThanHundredAndTwentyFiveMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than hundred million and less than hundred and twenty five million.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanHundredMillionAndLessThanHundredAndTwentyFiveMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityInterestIssuedOrIssuableByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination, Consideration Transferred, Equity Interest, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance (shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance (shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, after Allowance for Credit Loss, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInThirdYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and asset purchase agreement payment made in third year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInThirdYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License and asset purchase agreement payment made in third year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInThirdYear_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License and asset purchase agreement payment made in third year.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidCommercialExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid commercial expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidCommercialExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Commercial Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidCommercialExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid commercialization expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (Note 12)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Leases [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeasesPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">OPERATING LEASES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidManufacturingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid manufacturing expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidManufacturingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Manufacturing Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidManufacturingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid manufacturing costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInSecondYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and asset purchase agreement payment made in second year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInSecondYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License and asset purchase agreement payment made in second year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInSecondYear_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License and asset purchase agreement payment made in second year.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWorkInProcessNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Work in Process, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWorkInProcessNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Work-in-process</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashFlowOperatingActivitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid for amounts included in the measurement of lease liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashFlowOperatingActivitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Flow, Operating Activities, Lessee [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_VamoroloneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Vamorolone member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_VamoroloneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vamorolone [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_VamoroloneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vamorolone [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer D.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer D [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer D [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Lease, Description [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TextBlockAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Text Block [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanTenMillionAndLessThanHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than ten million and less than hundred million.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanTenMillionAndLessThanHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than Ten Million And Less Than Hundred Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Equity Method Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchases of equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income Taxes, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accrued income tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreTwoHundredAndFiftyMillionAndLessThanFiveHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more two hundred and fifty million and less than five hundred million member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreTwoHundredAndFiftyMillionAndLessThanFiveHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Two Hundred And Fifty Million And Less Than Five Hundred Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SharePurchaseProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share purchase program.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SharePurchaseProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Purchase Program [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SharePurchaseProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share Purchase Program [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionConsiderationTransferredInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition consideration transferred investments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionConsiderationTransferredInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Consideration Transferred Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionConsiderationTransferredInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment in Santhera</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Basic weighted average common shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnInvestmentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Securities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnInvestmentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary Of Net Gains And Losses On Equity Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementScenarioAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Raw Materials, Net of Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Raw materials</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionConsiderationTransferredTransactionCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition, Consideration Transferred, Transaction Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionConsiderationTransferredTransactionCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionConsiderationTransferredTransactionCost_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Transaction expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfAnnualRoyaltyOnTheCompanysNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of annual royalty on the company's net sales.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfAnnualRoyaltyOnTheCompanysNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage of Annual Royalty On The Companys Net Sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfAnnualRoyaltyOnTheCompanysNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of annual royalty on the Company's net sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyLessThanHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty less than hundred million member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyLessThanHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Less Than Hundred Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyLessThanHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty Less Than Hundred Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Preferred stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_TwoThousandTwentyThreeShelfRegistrationStatementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Three Shelf Registration Statement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_TwoThousandTwentyThreeShelfRegistrationStatementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2023 Shelf Registration Statement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss) before Reclassifications, Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other comprehensive gain (loss) before reclassifications</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive gain (loss) before reclassifications</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2025 (remaining three months)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">(Increase) decrease in:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Use of Estimates, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">USE OF ESTIMATES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leasehold Improvements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leasehold improvements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Leasehold Improvements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyForSantheraSalesBasedMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty for santhera sales based milestones.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyForSantheraSalesBasedMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty For Santhera Sales Based Milestones [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plan Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_UsTreasuryBondSecuritiesCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Us Treasury Bond Securities Cash Equivalents [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_UsTreasuryBondSecuritiesCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Us Treasury Bond Securities Cash Equivalents [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_UsTreasuryBondSecuritiesCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. Treasuries&#8212;Cash equivalents [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Product and Service Sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cost of sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanThreeHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than three hundred million.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanThreeHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than Three Hundred Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanThreeHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty More Than Three Hundred Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyAgreementTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The term of the royalty payments from the first commercial sale of product under the agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyAgreementTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Agreement Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyAgreementTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty agreement period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PROPERTY AND EQUIPMENT, NET</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredResearchAndDevelopmentInventoryExpensedFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Acquired research and development inventory expensed from asset acquisition.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredResearchAndDevelopmentInventoryExpensedFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Acquired Research And Development Inventory Expensed From Asset Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredResearchAndDevelopmentInventoryExpensedFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquired research and development inventory expensed from asset acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Income [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment Income [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ExpensesIncurredInConnectionWithCollaborationAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Expenses Incurred In Connection With Collaboration Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ExpensesIncurredInConnectionWithCollaborationAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Expenses Incurred In Connection With Collaboration Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ExpensesIncurredInConnectionWithCollaborationAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expenses incurred in connection with collaboration agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasesLeaseIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Leases [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasesLeaseIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Lease Income [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased During Period, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate share repurchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares repurchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidCopayAssistanceProgram_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid copay assistance program.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidCopayAssistanceProgram_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Copay Assistance Program</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidCopayAssistanceProgram_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid co-pay assistance program</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NetSalesRoyaltyThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represents the amount used to determine the percentage of royalties for the period from the first commercial sale equal to the minimum percentage of net sales in North America for any calendar year for sales up to the amount, and maximum percentage of net sales in North America in any calendar year in excess of the amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NetSalesRoyaltyThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Sales Royalty Threshold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NetSalesRoyaltyThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net sales royalty threshold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and Acquired Intangibles, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net income before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanTwoBillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than two billion.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanTwoBillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than Two Billion [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAndLiabilitiesLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets and Liabilities, Lessee [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionCashPaidForProRatedPrepaidExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition cash paid for pro rated prepaid expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionCashPaidForProRatedPrepaidExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Cash Paid For Pro Rated Prepaid Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionCashPaidForProRatedPrepaidExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid for pro-rated prepaid expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidSubscriptionFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of asset related to consideration paid in advance for subscription fees that provides economic benefits within a future period of one year of the normal operating cycle, if longer.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidSubscriptionFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Subscription Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidSubscriptionFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid subscriptions fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfTheConsiderationPaidByAThirdPartyToAcquireThatVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of the consideration paid by a third party to acquire that voucher.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfTheConsiderationPaidByAThirdPartyToAcquireThatVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of The Consideration Paid By A Third Party To Acquire That Voucher</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfTheConsiderationPaidByAThirdPartyToAcquireThatVoucher_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of the consideration paid by a third party to acquire that voucher</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total inventory, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and cash equivalents &#8211; end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and cash equivalents &#8211; beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Paid, Excluding Capitalized Interest, Operating Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid for interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Range [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_UpFrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Up-front&#160;payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_UpFrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Up Front Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_UpFrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Up front payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RevenueMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RevenueMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue milestones.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RevenueMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement, Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-cash stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of Individual [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Title of Individual [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of accounting policy for prepaid expenses and other current assets. This disclosure may include the types of prepaid expenses and other current assets and how these are recognize in expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expenses And Other Current Assets [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PREPAID EXPENSES AND OTHER CURRENT ASSETS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PaymentOnMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment on milestone payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PaymentOnMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment On Milestone Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PaymentOnMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment on milestone payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionInventoryCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition, inventory current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionInventoryCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Inventory Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionInventoryCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">REVENUE RECOGNITION</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementClassOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalizedContractCostAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capitalized Contract Cost, Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalizedContractCostAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capitalized amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary Of Basis Of Presentation And Significant Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Basis Of Presentation And Significant Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary Of Basis Of Presentation And Significant Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-sale, Realized Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Realized gains losses from available for sale securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingCostsAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Costs and Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingCostsAndExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating costs and expenses:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Instruments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial Instruments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Payments, Due Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdvertisingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Advertising Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted weighted average common shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Diluted weighted average common shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net current period other comprehensive gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized gain (loss) on available-for-sale securities, net of tax of $9, $0, $19 and $4, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAcquiredIntangiblesForRUZURGIMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License and acquired intangibles for RUZURGI.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAcquiredIntangiblesForRUZURGIMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License And Acquired Intangibles For RUZURGI [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAcquiredIntangiblesForRUZURGIMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and Acquired Intangibles for RUZURGI [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SalesRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Benchmark [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SalesRevenueNetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue Benchmark [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioUnspecifiedDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasurySecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US Treasury Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasurySecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S. Treasuries [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Operating Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of operating segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_BeforeAgreementOfCompanyLeasedSpaces_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Before agreement of company leased spaces.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_BeforeAgreementOfCompanyLeasedSpaces_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Before Agreement Of Company Leased Spaces</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_BeforeAgreementOfCompanyLeasedSpaces_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Before agreement of company leased spaces</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">General and Administrative Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StockRepurchaseProgramExpirationDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Repurchase Program, Expiration Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StockRepurchaseProgramExpirationDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share repurchase program, expiration date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Net Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and acquired intangibles, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanHundredAndTwentyFiveMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than hundred and twenty five million.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanHundredAndTwentyFiveMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than Hundred And Twenty Five Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PaymentOfLiabilitiesArisingFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of liabilities arising from asset acquisition.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PaymentOfLiabilitiesArisingFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of Liabilities Arising From Asset Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PaymentOfLiabilitiesArisingFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment of liabilities arising from asset acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Useful life of assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RECENTLY ISSUED ACCOUNTING STANDARDS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee, Operating Lease, Liability, Maturity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquistionPrepaidCommercializationFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquistion, prepaid commercialization fees.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquistionPrepaidCommercializationFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquistion, Prepaid Commercialization Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquistionPrepaidCommercializationFees_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid commercialization expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNoteTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss) Note [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNoteTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer C.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer C [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer C [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAcquiredIntangiblesForFycompaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License And Acquired Intangibles For FYCOMPA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAcquiredIntangiblesForFycompaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and Acquired Intangibles for FYCOMPA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionLicenseAndAcquiredIntangiblesForFycompa_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition, license and acquired intangibles for FYCOMPA&#174;.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionLicenseAndAcquiredIntangiblesForFycompa_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition License And Acquired Intangibles For Fycompa</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionLicenseAndAcquiredIntangiblesForFycompa_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">License and acquired intangibles for FYCOMPA&#174;</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltiesExpensePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalties Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltiesExpensePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalties Expense [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltiesExpensePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">ROYALTIES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ThresholdNetSalesPercentageDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Threshold net sales percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ThresholdNetSalesPercentageDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Threshold Net Sales Percentage [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Collaborative Arrangements [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanHundredMillionAndLessThanTwoHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than hundred million and less than two hundred million.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanHundredMillionAndLessThanTwoHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than Hundred Million And Less Than Two Hundred Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfRoyaltyPayableToNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represents the percentage applied to net sales to determine the amount payable as part of the agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfRoyaltyPayableToNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Royalty Payable To Net Sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfRoyaltyPayableToNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of royalty on net sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Research and Development Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Leases [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate purchase price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Repurchase of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_TwoThousandEighteenStockIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two Thousand Eighteen Stock Incentive Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_TwoThousandEighteenStockIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Eighteen Stock Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_TwoThousandEighteenStockIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Two Thousand Eighteen Stock Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerEMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer E [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerEMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer E [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerEMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer E.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AmortizationExpensesOfIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AmortizationExpensesOfIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization Expenses of Intangible Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AmortizationExpensesOfIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits that Would Impact Effective Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized Tax Benefits that Would Impact Effective Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComputerEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Computer Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComputerEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Computer Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedPurchasesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued purchases current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedPurchasesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Purchases Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedPurchasesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued purchases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWriteDown_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory write-offs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryWriteDown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Write-down</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Inventory, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CalendarYear2026Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Calendar Year 2026 Member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CalendarYear2026Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Calendar Year 2026 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Rent expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ComponentsOfRevenueRecognizedAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Components Of revenue recognized.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ComponentsOfRevenueRecognizedAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Components Of Revenue Recognized [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyThresholdLimitAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty threshold limit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyThresholdLimitAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Threshold Limit [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Securities, FV-NI, Unrealized Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized net gains (losses) recognized during the period on equity securities still held at the reporting date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Purchase Obligation, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase commitment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasePayments_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating cash flows</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASSETS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CalendarYears2022Through2025Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Calendar Years 2022 Through 2025 Member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CalendarYears2022Through2025Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Calendar Years 2022 Through 2025 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Reclassifications out of Accumulated Other Comprehensive Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskBenchmarkDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investing Activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock option exercise price range, Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgreementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgreementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Agreement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and Development [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFvNiGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Securities, FV-NI, Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFvNiGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net gains (losses) recognized during the period on equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquitySecuritiesFvNiGainLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Change in fair value of equity securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanTwoHundredMillionAndLessThanThreeHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than two hundred million and less than three hundred million.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanTwoHundredMillionAndLessThanThreeHundredMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than Two Hundred Million And Less Than Three Hundred Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tabular disclosure of prepaid expenses and other current assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid expenses and other current assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidExpensesAndOtherCurrentAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FAIR VALUE MEASUREMENTS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_EquityCompensationPlanSharesAuthorizedForIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock shares available for future issuance under the Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_EquityCompensationPlanSharesAuthorizedForIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Compensation Plan Shares Authorized For Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_EquityCompensationPlanSharesAuthorizedForIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Equity compensation plan shares authorized for issuance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseObligationDueInNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase Obligation, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseObligationDueInNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase commitment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from exercise of stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborationAgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborationAgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration Agreement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Finite lived intangible assets amortization expense after year four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite Lived Intangible Assets Amortization Expense After Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure of Compensation Related Costs, Share-based Payments [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Disclosure of Compensation Related Costs, Share-based Payments [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized compensation expense related to non-vested stock compensation awards granted under the Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Liabilities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase (decrease) in:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration risk, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by (used in) investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfMinimumRoyaltyPayableToNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of minimum royalty payable to net sales.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfMinimumRoyaltyPayableToNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Minimum Royalty Payable To Net Sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PercentageOfMinimumRoyaltyPayableToNetSales_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of minimum royalty payable to net sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementForRuzurgiMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License agreement for ruzurgi.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAgreementForRuzurgiMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License Agreement For RUZURGI [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money market funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Collaborative Arrangement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanOneBillionAndLessThanTwoBillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty more than one billion and less than two billion.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyMoreThanOneBillionAndLessThanTwoBillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty More Than One Billion And Less Than Two Billion [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyForAdditionalIndicationsAndMilestonesOfUpToFiftyMillionMoreMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty for additional indications and milestones of up to fifty million more.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyForAdditionalIndicationsAndMilestonesOfUpToFiftyMillionMoreMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty For Additional Indications And Milestones Of Up To Fifty Million More [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">2025 (remaining three months)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other non-current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredInventorySamplesExpensedFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Acquired inventory samples expensed from asset acquisition.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredInventorySamplesExpensedFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Acquired Inventory Samples Expensed From Asset Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AcquiredInventorySamplesExpensedFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquired inventory samples expensed from asset acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring and Nonrecurring [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Measurements, Recurring and Nonrecurring [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndOtherRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License and other revenue.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndOtherRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License And Other Revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndOtherRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and other revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StockRepurchaseProgramAuthorizedAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchase Program, Authorized Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StockRepurchaseProgramAuthorizedAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share repurchase program, authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement Location [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyExchangeRateTranslation1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Currency Exchange Rate, Translation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ForeignCurrencyExchangeRateTranslation1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign Currency Exchange Rate, Translation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Finite-Lived Intangible Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Finite-Lived Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee-related Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued compensation and benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financing Activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable and Accrued Liabilities Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Expenses and Other Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseCurrentAndFiveSucceedingFiscalYearsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Payments, Due</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyLessThanTwoHundredFiftyMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty less than two hundred fifty million.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyLessThanTwoHundredFiftyMillionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Less Than Two Hundred Fifty Million [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumAmountOfCommonStockThatCanBeIssuedUnderShelfRegistrationStatement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maximum dollar amount of common stock to be issued under shelf registration statement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumAmountOfCommonStockThatCanBeIssuedUnderShelfRegistrationStatement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum Amount Of Common Stock That Can Be Issued Under Shelf Registration Statement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MaximumAmountOfCommonStockThatCanBeIssuedUnderShelfRegistrationStatement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum dollar amount of common stock to be issued under shelf registration statement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborativeArrangementMilestonePaymentObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement milestone payment obligation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborativeArrangementMilestonePaymentObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Milestone Payment Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CollaborativeArrangementMilestonePaymentObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative arrangement, milestone payment obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ComponentsOfRevenueRecognizedDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Components Of revenue recognized.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ComponentsOfRevenueRecognizedDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Components Of Revenue Recognized [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidInsurance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid insurance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock upon vesting of restricted stock units, net (Share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MajorCustomersAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Investment Income [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Investment Income [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Comprehensive Income [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Range [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of basis of presentation and significant accounting policies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, $0.001 par value, 200,000,000 shares authorized; 123,264,583 shares and 120,879,099 shares issued and outstanding at September 30, 2025 and December 31, 2024, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConsolidationPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Consolidation, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConsolidationPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PRINCIPLES OF CONSOLIDATION</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfWeightedAverageNumberOfSharesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Weighted Average Number of Shares [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfWeightedAverageNumberOfSharesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic and Dilutive Weighted Average Common Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedNonClinicalAndClinicalTrialExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Carrying value as of the balance sheet date of obligations incurred through that date and payable pertaining to non clinical and clinical trial expenses. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedNonClinicalAndClinicalTrialExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Non Clinical And Clinical Trial Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedNonClinicalAndClinicalTrialExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued preclinical and clinical trial expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition equity interests issued or issuable number of shares issued.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Equity Interests Issued Or Issuable Number Of Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset acquisition equity interests issued or issuable number of shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Finite-Lived, Future Amortization Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_KyePharmaceuticalsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">KYE Pharmaceuticals.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_KyePharmaceuticalsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">KYE Pharmaceuticals [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Preferred stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued interest payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment, Tax Withholding, Share-based Payment Arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment of employee withholding tax related to stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AmountOfMinimumRoyaltyPayableMaturityTermsNotMet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount of minimum royalty payable maturity terms not met</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AmountOfMinimumRoyaltyPayableMaturityTermsNotMet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amount Of Minimum Royalty Payable Maturity Terms Not Met</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AmountOfMinimumRoyaltyPayableMaturityTermsNotMet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of minimum royalty payable maturity terms not met.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock option exercise price range, Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RepurchaseOfCommonStockAveragePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Average price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RepurchaseOfCommonStockAveragePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Repurchase Of Common Stock Average Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RepurchaseOfCommonStockAveragePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Repurchase of common stock average price per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireInProcessResearchAndDevelopment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Acquisition of in-process research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireInProcessResearchAndDevelopment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire in Process Research and Development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PurchasePriceOfAnAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Up front payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PurchasePriceOfAnAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Purchase price of an asset acquisition.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PurchasePriceOfAnAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase price of an asset acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NonCashChangeInRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of cash change in right of use asset.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NonCashChangeInRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non cash change in right of use asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NonCashChangeInRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reduction in the carrying amount of right-of-use asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Expected Amortization, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax provision</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-sale, Unrealized Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gross Unrealized Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Unrealized Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Initial cash payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Productive Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireProductiveAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments to acquire productive assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross proceeds from issuance of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from issuance of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicensedAndAcquiredIntangiblesForAgamreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Licensed and acquired intangibles for AGAMREE.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicensedAndAcquiredIntangiblesForAgamreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Licensed And Acquired Intangibles For AGAMREE [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">CONCENTRATION OF RISK</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyForAdditionalIndicationsAndMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty for additional indications and milestones.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RoyaltyForAdditionalIndicationsAndMilestonesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty For Additional Indications And Milestones [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Inventory reserve.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory reserve</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryReserve_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Reserve</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accumulated other comprehensive income (loss) (Note 4)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RegistrationPaymentArrangementByArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Registration Payment Arrangement by Arrangement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RegistrationPaymentArrangementByArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Registration Payment Arrangement by Arrangement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Allowance for expected credit losses, written off</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss, Writeoff</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Period Axis.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Period [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Net [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">INVENTORY</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, Plant and Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_U.s.RightsForFycompaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">U.S. Rights for FYCOMPA.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_U.s.RightsForFycompaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">U.S. Rights for FYCOMPA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInFirstYear_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License and asset purchase agreement payment made in first year.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInFirstYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">License And Asset Purchase Agreement Payment Made in First Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInFirstYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License and asset purchase agreement payment made in first year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PeriodDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Period Domain.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PeriodDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Period [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value of Financial Instruments, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FAIR VALUE OF FINANCIAL INSTRUMENTS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">STOCK-BASED COMPENSATION</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CommitmentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CommitmentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CommitmentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling, General and Administrative Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Selling, General and Administrative [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MinimumRoyaltyAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Royalty Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MinimumRoyaltyAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum royalty amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_MinimumRoyaltyAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum royalty amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock, net (shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock issued during the period shares new issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Significant Segment Expenses of Stock-based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgreementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Agreement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of Individual [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Relationship to Entity [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_DydoPharmaIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dydo pharma inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_DydoPharmaIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dydo Pharma Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RightOfUseAssetsObtainedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use assets obtained in exchange for lease obligations:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RightOfUseAssetsObtainedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Right of Use Assets Obtained</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_RightOfUseAssetsObtainedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right of Use Assets Obtained [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LiabilitiesArisingFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Liabilities arising from asset acquisition.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LiabilitiesArisingFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities Arising From Asset Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_LiabilitiesArisingFromAssetAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities arising from asset acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionBaseCashPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition base cash payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionBaseCashPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Base Cash Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionBaseCashPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Base cash payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgamreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AGAMREE [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgamreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">AGAMREE [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgamreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">AGAMREE.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Remaining Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average remaining lease term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgreementsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Agreements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgreementsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Agreements Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AgreementsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">CASH AND CASH EQUIVALENTS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property, Plant and Equipment, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock upon vesting of restricted stock units, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfIntangibleAssetsFinitelived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment of Intangible Assets, Finite-Lived</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOfIntangibleAssetsFinitelived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment charges recognized on definite-lived intangibles</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Operating income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-based Payment Arrangement, Noncash Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionConsiderationTransferred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition, Consideration Transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionConsiderationTransferred_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total purchase consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NetSalesBasedMilestoneToRoyaltyThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net sales based milestone to royalty threshold.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NetSalesBasedMilestoneToRoyaltyThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Sales Based Milestone To Royalty Threshold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_NetSalesBasedMilestoneToRoyaltyThreshold_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net sales based milestone to royalty threshold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OperatingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OperatingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OperatingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating costs and expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments of Stock Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment of fees in connection with issuance of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ThresholdNetSalesPercentageAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Threshold net sales percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ThresholdNetSalesPercentageAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Threshold Net Sales Percentage [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Discount Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating lease liabilities, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease liability &#8211; non-current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating lease liability, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by (used in) financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Aggregate Amount Paid for the Assets Acquired</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPropertyAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset acquisition, property and equipment, net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPropertyAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition Property And Equipment Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AssetAcquisitionPropertyAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Authority [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Tax Authority [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer B.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer B [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CustomerBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer B [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement Location [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Statement Location [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ReimbursementOnBasePurchasePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reimbursement on base purchase price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ReimbursementOnBasePurchasePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reimbursement On Base Purchase Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ReimbursementOnBasePurchasePrice_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Reimbursement on base purchase price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Furniture and Fixtures [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Furniture and equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Furniture and Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedLicenseFeesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Carrying value as of the balance sheet date of obligations incurred through that date and payable for license fees. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedLicenseFeesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued License Fees Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_AccruedLicenseFeesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued license fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FirdapseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">FIRDAPSE.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FirdapseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">FIRDAPSE [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_FirdapseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FIRDAPSE [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryReserveAndWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventory reserve and write-offs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryReserveAndWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Reserve And Write Offs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_InventoryReserveAndWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Inventory Reserve And Write Offs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OtherNoncurrentAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other noncurrent accrued expenses and other liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OtherNoncurrentAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Noncurrent Accrued Expenses And Other Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_OtherNoncurrentAccruedExpensesAndOtherLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Non-current accrued expenses and other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SchedulesOfConcentrationOfRiskByRiskFactorTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedules of Concentration of Risk, by Risk Factor [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SchedulesOfConcentrationOfRiskByRiskFactorTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Percentage of the Company's Total Net Product Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenuesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenues [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenuesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenues:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidResearchFee_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of asset related to consideration paid in advance for research and product development activities that provide economic benefits within a future period of one year or the normal operating cycle, if longer.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidResearchFee_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Research Fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidResearchFee_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid research fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidConferenceAndTravelExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid conference and travel expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidConferenceAndTravelExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Conference And Travel Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_PrepaidConferenceAndTravelExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid conference and travel expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Local Phone Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedGain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-sale, Unrealized Gain</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesGrossUnrealizedGain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Unrealized Gains</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average shares outstanding:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyAgreementTermsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Agreement Terms [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Policies [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ClosingMarketPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Closing market price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ClosingMarketPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Closing Market Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ClosingMarketPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Closing Market Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer, Excluding Assessed Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ContingentConsiderationArrangementsContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contingent Consideration Arrangements Contingent Consideration Liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ContingentConsiderationArrangementsContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contingent Consideration Arrangements Contingent Consideration Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_ContingentConsiderationArrangementsContingentConsiderationLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingent consideration liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CommitmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CommitmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_CommitmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_TwoThousandTwentyShelfRegistrationStatementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand twenty shelf registration statement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cprx_TwoThousandTwentyShelfRegistrationStatementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Shelf Registration Statement [Member]</link:label>
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  <xsd:element id="cprx_PercentageOfTheConsiderationPaidByAThirdPartyToAcquireThatVoucher" name="PercentageOfTheConsiderationPaidByAThirdPartyToAcquireThatVoucher" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_AmountOfMinimumRoyaltyPayableMaturityTermsNotMet" name="AmountOfMinimumRoyaltyPayableMaturityTermsNotMet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="cprx_CustomerEMember" name="CustomerEMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="cprx_AssetAcquisitionPropertyAndEquipmentNet" name="AssetAcquisitionPropertyAndEquipmentNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInThirdYear" name="LicenseAndAssetPurchaseAgreementPaymentMadeInThirdYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_VamoroloneMember" name="VamoroloneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PurchasePriceConsiderationForIntangibleAssetsAcquired" name="PurchasePriceConsiderationForIntangibleAssetsAcquired" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_AssetAcquisitionBaseCashPayment" name="AssetAcquisitionBaseCashPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_InventoryWriteDownExpectedToBeReimbursed" name="InventoryWriteDownExpectedToBeReimbursed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_ThresholdNetSalesPercentageDomain" name="ThresholdNetSalesPercentageDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyForAdditionalIndicationsAndMilestonesMember" name="RoyaltyForAdditionalIndicationsAndMilestonesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesLineItems" name="SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_ProductRevenueNetMember" name="ProductRevenueNetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_SharePurchaseProgramMember" name="SharePurchaseProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AssetAcquistionPrepaidCommercializationFees" name="AssetAcquistionPrepaidCommercializationFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_RoyaltyMoreThanHundredMillionAndLessThanHundredAndTwentyFiveMillionMember" name="RoyaltyMoreThanHundredMillionAndLessThanHundredAndTwentyFiveMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_NonCashChangeInRightOfUseAsset" name="NonCashChangeInRightOfUseAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_CustomerBMember" name="CustomerBMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock" name="PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_TwoThousandTwentyShelfRegistrationStatementMember" name="TwoThousandTwentyShelfRegistrationStatementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PrepaidCopayAssistanceProgram" name="PrepaidCopayAssistanceProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_UpFrontPayment" name="UpFrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_ContingentConsiderationArrangementsContingentConsiderationLiability" name="ContingentConsiderationArrangementsContingentConsiderationLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_RepurchaseOfCommonStockAveragePricePerShare" name="RepurchaseOfCommonStockAveragePricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_MaximumMaturityPeriodOfCashAndCashEquivalent" name="MaximumMaturityPeriodOfCashAndCashEquivalent" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_PublicOfferingMember" name="PublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_LicenseAgreementWithBioMarinMember" name="LicenseAgreementWithBioMarinMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyMoreThanHundredMillionAndLessThanTwoHundredMillionMember" name="RoyaltyMoreThanHundredMillionAndLessThanTwoHundredMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PrepaidExpensesAndOtherCurrentAssetsTableTextBlock" name="PrepaidExpensesAndOtherCurrentAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_AgreementDomain" name="AgreementDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PrepaidExpensesAndOtherCurrentAssetsTextBlock" name="PrepaidExpensesAndOtherCurrentAssetsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_CollaborativeArrangementMilestonePaymentObligation" name="CollaborativeArrangementMilestonePaymentObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_RoyaltyThresholdLimitDomain" name="RoyaltyThresholdLimitDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AssetAcquisitionLicenseAndAcquiredIntangiblesForFycompa" name="AssetAcquisitionLicenseAndAcquiredIntangiblesForFycompa" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_CustomerCMember" name="CustomerCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInFirstYear" name="LicenseAndAssetPurchaseAgreementPaymentMadeInFirstYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_AfterAgreementOfCompanyLeasedSpaces" name="AfterAgreementOfCompanyLeasedSpaces" type="dtr-types:areaItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesTable" name="SummaryOfBasisOfPresentationAndSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTableTextBlock" name="ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_CollaborationArrangementDisclosureAbstract" name="CollaborationArrangementDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PercentageOfRoyaltyPayableToSalesBasedMilestone" name="PercentageOfRoyaltyPayableToSalesBasedMilestone" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_PaymentOfLiabilitiesArisingFromAssetAcquisition" name="PaymentOfLiabilitiesArisingFromAssetAcquisition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_RoyaltyForAdditionalIndicationsAndMilestonesOfUpToFiftyMillionMoreMember" name="RoyaltyForAdditionalIndicationsAndMilestonesOfUpToFiftyMillionMoreMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AmortizationExpensesOfIntangibleAsset" name="AmortizationExpensesOfIntangibleAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_PaymentOnMilestonePayment" name="PaymentOnMilestonePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_CustomerAMember" name="CustomerAMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_NetSalesBasedMilestoneToRoyaltyThreshold" name="NetSalesBasedMilestoneToRoyaltyThreshold" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_NumberOfTradingDaysFromReceiptOfTheNoticeLetter" name="NumberOfTradingDaysFromReceiptOfTheNoticeLetter" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_ClosingMarketPrice" name="ClosingMarketPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_MaximumAmortizationPeriodOfCompensationCostOnStraightLineBasis" name="MaximumAmortizationPeriodOfCompensationCostOnStraightLineBasis" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_CollaborationAgreementDomain" name="CollaborationAgreementDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_CommitmentsTable" name="CommitmentsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToAcquireAssetsTableTextBlock" name="ScheduleOfTotalPurchasePriceWasAllocatedToAcquireAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_LicenseAndOtherRevenueMember" name="LicenseAndOtherRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AcquiredInProcessResearchAndDevelopment" name="AcquiredInProcessResearchAndDevelopment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_AssetAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" name="AssetAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_StockholdersEquityLineItems" name="StockholdersEquityLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_LicenseAgreementDate" name="LicenseAgreementDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_PrepaidConferenceAndTravelExpenses" name="PrepaidConferenceAndTravelExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_TwoThousandEighteenStockIncentivePlanMember" name="TwoThousandEighteenStockIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_OtherNoncurrentAccruedExpensesAndOtherLiabilities" name="OtherNoncurrentAccruedExpensesAndOtherLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_PrepaidCommercialExpenses" name="PrepaidCommercialExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_ReimbursementOnBasePurchasePrice" name="ReimbursementOnBasePurchasePrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_AssetAcquisationDueToLicensorCurrent" name="AssetAcquisationDueToLicensorCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_OptionsToPurchaseCommonStockMember" name="OptionsToPurchaseCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AgreementAxis" name="AgreementAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_NetSalesBasedMilestoneUponAchievementOfRevenues" name="NetSalesBasedMilestoneUponAchievementOfRevenues" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_ProductRevenueAcquisitionDate" name="ProductRevenueAcquisitionDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_PurchasePriceOfAnAssetAcquisition" name="PurchasePriceOfAnAssetAcquisition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_RoyaltyMoreThanThreeHundredMillionMember" name="RoyaltyMoreThanThreeHundredMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_CollaborationAgreementAxis" name="CollaborationAgreementAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_DydoPharmaIncMember" name="DydoPharmaIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyMoreThanFiveHundredMillionAndLessThanSevenHundredFiftyMillionMember" name="RoyaltyMoreThanFiveHundredMillionAndLessThanSevenHundredFiftyMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyMoreThanTenMillionAndLessThanHundredMillionMember" name="RoyaltyMoreThanTenMillionAndLessThanHundredMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_LiabilitiesArisingFromAssetAcquisition" name="LiabilitiesArisingFromAssetAcquisition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_LesseeOperatingLeaseLiabilitiesPaymentsDueAfterYearFour" name="LesseeOperatingLeaseLiabilitiesPaymentsDueAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_LicenseAgreementForRuzurgiMember" name="LicenseAgreementForRuzurgiMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_LicenseAgreementTable" name="LicenseAgreementTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyLessThanHundredMillionMember" name="RoyaltyLessThanHundredMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyMoreThanTwoHundredMillionAndLessThanThreeHundredMillionMember" name="RoyaltyMoreThanTwoHundredMillionAndLessThanThreeHundredMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AssetAcquisitionPurchasePriceConsideration" name="AssetAcquisitionPurchasePriceConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" name="FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_CustomerDMember" name="CustomerDMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_FirdapseMember" name="FirdapseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AgamreeMember" name="AgamreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PresidentAndChiefExecutiveOfficerMember" name="PresidentAndChiefExecutiveOfficerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyMoreThanTwoBillionMember" name="RoyaltyMoreThanTwoBillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyMoreThanHundredAndTwentyFiveMillionMember" name="RoyaltyMoreThanHundredAndTwentyFiveMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AssetAcquisitionInvestmentSharePrice" name="AssetAcquisitionInvestmentSharePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_OperatingExpense" name="OperatingExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_InventoryReserve" name="InventoryReserve" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_RoyaltyMoreSevenHundredAndFiftyMillionAndLessThanOneBillionMember" name="RoyaltyMoreSevenHundredAndFiftyMillionAndLessThanOneBillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_TwoThousandTwentyThreeShelfRegistrationStatementMember" name="TwoThousandTwentyThreeShelfRegistrationStatementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_ScheduleOfSupplementalBalanceSheetRelatedToLeaseTableTextBlock" name="ScheduleOfSupplementalBalanceSheetRelatedToLeaseTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_CalendarYears2022Through2025Member" name="CalendarYears2022Through2025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_LicenseAndAcquiredIntangiblesForFycompaMember" name="LicenseAndAcquiredIntangiblesForFycompaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RightOfUseAssetsObtainedAbstract" name="RightOfUseAssetsObtainedAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_U.s.RightsForFycompaMember" name="U.s.RightsForFycompaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PercentageOfMinimumRoyaltyPayableToNetSales" name="PercentageOfMinimumRoyaltyPayableToNetSales" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_AssetAcquisitionInventoryCurrent" name="AssetAcquisitionInventoryCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_AcquiredInventorySamplesExpensedFromAssetAcquisition" name="AcquiredInventorySamplesExpensedFromAssetAcquisition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_PrepaidManufacturingExpense" name="PrepaidManufacturingExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_DateOfCommercialLaunch" name="DateOfCommercialLaunch" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_AccruedLicenseFeesCurrent" name="AccruedLicenseFeesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_PercentageOfRoyaltyPayableToNetSales" name="PercentageOfRoyaltyPayableToNetSales" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_CalendarYear2026Member" name="CalendarYear2026Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AssetAcquisitionPrepaidExpensesAndOtherCurrentAssets" name="AssetAcquisitionPrepaidExpensesAndOtherCurrentAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_LicensedAndAcquiredIntangiblesForAgamreeMember" name="LicensedAndAcquiredIntangiblesForAgamreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyMoreTwoHundredAndFiftyMillionAndLessThanFiveHundredMillionMember" name="RoyaltyMoreTwoHundredAndFiftyMillionAndLessThanFiveHundredMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AccruedPurchasesCurrent" name="AccruedPurchasesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesLineItems" name="ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PrepaidSubscriptionFees" name="PrepaidSubscriptionFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_MinimumRoyaltyAmount" name="MinimumRoyaltyAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_FycompaMember" name="FycompaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AssetAcquisitionValue" name="AssetAcquisitionValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_AccruedGrossToNetRevenueLiabilities" name="AccruedGrossToNetRevenueLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_InventoryReserveAndWriteOffs" name="InventoryReserveAndWriteOffs" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_ThresholdNetSalesPercentageAxis" name="ThresholdNetSalesPercentageAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AccruedNonClinicalAndClinicalTrialExpenses" name="AccruedNonClinicalAndClinicalTrialExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_ComponentsOfRevenueRecognizedDomain" name="ComponentsOfRevenueRecognizedDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PeriodDomain" name="PeriodDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyLessThanTwoHundredFiftyMillionMember" name="RoyaltyLessThanTwoHundredFiftyMillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AvailableForSaleSecuritiesByAmortizedCostUnrealizedGainsOrLossesAndFairValueTableTextBlock" name="AvailableForSaleSecuritiesByAmortizedCostUnrealizedGainsOrLossesAndFairValueTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_AssetAcquisitionCashPaidForProRatedPrepaidExpenses" name="AssetAcquisitionCashPaidForProRatedPrepaidExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_ShareRepurchases" name="ShareRepurchases" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_InterimFinancialStatementTextBlock" name="InterimFinancialStatementTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_BeforeAgreementOfCompanyLeasedSpaces" name="BeforeAgreementOfCompanyLeasedSpaces" type="dtr-types:areaItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_LicenseAndAssetPurchaseAgreementPaymentMadeInSecondYear" name="LicenseAndAssetPurchaseAgreementPaymentMadeInSecondYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_PeriodAxis" name="PeriodAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_DueFromCollaborativeAndLicencingArrangements" name="DueFromCollaborativeAndLicencingArrangements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_ExpensesIncurredInConnectionWithCollaborationAgreement" name="ExpensesIncurredInConnectionWithCollaborationAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_MinimumRoyalty" name="MinimumRoyalty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_CommitmentsLineItems" name="CommitmentsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_CustomersMember" name="CustomersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_KyePharmaceuticalsMember" name="KyePharmaceuticalsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyMoreThanOneBillionAndLessThanTwoBillionMember" name="RoyaltyMoreThanOneBillionAndLessThanTwoBillionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_MaximumAmountOfCommonStockThatCanBeIssuedUnderShelfRegistrationStatement" name="MaximumAmountOfCommonStockThatCanBeIssuedUnderShelfRegistrationStatement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_NumberOfVotesEntitlementForEachShareHeldByCommonStockHolders" name="NumberOfVotesEntitlementForEachShareHeldByCommonStockHolders" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cprx_ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTable" name="ScheduleOfTotalPurchasePriceWasAllocatedToTheAcquiredAssetsBasedOnTheirRelativeFairValuesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyAgreementTerm" name="RoyaltyAgreementTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_LicenseAndAssetPurchaseAgreementMember" name="LicenseAndAssetPurchaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyThresholdLimitAxis" name="RoyaltyThresholdLimitAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_AcquiredResearchAndDevelopmentInventoryExpensedFromAssetAcquisition" name="AcquiredResearchAndDevelopmentInventoryExpensedFromAssetAcquisition" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_AccretionOfDiscount" name="AccretionOfDiscount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_EquityCompensationPlanSharesAuthorizedForIssuance" name="EquityCompensationPlanSharesAuthorizedForIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cprx_AssetAcquisitionConsiderationTransferredInvestments" name="AssetAcquisitionConsiderationTransferredInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cprx_PrepaidResearchFee" name="PrepaidResearchFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_RoyaltiesExpensePolicyTextBlock" name="RoyaltiesExpensePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_AssetAcquisitionAccruedPreclinicalAndClinicalTrialExpenses" name="AssetAcquisitionAccruedPreclinicalAndClinicalTrialExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_LicenseAgreementLineItems" name="LicenseAgreementLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_RoyaltyForSantheraSalesBasedMilestonesMember" name="RoyaltyForSantheraSalesBasedMilestonesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_ShareBasedCompensationArrangementByShareBasedPaymentsAwardContractualTerm" name="ShareBasedCompensationArrangementByShareBasedPaymentsAwardContractualTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_RevenueMilestones" name="RevenueMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cprx_AssetAcquisitionPercentageOfOutstandingOrdinaryShares" name="AssetAcquisitionPercentageOfOutstandingOrdinaryShares" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_LicenseAndAcquiredIntangiblesForRUZURGIMember" name="LicenseAndAcquiredIntangiblesForRUZURGIMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_ComponentsOfRevenueRecognizedAxis" name="ComponentsOfRevenueRecognizedAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_PercentageOfAnnualRoyaltyOnTheCompanysNetSales" name="PercentageOfAnnualRoyaltyOnTheCompanysNetSales" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cprx_UsTreasuryBondSecuritiesCashEquivalentsMember" name="UsTreasuryBondSecuritiesCashEquivalentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cprx_StockholdersEquityTable" name="StockholdersEquityTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
</xsd:schema>
