Document And Entity Information
Expected dividend yield
Derivative Instrument Related to 2024 SSCP Notes [Member]
Represents the derivative instrument related to the 2024 SSCP Notes.
Note To Financial Statement Details Textual
Derivative Instrument Related to 2024 SSCP Notes Immediately Preceding 2024 SSCPN Amendment [Member]
Represents the derivative instrument related to the 2024 SSCP Notes immediately preceding the 2024 SSCPN Amendment.
Significant Accounting Policies
Note 3 - Cash and Cash Equivalents
Note 4 - Prepaid Expenses and Other Current Assets
Risk-free interest rate
Note 5 - Property and Equipment, Net
Note 6 - Accrued Liabilities
Derivative Instrument Related to 2024 SSCP Notes Immediately Following 2024 SSCPN Amendment and 2025 SSCP Notes at Issuance [Member]
Represents the derivative instrument related to 2024 SSCP Notes immediately following 2024 SSCPN Amendment and 2025 SSCP Notes at issuance.
Note 7 - Leases
Note 8 - Notes Payable and Convertible Notes Payable
Note 10 - Income Taxes
Category of Item Purchased [Axis]
Note 11 - Benefit Plans
Long-Term Purchase Commitment, Category of Item Purchased [Domain]
Note 12 - Fair Value
Note 13 - Capital Stock
Unrealized loss on available-for-sale securities
Note 14 - Net Loss Per Share
Note 15 - Related Party Transactions
Expected stock price volatility
Note 16 - Geographic and Segment Information
us-gaap_LiabilitiesCurrent
Total current liabilities
Note 3 - Cash and Cash Equivalents - Available-for-sale Securities (Details)
Note 4 - Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Details)
Note 5 - Property and Equipment, Net - Schedule of Property and Equipment, Net (Details)
Expected term of options (in years) (Year)
Note 5 - Property and Equipment, Net - Schedule of Depreciation Expense (Details)
Note 6 - Accrued Liabilities - Schedule of Accrued Liabilities (Details)
Note 7 - Leases - Maturity Analysis of Leases (Details)
Note 7 - Leases - Components of Lease Cost (Details)
Note 7 - Leases - Supplemental Cash Flow Information (Details)
Note 8 - Notes Payable and Convertible Notes Payable - Long-term Debt (Details)
Note 8 - Notes Payable and Convertible Notes Payable - Interest Expense (Details)
Note 8 - Notes Payable and Convertible Notes Payable - Schedule of Future Payments (Details)
Note 10 - Income Taxes - Components of Income (Loss) Before Income Taxes (Details)
Note 10 - Income Taxes - Reconciliation of Income Tax (Details)
Note 10 - Income Taxes - Significant Components of Deferred Tax Assets (Liabilities) (Details)
Note 11 - Benefit Plans - Stock-based Compensation Expense (Details)
Note 11 - Benefit Plans - Activity Related to Outstanding Stock Options (Details)
Note 11 - Benefit Plans - Assumptions of Stock Options (Details)
Note 11 - Benefit Plans - Activity Related to Restricted Stock Awards (Details)
Forfeited, weighted average grant date fair value (in dollars per share)
Note 12 - Fair Value - Assets and Liabilities Measured on a Recurring Basis (Details)
The 2022 MD Loan [Member]
Represents the 2022 MD loan.
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
Unvested balance, weighted average grant date fair value (in dollars per share)
Unvested balance, weighted average grant date fair value (in dollars per share)
Note 12 - Fair Value - Unobservable Inputs (Details)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Forfeited, restricted awards (in shares)
Note 13 - Capital Stock - Outstanding Warrants (Details)
Note 14 - Net Loss Per Share - Computation of Basic and Diluted Net Income (Loss) Per Share (Details)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Unvested balance (in shares)
Unvested balance (in shares)
Foreign currency translation adjustments
Note 14 - Net Loss Per Share - Antidilutive Securities Excluded from Computation (Details)
Note 15 - Related Party Transactions - Revenue From 4Life Agreement (Details)
clnn_DebtConversionConversionPricePercentOf30dayTrailingVolumeweightedAverageSalePriceOfCommonStock
Debt Conversion, Conversion Price, Percent of 30-day Trailing Volume-weighted Average Sale Price of Common Stock
Represents conversion price of debt conversion into common stock as percentage of 30-day trailing volume-weighted average sale price of common stock.
Vested, exercisable or expected to vest, weighted average remaining term (Year)
Note 16 - Geographic and Segment Information - Profit and Loss Information by Reportable Segment (Details)
Note 16 - Geographic and Segment Information - Reconciliation of the Reportable Segments' Loss From Operations to Consolidated (Details)
Note 16 - Geographic and Segment Information - Assets by Reportable Segment (Details)
Note 16 - Geographic and Segment Information - Other Items from Segments by Reportable Segment (Details)
Notes To Financial Statements
clnn_DebtInstrumentMonthlyInterestonlyPaymentsMaximumAmountFirstEighteenInstallments
Debt Instrument, Monthly Interest-only Payments, Maximum Amount, First Eighteen Installments
Maximum amount of monthly interest-only payments for the first eighteen installments under debt instrument.
Vested, exercisable and expected to vest, number of options (in shares)
Notes To Financial Statements [Abstract]
clnn_DebtInstrumentMonthlyPrincipalAndInterestPaymentForTheNextThirtyInstallments
Debt Instrument, Monthly Principal and Interest Payment, for the Next Thirty Installments
Amount of monthly principal and interest payment for the next thirty installments under debt instrument.
Vested, exercisable and expected to vest, weighted average exercise price per share (in dollars per share)
The 2022 DHCD Loan [Member]
Represetns the 2022 DHCD loan.
Vested, exercisable or expected to vest, intrinsic value
Other comprehensive income (loss):
Vested and exercisable, weighted average exercise price per share (in dollars per share)
Vested and exercisable, weighted average remaining term (Year)
Vested and exercisable, intrinsic value
us-gaap_NotesPayableCurrent
Less notes payable, current portion, net of unamortized discount and debt issuance costs
Notes payable, current portion
Convertible notes payable, current portion
Less convertible notes payable, current portion, net of unamortized discount and debt issuance costs
Vested and exercisable, number of options (in shares)
Outstanding, weighted average remaining term (Year)
Outstanding, intrinsic value
Outstanding, intrinsic value
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)
Grant Funding Related to VISIONARY-MS Phase 2 Clinical Trial [Member]
Represents Grant Funding Related to VISIONARY-MS Phase 2 Clinical Trial.
National Multiple Sclerosis Society [Member]
Represents National Multiple Sclerosis Society.
clnn_PhantomSharesForPotentialRepayment
Phantom Shares for Potential Repayment (in shares)
The number of phantom shares for potential repayment.
clnn_GovernmentAssistanceRepaymentAdditionalPercentageOfGrantFundingTrancheOne
Government Assistance, Repayment, Additional Percentage of Grant Funding, Tranche One
Represents additional payment of the grant as a percentage of the fund, tranche one.
Financial Instruments [Domain]
clnn_GovernmentAssistanceRepaymentCumulativeSalesTrancheOne
Government Assistance, Repayment, Cumulative Sales, Tranche One
Cumulative sales amount required to repay additional grant funding, tranche one.
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Beginning balance outstanding, weighted average exercise price per share (in dollars per share)
Ending balance outstanding, weighted average exercise price per share (in dollars per share)
clnn_GovernmentAssistanceRepaymentAdditionalPercentageOfGrantFundingTrancheTwo
Government Assistance, Repayment, Additional Percentage of Grant Funding, Tranche Two
Represents additional payment of the grant as a percentage of the fund, tranche two.
Forfeited, weighted average exercise price per share (in dollars per share)
Expired, weighted average exercise price per share (in dollars per share)
clnn_GovernmentAssistanceRepaymentPercentageOfGrantFundingUponFirstCommercialProductSale
Government Assistance, Repayment, Percentage of Grant Funding Upon First Commercial Product Sale
Represents repayment amount of the grant as a percentage of grant funding upon first commercial product sale.
Financial Instrument [Axis]
clnn_GovernmentAssistanceRepaymentMaximumPercentageOfGrantFundingWhenAllMilestonesAchieved
Government Assistance, Repayment, Maximum Percentage of Grant Funding When All Milestones Achieved
Represents additional payment of the grant as a percentage of the fund if all milestones are achieved.
clnn_GovernmentAssistanceAggregateRepaymentPercentageOfGrantFunding
Government Assistance, Aggregate Repayment, Percentage of Grant Funding
Represents aggregate amount of repayment of the grant as a percentage of the fund.
clnn_GovernmentAssistanceRepaymentPercentageOfGrantFundingUponClosing
Government Assistance, Repayment, Percentage of Grant Funding Upon Closing
Represents amount of repayment needed upon closing as a percentage of the grant funding.
Granted, weighted average exercise price per share (in dollars per share)
clnn_GovernmentAssistanceRepaymentAmountUponClosing
Government Assistance, Repayment Amount Upon Closing
Repayment amount of the grant needed upon closing.
clnn_GovernmentAssistanceRepaymentCumulativeSalesTrancheTwo
Government Assistance, Repayment, Cumulative Sales, Tranche Two
Cumulative sales amount required to repay additional grant funding, tranche two.
Accrued liabilities
Total accrued liabilities
clnn_GovernmentAssistanceRepaymentAdditionalPercentageOfGrantFundingTrancheThree
Government Assistance, Repayment, Additional Percentage of Grant Funding, Tranche Three
Represents additional payment of the grant as a percentage of the fund, tranche three.
clnn_GovernmentAssistanceRepaymentCumulativeSalesTrancheThree
Government Assistance, Repayment, Cumulative Sales, Tranche Three
Cumulative sales amount required to repay additional grant funding, tranche three.
Accounts payable
clnn_GovernmentAssistancePossibleLossPercentageOfGrantFunding
Government Assistance, Possible Loss, Percentage of Grant Funding
Represents possible loss between repayment amounts as a percentage of the grant funding.
clnn_GovernmentAssistancePossibleLossBetweenMinimumAndMaximumRepaymentAmounts
Government Assistance, Possible Loss Between Minimum and Maximum Repayment Amounts
Reflects the estimated amount of loss from minimum and maximum repayment amount.
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)
Beginning balance outstanding, number of options (in shares)
Ending balance outstanding, number of options (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod
Expired, number of options (in shares)
Accrued compensation and benefits
Other
us-gaap_OtherAccruedLiabilitiesCurrent
us-gaap_PolicyTextBlockAbstract
Accounting Policies
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)
ATM Facility [Member]
Represents ATM facility.
Notes Payable [Member]
Represents notes payable.
Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]
Current liabilities:
Product [Member]
Total assets
us-gaap_Assets
TOTAL ASSETS
Plan Name [Axis]
Plan Name [Domain]
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)
Cash, Cash Equivalent, and Marketable Security [Text Block]
Share-Based Payment Arrangement [Text Block]
us-gaap_LossContingencyEstimateOfPossibleLoss
Loss Contingency, Estimate of Possible Loss
Business Description and Basis of Presentation [Text Block]
Award Type [Domain]
Award Type [Axis]
Assets that Continue to be Recognized, Transferred Financial Assets and Other Financial Assets Managed Together [Table]
Loss Contingency, Nature [Domain]
Loss Contingency Nature [Axis]
Commitments and Contingencies Disclosure [Text Block]
clnn_IssuanceOfCommonStockAsPaymentOfDebt
Issuance of common stock as payment of outstanding indebtedness
The amount of adjustment for the issuance of common stock as payment of debt.
Derivative Instrument [Axis]
Derivative Contract [Domain]
Fair value
Convertible Notes Payable [Member]
Income tax expense
Income Tax Expense (Benefit)
Income tax benefit
Short-Term Debt, Type [Axis]
Short-Term Debt, Type [Domain]
us-gaap_DefinedContributionPlanCostRecognized
Defined Contribution Plan, Cost
clnn_NumberOfRealEstateLeases
Number of Real Estate Leases
Represents number of real estate lease.
Other segment items - General and administrative
General and administrative
General and Administrative Expense
clnn_LesseeOperatingLeaseOptionToExtendPeriod
Lessee, Operating Lease, Option To Extend Period (Year)
Represents option to extend period for lessee operating lease.
us-gaap_RestrictedCash
Restricted cash
us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeeAmount
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount
Reconciliation of cash, cash equivalents and restricted cash to the consolidated balance sheets:
us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent
us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch
Defined Contribution Plan, Employer Matching Contribution, Percent of Match
Insurance
Cash and cash equivalents
us-gaap_Cash
Cash and cash equivalents
Royalty [Member]
Personnel
us-gaap_LaborAndRelatedExpense
Legal
Amendment Flag
City Area Code
Use of Estimates, Policy [Policy Text Block]
New Accounting Pronouncements, Policy [Policy Text Block]
clnn_PurchaseAgreementCommencingPeriod
Purchase Agreement, Commencing Period (Month)
Commercing period for Purchase Agreement.
us-gaap_GainLossOnSaleOfPropertyPlantEquipment
Loss on disposal of property and equipment
Current Fiscal Year End Date
Document Fiscal Period Focus
Document Fiscal Year Focus
Document Period End Date
Entity File Number
clnn_PercentageOfCommonStockBeneficialOwnership
Percentage of Common Stock Beneficial Ownership
Represents percentage of common stock beneficial ownership.
Entity Emerging Growth Company
Document Type
Loss on extinguishment of notes payable
Gain (Loss) on Extinguishment of Debt
Loss on extinguishment of notes payable
Entity Small Business
Entity Shell Company
clnn_PurchaseAgreementSharesSellLimitation
Purchase Agreement, Shares Sell Limitation (in shares)
Represents limitation of shares sell during period for Purchase Agreement.
Document Information [Line Items]
Document Information [Table]
Entity Public Float
Entity Filer Category
Entity Current Reporting Status
Entity Voluntary Filers
Entity Well-known Seasoned Issuer
Award Timing MNPI Disclosure [Text Block]
ecd_AwardTmgMnpiCnsdrdFlag
Award Timing MNPI Considered [Flag]
Entity Tax Identification Number
Entity Central Index Key
Insider Trading Policies and Procedures [Line Items]
Entity Registrant Name
ecd_InsiderTrdPoliciesProcAdoptedFlag
Insider Trading Policies and Procedures Adopted [Flag]
Entity [Domain]
Legal Entity [Axis]
Entity Address, Address Line One
ecd_NonRule10b51ArrTrmntdFlag
Non-Rule 10b5-1 Arrangement Terminated [Flag]
Entity Address, City or Town
ecd_Rule10b51ArrTrmntdFlag
Rule 10b5-1 Arrangement Terminated [Flag]
ecd_Rule10b51ArrAdoptedFlag
Rule 10b5-1 Arrangement Adopted [Flag]
Entity Address, Postal Zip Code
Entity Address, State or Province
ecd_NonRule10b51ArrAdoptedFlag
Non-Rule 10b5-1 Arrangement Adopted [Flag]
Material Terms of Trading Arrangement [Text Block]
Convertible notes payable
Convertible notes payable
Amount of convertible note payable as of the balance sheet date, classified as noncurrent.
Entity Common Stock, Shares Outstanding
Trading Arrangements, by Individual [Table]
Change in fair value of Clene Nanomedicine contingent earn-out liability
Change in fair value of Clene Nanomedicine contingent earn-out liability
Amount of change in fair value of contingent earnout.
Change in fair value of Initial Stockholders contingent earn-out liability
Change in fair value of Initial Stockholders contingent earn-out liability
Amount of change in fair value of initial shareholders contingent earnout.
clnn_DebtInstrumentConvertibleMinimumIncrementOfPrincipalForExercise
Debt Instrument, Convertible, Minimum Increment of Principal for Exercise
The minimum increment of principal the conversion feature may be exercised in for convertible debt instrument.
Finance and accounting
Public and investor relations
Trading Symbol
Information technology
Local Phone Number
us-gaap_TableTextBlock
Notes Tables
Related Party Transaction [Axis]
Related Party Transaction [Domain]
Research and development
Research and development
Research and Development Expense
Total interest expense on notes payable and convertible notes payable
Total interest expense on notes payable
us-gaap_DisclosureTextBlockAbstract
Notes to Financial Statements
Reverse Stock Split [Member]
The reverse stock split
Subsequent Event [Member]
Subawards [Member]
Represents the subawards for the NIH grant.
Restricted cash
Subsequent Event [Table]
Subsequent Event Type [Axis]
Subsequent Event Type [Domain]
Defined Benefit Plan [Table]
Reverse Stock Split [Policy Text Block]
Disclosure representing the reverse stock split.
Subsequent Events [Text Block]
us-gaap_UnamortizedDebtIssuanceExpense
Unamortized discount and debt issuance costs
Personnel
Prepaid clinical and CRO expenses
The amount of clinical and CRO expenses that have been prepaid
Fair Value of Financial Instruments, Policy [Policy Text Block]
Segment Reporting, Policy [Policy Text Block]
Foreign Currency Transactions and Translations Policy [Policy Text Block]
Lessee, Leases [Policy Text Block]
Earnings Per Share, Policy [Policy Text Block]
Total revenue
Revenue
Comprehensive Income, Policy [Policy Text Block]
Income Tax, Policy [Policy Text Block]
us-gaap_LesseeOperatingLeaseTermOfContract
Lessee, Operating Lease, Term of Contract (Year)
us-gaap_LesseeOperatingLeaseRenewalTerm
Lessee, Operating Lease, Renewal Term (Year)
Research and Development Expense, Policy [Policy Text Block]
NIH Grant Total [Member]
The total amount in the NIH grant.
us-gaap_StockholdersEquityNoteStockSplitConversionRatio1
Stockholders' Equity Note, Stock Split, Conversion Ratio
us-gaap_AssetsCurrent
Total current assets
Share-Based Payment Arrangement [Policy Text Block]
Equity [Text Block]
Other segment items - Research and development
Revenue from Contract with Customer [Policy Text Block]
us-gaap_DeferredTaxAssetsValuationAllowance
Less: valuation allowance
us-gaap_DeferredOfferingCosts
Deferred Offering Costs
Other
us-gaap_OtherAssetsCurrent
Avenue Warrants 2023 [Member]
Represents information pertaining to the 2023 avenue warrants.
Deferred Charges, Policy [Policy Text Block]
Debt, Policy [Policy Text Block]
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]
Derivatives Other Than Common Stock Warrants Liabilities [Member]
Represents derivatives other than common stock warrant liabilities.
clnn_NoncashInterestIncomeExpenseOnMarketableSecurities
Non-cash interest income on marketable securities
Represents the amount of noncash interest income (expense) on marketable securities.
Metals to be used in research and development
us-gaap_DeferredIncomeTaxLiabilities
Total deferred tax liabilities
Inventory
Grant Funding Related to REPAIR-MS Phase 2 Clinical Trial [Member]
Relating to grant funding related to REPAIR-MS Phase 2 Clinical Trial.
clnn_NoncashInterestIncomeExpenseOnNotesPayable
Non-cash interest expense on notes payable
Represents the amount of interest income (expense) on notes payable.
us-gaap_InventoryFinishedGoods
Inventory, Finished Goods, Gross
Segment, Reconciliation of Other Items from Segments to Consolidated [Table Text Block]
Certain Directors, Executive Officers, and Affiliated Entities [Member]
Represents information pertaining to certain directors, executive officers, and affiliated entities.
Reconciliation of Assets from Segment to Consolidated [Table Text Block]
Depreciation and amortization
Reconciliation of Revenue from Segments to Consolidated [Table Text Block]
us-gaap_InventoryRawMaterials
Inventory, Raw Materials, Gross
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]
Capitalized research and development expenses
Lincoln Park Capital Fund, LLC [Member]
Relating to Lincoln Park Capital Fund, LLC.
us-gaap_PropertyPlantAndEquipmentUsefulLife
Property, Plant and Equipment, Useful Life (Year)
Construction in Progress [Member]
Cashless exercise of pre-funded warrants (in shares)
Exercise of pre-funded warrants (in shares)
Number of shares issued during the period as a result of warrants exercised.
Cashless exercise of pre-funded warrants
Exercise of pre-funded warrants
Value of stock issued as a result of the exercise of warrants.
Common Stock Warrant Liability [Member]
Represents the common stock warrant liability.
Schedule of Segment Reporting Information, by Segment [Table]
Clene Nanomedicine Contingent Earn-out [Member]
Represents Clene Nanomedicine contingent earn-out.
The 2024 S S C P Notes [Member]
Represents the 2024 SSCP notes.
Proceeds from the issuance of debt and derivative liabilities
The cash inflow provided by issuance of debt and derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.
Initial Stockholders Contingent Earn-out [Member]
Represents Initial Stockholders contingent earn-out.
Furniture and Fixtures [Member]
Accounts receivable
us-gaap_CashCashEquivalentsAndShortTermInvestments
Cash, Cash Equivalents, and Short-Term Investments
Non-qualified stock options and restricted stock awards
Accrued compensation
Revenue:
Leasehold Improvements [Member]
Property, Plant and Equipment, Policy [Policy Text Block]
Property, Plant and Equipment [Table]
Other expense, net
Long-Lived Tangible Asset [Axis]
Total other income (expense), net
us-gaap_NonoperatingIncomeExpense
Total other income (expense), net
Segment Reporting Disclosure [Text Block]
Long-Lived Tangible Asset [Domain]
Net operating loss carryforwards
Statutory Accounting Practices [Table]
Research and development and employment tax credits
Current assets:
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
Cash, cash equivalents and restricted cash
Regulated Operation, Regulatory Liability [Table]
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations
Cash, cash equivalents and restricted cash – beginning of period
Cash, cash equivalents and restricted cash – end of period
Inventory, Policy [Policy Text Block]
Private Placement [Member]
Interest income
Effect of foreign exchange rate changes on cash and restricted cash
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
Net decrease in cash, cash equivalents and restricted cash
us-gaap_NetCashProvidedByUsedInFinancingActivities
Net cash provided by (used in) financing activities
Sale of Stock [Axis]
Sale of Stock [Domain]
Segment loss from operations
Segment loss from operations
Operating Income (Loss)
Loss from operations
us-gaap_NetCashProvidedByUsedInOperatingActivities
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation
Net cash used in operating activities
Other income (expense), net:
us-gaap_DeferredTaxLiabilitiesOther
Other
us-gaap_NetCashProvidedByUsedInInvestingActivities
Net cash provided by (used in) investing activities
us-gaap_DeferredTaxLiabilities
Net deferred tax assets (liabilities)
Debt Registration Fee [Member]
Represents debt registration fee.
Cost of revenue
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]
clnn_DebtInstrumentFinalPayment
Debt Instrument, Final Payment
Amount of final payment under debt instrument.
clnn_DebtInstrumentFinalPaymentPercentageOfFundedPrincipal
Debt Instrument, Final Payment, Percentage of Funded Principal
Amount of final payment as percentage of funded principal under debt instrument.
us-gaap_DeferredTaxLiabilitiesLeasingArrangements
Right-of-use asset
clnn_DebtInstrumentCashPaymentInTheEventOfChangeInControlOrRestructuringProcessPercentageOfPrincipalOustanding
Debt Instrument, Cash Payment in the Event of Change in Control or Restructuring Process, Percentage Of Principal Outstanding
Amount of cash payment under debt instrument in the event of change in control or restructuring process as percentage of principal outstanding.
clnn_DebtInstrumentConvertibleMaximumConversionAmountPercentageOfPrincipalOustanding
Debt Instrument, Convertible, Maximum Conversion Amount, Percentage of Principal Oustanding
Maximum amount of principal that can be converted under the debt instrument as percentage of principal outstanding.
Derivative Instrument Related to Senior Secured Convertible Promissory Notes [Member]
Represents Derivative Instrument Related to Senior Secured Convertible Promissory Notes.
Maintenance
Reverse Recapitalization [Member]
Represents Reverse Recapitalization.
clnn_DebtInstrumentEarlyTerminationFeePercentageOfOutstandingPrincipal
Debt Instrument, Early Termination Fee, Percentage of Outstanding Principal
Amount of early termination fee as percentage of principal outstanding under debt instrument.
clnn_DebtInstrumentCollateralDeficiencyFeePercentage
Debt Instrument, Collateral Deficiency Fee, Percentage
Amount of collateral deficiency fee as percentage under debt instrument.
Concentration Risk, Credit Risk, Policy [Policy Text Block]
Warrants Issued with 2021 Avenue Loan [Member]
Represents warrants issued with 2021 Avenue Loan.
clnn_DebtInstrumentAggregateRegistrationFeePenaltyAmountMaximumPercentageOfFaceValueOfDebt
Debt Instrument, Aggregate Registration Fee Penalty Amount, Maximum Percentage of Face Value of Debt
Maximum aggregate registration fee penalty amount allowed under debt instrument as percentage of face value of debt.
clnn_DebtInstrumentRegistrationFeePenaltyAmountPercentageOfFaceValueOfDebt
Debt Instrument, Registration Fee Penalty Amount, Percentage of Face Value of Debt
Amount of penalty as percentage of face value of debt under debt instrument.
Manufacturing
Research and development tax credits receivable
Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from research and development tax credits receivable.
Restricted Stock and Restricted Stock Unit [Member]
Represents Restricted Stock and Restricted Stock Unit.
Warrants Originally Issued by Tottenham Acquisition I Limited [Member]
Represents warrants originally issued by Tottenham Acquisition I Limited.
Convertible Notes [Policy Text Block]
Disclosure of accounting policy for convertible notes.
Placement Agency Agreement [Member]
Represents Placement Agency Agreement.
Contingent Earnout [Policy Text Block]
Disclosure for accounting policy for contingent earnout.
clnn_FairValueOfEquityIssuedExceedingOfferingProceedsAmount
Fair Value of Equity Issued Over Offering Proceeds
Amount of values of fair value of equity issued are over offering proceeds value.
Common Stock Warrants [Policy Text Block]
Disclosure of accounting policy for common stock warrants.
clnn_EquityAgentFeePercentageOfAggregateGrossProceedsOfTheOffering
Equity Agent Fee, Percentage of Aggregate Gross Proceeds of the Offering
Amount of equity issuance agent fee as percentage of aggregate gross proceeds of the offering.
Grant Funding on Conditional Grants [Member]
Represents grant funding on conditional grants.
us-gaap_CostsAndExpenses
Total operating expenses
The 2024 Pre-funded Warrants [Member]
Represents the 2024 prefunded warrants.
The 2024 Common Warrants [Member]
Represents the 2024 common warrants.
Risk and Uncertainties [Policy Text Block]
Disclosure of accounting policy for risks and uncertainties.
us-gaap_ProceedsFromIssuanceOrSaleOfEquity
Proceeds from Issuance or Sale of Equity
Common Warrant Exercisable on October 2024 [Member]
Represents Common Warrant Exercisable on October 2024.
Operating expenses:
Facilities
The aggregate costs of facilities.
Clinical Trial Accrual [Policy Text Block]
Disclosure of accounting policy for clinical trial accrual.
The 2024 Pre-funded Warrants in Connection With Private Placements [Member]
Represents The 2024 Pre-funded Warrants in Connection With Private Placements.
The 2024 Pre-funded Warrants in Connection With Placement Agency Agreement [Member]
Represents The 2024 Pre-funded Warrants in Connection With Placement Agency Agreement.
Equipment
us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense
Placement Agency Agreement and Private Placement [Member]
Represents placement agency agreement and private placement.
Chardan Unit Purchase Option [Member]
Represents Chardan Unit Purchase Option.
Proceeds from exercise of stock options
us-gaap_ProceedsFromIssuanceOfCommonStock
Proceeds from Issuance of Common Stock
Restricted Stock Awards [Member]
Represents restricted stock awards.
The 2024 S S C P Note [Member]
Represents the 2024 senior secured promissory note.
clnn_NumberOfWarrantsPerUnit
Number of Warrants Per Unit (in shares)
Number of warrants issued or issuable for each unit.
clnn_NumberOfSharesPerUnitIssued
Number of Shares Per Unit Issued (in shares)
Number of shares of stock issued or issuable for each unit.
clnn_BusinessCombinationContingentEarnoutMilestoneTwoPeriod
Business Combination, Contingent Earnout, Milestone Two, Period (Year)
The period for milestone two of contingent earnout in business combination.
Foreign
us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Net loss before income taxes
United States
Prepaid Expenses and Other Current Assets [Text Block]
The entire disclosure for prepaid expenses and other current assets.
ICFR Auditor Attestation Flag
Lessee, Operating and Finance Leases [Text Block]
The entire disclosure for operating and finance leases of lessee. Includes, but is not limited to, description of operating and finance lease and maturity analysis of operating and finance lease liability.
Lease for Laboratory Space [Member]
Represents lease for laboratory space.
State and Local Jurisdiction [Member]
Income Tax Jurisdiction [Axis]
Income Tax Jurisdiction [Domain]
Domestic Tax Jurisdiction [Member]
Schedule of Cash Flow, Supplemental Disclosures, Leases [Table Text Block]
Tabular disclosure of supplemental cash flow information related to leases for the periods presented.
The 2019 MD Loan [Member]
Represents the 2019 MD Loan.
Finance and Operating Lease Liability, Maturity [Table Text Block]
Tabular disclosure of undiscounted cash flows of finance and operating lease liability. Includes, but is not limited to, reconciliation of undiscounted cash flows to finance and operating lease liability recognized in statement of financial position.
Accounts Receivable [Policy Text Block]
Cash and Cash Equivalents, Policy [Policy Text Block]
Department of Housing and Community Development [Member]
Represents Department of Housing and Community Development.
The 2019 Cecil Loan [Member]
Represents the 2019 Cecil Loan.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]
Advance Cecil Inc. [Member]
Represents Advance Cecil Inc.
Notes Payable, Tranche 2 [Member]
Represents Tranche 2 of notes payable.
us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]
Basis of Accounting, Policy [Policy Text Block]
clnn_DebtInstrumentInterestOnlyPaymentsPeriod
Debt Instrument, Interest Only Payments, Period (Month)
Period of interest only payments under debt instrument.
The 2021 Avenue Loan [Member]
Represents the 2021 Avenue Loan.
Avenue [Member]
Represents Avenue.
Notes Payable, Tranche 1 [Member]
Represents tranche 1 of notes payable.
Related Party [Member]
clnn_DebtInstrumentCovenantCashAndCertainCashEquivalentsMinimum
Debt Instrument, Covenant, Cash and Certain Cash Equivalents, Minimum
Requirement for cash and certain cash equivalents under the debt agreement.
Research and development tax credits and unrestricted grants
Government Assistance, Amount
clnn_DebtInstrumentFirstInterestonlyPeriodExtension
Debt Instrument, First Interest-only Period Extension (Month)
The first interest-only period extension under the debt instrument.
clnn_DebtInstrumentConvertibleMaximumConversionAmount
Debt Instrument, Convertible, Maximum Conversion Amount
Maximum amount of principal that can be converted under the debt instrument.
us-gaap_ProceedsFromConvertibleDebt
Proceeds from Convertible Debt
Government Assistance, Type [Axis]
Government Assistance, Type [Domain]
Government Assistance [Policy Text Block]
clnn_ClassOfWarrantOrRightExercisedDuringPeriod
Class of Warrant or Right, Exercised During Period (in shares)
The number of warrants or rights exercised during period.
Addition to Long-Lived Assets
us-gaap_SegmentExpenditureAdditionToLongLivedAssets
Auditor Name
clnn_PurchaseAgreementAdditionalCommitmentShares
Purchase Agreement, Additional Commitment Shares (in shares)
Additional commitment shares for purchase agreement.
Income Tax Contingency [Table]
clnn_PurchaseAgreementMinimumAveragePricePerShareToAvoidSellLimitation
Purchase Agreement, Minimum Average Price Per Share To Avoid Sell Limitation (in dollars per share)
Minimum average price per share to avoid sell limitation for purchase agreement.
Common Stock Warrant Exercisable on December 2020, One [Member]
Represents the common stock warrant exercisable on December 2020.
clnn_PurchaseAgreementSharesSellLimitationPercentageOfOutstandingShares
Purchase Agreement, Shares Sell Limitation, Percentage Of Outstanding Shares
Percentage of outstanding shares for shares sell libation for purchase agreement.
Common Stock Warrant Exercisable on December 2020, Two [Member]
represents the common stock warrant exercisable on December 2020.
Auditor Firm ID
Auditor Location
us-gaap_TaxCreditCarryforwardAmount
Tax Credit Carryforward, Amount
clnn_PurchaseAgreementAmountOfSharesCommitToPurchase
Purchase Agreement, Amount Of Shares Commit To Purchase
Represents amount of shares commit to purchase for purchase agreement.
clnn_DebtIssuanceCostsExpensed
Debt Issuance Costs Expensed
Represents debt issuance costs expensed.
us-gaap_RepaymentsOfNotesPayable
Payments of notes payable
Research Tax Credit Carryforward [Member]
Change in fair value of contingent earn-outs
Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to change in fair value of derivative for contingent earn-out.
Antidilutive securities (in shares)
Lease liability
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from lease liability.
us-gaap_ProceedsFromNotesPayable
Proceeds from Notes Payable, Total
clnn_OperatingLossCarryforwardsSubjectToExpiration
Operating Loss Carryforwards Subject to Expiration
Amount of operating loss carryforwards that are subject to expiration.
clnn_OperatingLossCarryforwardsNotSubjectToExpiration
Operating Loss Carryforwards Not Subject to Expiration
Amount of operating loss carryforwards that are not subject to expiration dates.
Tax Credit Carryforward [Axis]
Tax Credit Carryforward, Name [Domain]
Change in fair value of common stock warrant liabilities
Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to change in fair value of derivative of common stock warrant.
us-gaap_OperatingLossCarryforwards
Operating Loss Carryforwards
clnn_DeferredTaxAssetsLiabilityGross
Total deferred tax assets
Amount before allocation of valuation allowances of deferred tax asset (liability) attributable to deductible temporary differences and carryforwards.
The 2020 Stock Plan [Member]
Represents the 2020 Stock Plan.
Statement of Financial Position [Abstract]
The 2014 Stock Plan [Member]
Represents 2014 Stock Plan.
Granted, weighted average remaining term (Year)
Weighted average remaining contractual term for option awards granted in period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
Weighted average common shares used to compute basic and diluted net loss per share (in shares)
Stock-based compensation, percent
Other, tax adjustments, percent
us-gaap_EffectiveIncomeTaxRateContinuingOperations
Effective Income Tax Rate Reconciliation, Percent
Income tax benefit, percent
Business Combination [Axis]
Net loss per share – basic and diluted (in dollars per share)
Business Combination [Domain]
The 401(k) Plan [Member]
Represents the 401(k) plan.
Changes in valuation allowances, percent
Contingent Earnout Shares [Member]
Represents contingent earnout shares.
Statement of Cash Flows [Abstract]
Lease Contractual Term [Domain]
Statement of Stockholders' Equity [Abstract]
Lease Contractual Term [Axis]
Schedule of Accrued Liabilities [Table Text Block]
us-gaap_RepaymentsOfDebt
Repayments of Debt
Supply Agreement [Member]
Represents supply agreement.
clnn_RelatedPartyTransactionRoyaltyFeeRateForRevenues
Related Party Transaction, Royalty Fee Rate for Revenues
Percentage of royalty fee for revenues in related party transaction.
Common Stock Warrants [Member]
Represents common stock warrants.
4Life [Member]
Represents 4Life.
Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]
Finance lease amortization
clnn_DebtInstrumentUnfundedBalance
Debt Instrument, Unfunded Balance
Amount of debt instrument that has not yet been funded.
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
State and local income tax effects(1), percent
Foreign tax effects, percent
us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsResearch
Research and development credits - Federal, percent
Other, tax adjustments
Cash flows from financing activities:
U.S. Federal statutory tax rate, percent
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]
Adjustment for change in tax rate
Changes in valuation allowances
Stock-based compensation
Segment Reporting, Reconciling Item, Corporate Nonsegment [Member]
Non-cash lease expense
Property and equipment, net
Total property and equipment, net
us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization
Less accumulated depreciation
Class of Stock [Axis]
Property and equipment, gross
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
State and local income tax effects(1)
Foreign tax effects
us-gaap_IncomeTaxReconciliationTaxCreditsResearch
Research and development credits - Federal
us-gaap_DerivativeNotionalAmount
Derivative, Notional Amount
U.S. Federal statutory tax rate
Income Tax Disclosure [Text Block]
Schedule of Maturities of Long-Term Debt [Table Text Block]
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Share-Based Payment Arrangement, Option, Activity [Table Text Block]
Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]
Proceeds from maturities of marketable securities
Share-Based Payment Arrangement, Cost by Plan [Table Text Block]
us-gaap_PaymentsToAcquireMarketableSecurities
Purchases of marketable securities
Retirement Plan Name [Axis]
Retirement Plan Name [Domain]
Equity Distribution Agreement [Member]
Represents the equity distribution agreement.
Stock issued
Stock issued
us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Purchases of property and equipment
us-gaap_IncreaseDecreaseInOperatingLeaseLiability
Operating lease obligations
Supplemental cash flow information:
Business Combination, Consideration Transferred, Equity Interest, Type [Axis]
Business Combination, Consideration Transferred, Equity Interest, Type [Domain]
Effective Income Tax Rate Reconciliation [Table]
Net loss
Net loss
Restricted Stock [Member]
Share-Based Payment Arrangement, Option [Member]
Coupon interest
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]
Antidilutive Security, Excluded EPS Calculation [Table]
Antidilutive Securities [Axis]
Antidilutive Securities, Name [Domain]
Senior Secured Convertible Promissory Notes [Member]
Related to senior secured convertible promissory notes.
Long-Term Debt, Type [Axis]
Amended 2024 SSCP Notes [Member]
Related to Amended 2024 SSCP Notes.
us-gaap_GovernmentAssistanceAwardAmount
Government Assistance, Award Amount
Long-Term Debt, Type [Domain]
Capital Addition Purchase Commitments [Member]
Deferred grants
Cash flows from investing activities:
Issuance costs for common stock warrant liabilities
Issuance costs for common stock warrant liabilities
Amount of costs for issuance of common stock warrant liability.
Proceeds from issuance of common stock, warrants, and pre-funded warrants, net of offering costs
The cash inflow from issuance of common stock and warrants, net of issuance costs.
Earnings Per Share [Text Block]
New Avenue Warrant [Member]
Represents new avenue warrant.
us-gaap_RelatedPartyTransactionRate
Related Party Transaction, Rate
Common stock warrant liability recorded upon public stock offering
Noncash amount of common stock warrant liability recorded upon public stock offering.
Related Party Transaction [Table]
us-gaap_DeferredFinanceCostsGross
Debt Issuance Costs, Gross
Public Equity Offering [Member]
Represents public equity offering.
Related Party Transactions Disclosure [Text Block]
Schedule of Related Party Transactions [Table Text Block]
us-gaap_IncreaseDecreaseInAccruedLiabilities
Accrued liabilities
Tranche B Warrant [Member]
Represents tranche B warrant.
Measurement Input, Probability of Fundamental Transaction [Member]
Represents probability of fundamental transaction.
Tranche A Warrant [Member]
Represents tranche A warrant.
Measurement Input, Probability of Change of Control [Member]
Represents probability of change of control.
us-gaap_IncreaseDecreaseInAccountsPayable
Accounts payable
Measurement Input, Probability of NDA Acceptance [Member]
Represents probability of NDA acceptance.
clnn_UnitIssuedPricePerUnit
Unit Issued, Price Per Unit (in dollars per share)
Per share or per unit amount of units issued.
Common Stock Warrant Exercisable on June 2023, Three [Member]
Represents common stock warrant exercisable on June 2023, three.
Common Stock Warrant Exercisable on June 2023, Two [Member]
Represents common stock warrant exercisable on June 2023, two.
Common Stock Warrant Exercisable on June 2023, One [Member]
Represents common stock warrant exercisable on June 2023, one.
us-gaap_InterestExpenseNonoperating
Interest expense
us-gaap_DebtInstrumentConvertibleConversionPrice1
Debt Instrument, Convertible, Conversion Price (in dollars per share)
Total stock-based compensation expense
Share-Based Payment Arrangement, Expense
Change in fair value pursuant to the 2024 SSCPN Amendment, recorded as a debt discount
Change in fair value
us-gaap_ComprehensiveIncomeNetOfTax
Comprehensive loss
us-gaap_DebtInstrumentPeriodicPaymentPrincipal
Debt Instrument, Periodic Payment, Principal
us-gaap_SharesOutstanding
Balances (in shares)
Balances (in shares)
Common stock, shares outstanding (in shares)
Common Stock, Shares, Outstanding (in shares)
us-gaap_PreferredStockSharesOutstanding
Preferred Stock, Shares Outstanding (in shares)
us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Debt Instrument, Basis Spread on Variable Rate
Interest Rate
Debt Instrument, Interest Rate, Stated Percentage
Variable lease costs
us-gaap_LeaseCost
Total lease costs
us-gaap_DebtInstrumentInterestRateEffectivePercentage
Debt Instrument, Interest Rate, Effective Percentage
us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets
Prepaid expenses and other current assets
us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent
Operating Lease, Weighted Average Discount Rate, Percent
us-gaap_DebtInstrumentFairValue
Debt Instrument, Fair Value Disclosure
Operating lease costs
Short-term lease costs
Lease, Cost [Table Text Block]
us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1
Operating Lease, Weighted Average Remaining Lease Term (Year)
us-gaap_DebtInstrumentFaceAmount
Debt Instrument, Face Amount
Interim Period, Costs Not Allocable [Domain]
Capitalization, Equity [Table]
Nature of Expense [Axis]
us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue
Balance
Balance
Issuance of stock options as payment of bonus liability
Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock as payments of bonus liability.
Debt Instrument [Axis]
Debt Instrument, Name [Domain]
Payment of Bonus Liability [Member]
Payment of Bonus Liability
Payment of Outstanding Indebtedness [Member]
Payment of Outstanding Indebtedness
us-gaap_AdjustmentsToAdditionalPaidInCapitalStockSplit
Adjustments to Additional Paid in Capital, Stock Split
Schedule of Long-Term Debt Instruments [Table Text Block]
Schedule of Long-Term Debt Instruments [Table]
Issuance of equity-classified pre-funded warrants
us-gaap_IncreaseDecreaseInAccountsReceivable
Accounts receivable
Stock-based compensation expense
Expired, weighted average grant date fair value
Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.
clnn_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriod
Expired, restricted awards (in shares)
The number of equity-based payment instruments, excluding stock (or unit) options, that were expired during the reporting period.
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
January 2026 Public Equity Offering [Member]
January 2026 Public Equity Offering
Measurement Input, Probability of Held-to-maturity [Member]
Measurement Input, Probability of Held-to-maturity
Common Stock Warrant Exercisable on October 2024, Two [Member]
Common Stock Warrant Exercisable on October 2024, Two
Measurement Input, Probability of Held to Expiration [Member]
Measurement Input, Probability of Held to Expiration
Deferred Employee Compensation [Member]
Deferred Employee Compensation
clnn_PolicyTable
us-gaap_IncreaseDecreaseInInventories
Inventory
Exercise of stock options (in shares)
Issuance of common stock upon vesting of restricted stock awards (in shares)
Exercise of stock options
Issuance of common stock upon vesting of restricted stock awards
Related and Nonrelated Parties [Axis]
Related and Nonrelated Parties [Domain]
Granted, number of options (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod
Forfeited, number of options (in shares)
us-gaap_WarrantsAndRightsOutstandingTerm
Warrants and Rights Outstanding, Term (Year)
Line of Credit Facility, Lender [Domain]
Issuance of common stock (in shares)
Stock Issued During Period, Shares, New Issues (in shares)
Lender Name [Axis]
us-gaap_LiabilitiesAndStockholdersEquity
TOTAL LIABILITIES AND STOCKHOLDERS’ DEFICIT
Unlikely to Vest Options [Member]
Relating to unlikely to vest options.
clnn_GovernmentAssistanceCashReceipt
Government Assistance, Cash Receipt
Represents the amount of cash receipts from government assistance during the period.
Issuance of common stock
Derivative, measurement input
Accumulated deficit
Retained Earnings (Accumulated Deficit)
Accumulated other comprehensive income
Cash Equivalents [Member]
Money Market Funds [Member]
Measurement Input, Discount Rate [Member]
Debt Disclosure [Text Block]
Cash and Cash Equivalents [Axis]
Cash and Cash Equivalents [Domain]
Cash [Member]
Measurement Input, Price Volatility [Member]
Changes in operating assets and liabilities:
Measurement Input, Risk Free Interest Rate [Member]
Restrictions on Cash and Cash Equivalents [Table]
Schedule of Cash and Cash Equivalents [Table Text Block]
Lease obligations, net of current portion
Operating lease obligations, net of current portion
Measurement Input, Expected Dividend Rate [Member]
Measurement Input, Expected Term [Member]
Present value of minimum lease payments
us-gaap_OperatingLeaseLiability
Cash and Cash Equivalents [Member]
Operating lease obligations, current portion
Less lease obligations, current portion
Operating lease right-of-use assets
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue
Total minimum lease payments
us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount
Less amount representing interest/discounting
us-gaap_FinanceLeasePrincipalPayments
Payments of finance lease obligations
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree
2028
Measurement Input Type [Axis]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour
2029
Measurement Input Type [Domain]
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive
2030
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive
Thereafter
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths
2026
us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo
2027
us-gaap_FairValueAdjustmentOfWarrants
Change in fair value of common stock warrant liabilities
Change in fair value of common stock warrant liabilities
us-gaap_ShareBasedCompensation
Stock-based compensation expense
Amortization of debt discount and issuance costs
Amortization of Debt Issuance Costs and Discounts
Accretion of debt discount
Measurement Input, Probability of Dissolution [Member]
Related to the probability of dissolution.
Depreciation
clnn_EquityMilestone1ConditionForExtendedInterestOnlyPeriod
Equity Milestone 1 Condition for Extended Interest Only Period
The equity milestone 1 condition for extended interest only period.
Cash Equivalents
Change in fair value of derivative liabilities
Change in fair value of derivative liabilities
Fair Value Measurement Inputs and Valuation Techniques [Table]
Common stock, $0.0001 par value: 600,000,000 shares authorized; 10,849,974 and 8,089,565 shares issued and outstanding at December 31, 2025 and December 31, 2024, respectively
Adjustments to reconcile net loss to net cash used in operating activities:
Common stock, shares authorized (in shares)
Common Stock, Shares Authorized (in shares)
us-gaap_TangibleAssetImpairmentCharges
Tangible Asset Impairment Charges
Common stock, shares issued (in shares)
Common Stock, Shares, Issued (in shares)
Common stock, par value (in dollars per share)
Common Stock, Par or Stated Value Per Share (in dollars per share)
us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
Common Stock, Capital Shares Reserved for Future Issuance (in shares)
Statistical Measurement [Domain]
Lessee, Lease, Description [Table]
us-gaap_OperatingLeasePayments
Operating cash flows from operating leases
Maximum [Member]
Supplemental disclosure of non-cash investing and financing activities:
Minimum [Member]
Product and Service [Axis]
Product and Service [Domain]
Statistical Measurement [Axis]
us-gaap_PaymentsForCommissions
Payments for Commissions
us-gaap_PreferredStockSharesIssued
Preferred Stock, Shares Issued (in shares)
License Agreement [Member]
In reference to the License Agreement.
Cash paid for interest expense
Property, Plant and Equipment Disclosure [Text Block]
Property, Plant and Equipment [Table Text Block]
us-gaap_PreferredStockSharesAuthorized
Preferred Stock, Shares Authorized (in shares)
us-gaap_PreferredStockParOrStatedValuePerShare
Preferred Stock, Par or Stated Value Per Share (in dollars per share)
us-gaap_ProceedsFromLoans
Proceeds from Loans
Fair Value, Inputs, Level 3 [Member]
Fair Value Hierarchy and NAV [Domain]
Fair Value, Inputs, Level 1 [Member]
Derivative liability recorded upon debt issuance
The amount of derivative liability recorded upon debt issuance.
Fair Value, Inputs, Level 2 [Member]
Derivative liability recorded upon debt modification
The derivative liability recorded upon debt modification.
Fair Value Hierarchy and NAV [Axis]
Cash flows from operating activities:
us-gaap_WarrantsAndRightsOutstanding
Warrants and Rights Outstanding
Statement [Line Items]
Additional paid-in capital
The 2025 S S C P Notes [Member]
Represents the 2025 SSCP notes.
clnn_DebtInstrumentConvertibleMaximumConversionAmountAmountOfPrincipalOutstanding
Debt Instrument, Convertible, Maximum Conversion Amount, Amount of Principal Outstanding
The maximum conversion amount of the outstanding principle on the convertible debt.
clnn_DebtInstrumentConvertibleAccruedInterestConversion
Debt Instrument, Convertible, Accrued Interest Conversion (in dollars per share)
The conversion rate of accrued interest on the convertible debt.
AOCI Attributable to Parent [Member]
Stockholders’ deficit:
The 2025 S S C P Note [Member]
Represents the 2025 SSCP note.
The 2024 and 2025 S S C P Notes [Member]
Represents the 2024 and 2025 SSCP notes.
Fair Value Disclosures [Text Block]
us-gaap_Liabilities
TOTAL LIABILITIES
Commitments and contingencies (Note 9)
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]
Prepaid expenses and other current assets
Total prepaid expenses and other current assets
Counterparty Name [Axis]
Counterparty Name [Domain]
clnn_RelatedPartyTransactionExclusiveSupplyTerm
Related Party Transaction, Exclusive Supply Term (Year)
Represents the exclusive supply term with a related party.
Consolidation Items [Domain]
clnn_EffectiveIncomeTaxRateReconciliationGainLossOnInitialIssuanceOfEquityAmount
Loss on initial issuance of equity
Represents the loss on initial issuance of equity.
Derivative liabilities
us-gaap_DerivativeLiabilities
Derivative Liability
Consolidation Items [Axis]
us-gaap_InterestPayableCurrentAndNoncurrent
Interest Payable
us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued
Retained Earnings [Member]
Additional Paid-in Capital [Member]
Common Stock [Member]
Series B Warrants [Member]
Relating to Series B Warrants.
Equity Components [Axis]
Equity Component [Domain]
Series A Warrants [Member]
Relating to Series A Warrants.
us-gaap_LongTermDebt
Total debt principal payments
Exercise price (in dollars per share)
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)
Class of Warrant or Right [Axis]
Class of Warrant or Right [Domain]
us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)
Number of shares issuable (in shares)
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)
clnn_MinimumCashBalanceForLoanCovenant
Minimum Cash Balance For Loan Covenant
Minimum cash balance for loan covenant.
Depreciation Of Property Plant And Equipment [Table Text Block]
Tabular disclosure of depreciation of property plant and equipment.
Accrued CRO and clinical fees
Accrued CRO and clinical fees.
us-gaap_DeferredFinanceCostsNet
Debt Issuance Costs, Net
us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet
Unamortized discount and debt issuance costs
Office Equipment [Member]
Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member]
Equipment [Member]
Document Annual Report
Computer Equipment [Member]
us-gaap_DebtInstrumentUnamortizedDiscountPremiumNet
Unamortized discount and debt issuance costs
Entity Incorporation, State or Country Code
Future debt payments, net
us-gaap_DebtInstrumentCarryingAmount
Long-Term Debt, Gross
General and Administrative Expense [Member]
Document Transition Report
Document Financial Statement Error Correction [Flag]
Entity Interactive Data Current
Security Exchange Name
Title of 12(b) Security
Research and Development Expense [Member]
Statement of Income Location, Balance [Axis]
Statement of Income Location, Balance [Domain]
Nonmonetary Transaction Type [Domain]
Nonmonetary Transaction Type [Axis]
Statement [Table]
Loss on initial issuance of equity
Loss on initial issuance of equity
The amount of gain (loss) on issuance of equity.
Income Statement [Abstract]
us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
Total other comprehensive income (loss)
2028
2029
2030
Thereafter
2026
2027
Initial fair value of instruments issued
This value for initial fair value of instrument.
CNM-ZnAg [Member]
Related to CNM-ZnAg.
Accounting Standards Update and Change in Accounting Principle [Table]
clnn_ResearchAndDevelopmentExpenseOther
Research
Amount of expense for research and development not specifically disclosed. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.
CNM-Au8, Amyotrophic Lateral Sclerosis [Member]
Related to product costs.
Grant revenue as a reduction of research and development expense
The amount of grant revenue, net of a reduction of research and development expense.
CNM-Au8, Regulatory Activities [Member]
Related to product costs.
CNM-Au8, Multiple Sclerosis [Member]
Related to product costs.
CNM-Au8, Parkinson's Disease [Member]
Related to product costs.
Other Commitments [Table]
clnn_ResearchAndDevelopmentExpenseIncome
Research and development
The amount of research and development expense (income) during the period.
General, Preclinical, Nonclinical [Member]
Related to services.
Derivative liabilities
Accrued and unpaid interest
Accrued and unpaid interest.
us-gaap_StockholdersEquity
TOTAL STOCKHOLDERS’ DEFICIT
Balances
Balances
The 2019 Maryland DHCD [Member]
Represents the 2019 Maryland DHCD
The 2022 Maryland DHCD [Member]
Represents the 2022 Maryland DHCD
us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Gross unrealized losses
Gross unrealized gains
Notes payable, net of current portion
Operating Segments [Member]
Schedule of Interest Expense on Debt Instruments [Table Text Block]
Tabular disclosure of the interest expense for debt instruments.
Amortized cost
us-gaap_LongTermPurchaseCommitmentAmount
Long-Term Purchase Commitment, Amount