0001437749-23-006264 | 10-K | XBRL Viewer

Business Description and Basis of Presentation [Text Block]

Note 1. Nature of the Business

Clene Inc. (the “Company,” “we,” “us,” or similar such references) is a clinical-stage pharmaceutical company pioneering the discovery, development, and commercialization of novel clean-surfaced nanotechnology therapeutics. We have developed an electro-crystal-chemistry drug development platform which enables production of concentrated, stable, highly active, clean-surfaced nanocrystal suspensions. We have multiple drug assets currently in development for applications primarily in neurology. Our efforts are currently focused on addressing the high unmet medical needs in central nervous system disorders including Amyotrophic Lateral Sclerosis (“ALS”), Multiple Sclerosis (“MS”), and Parkinson’s Disease (“PD”). Our patented electro-crystal-chemistry manufacturing platform further enables us to develop very low concentration dietary supplements to advance the health and well-being of broad populations. These dietary supplements can vary greatly and include nanocrystals of varying composition, shapes and sizes as well as ionic solutions with diverse metallic constituents. Dietary supplements are marketed and distributed through our wholly owned subsidiary, dOrbital, Inc., or through an exclusive license with 4Life Research LLC (“4Life”), a related party (see Note 17).

Going Concern

We incurred a loss from operations of $48.4 million and $50.0 million for the years ended December 31, 2022 and 2021, respectively. Our accumulated deficit was $193.2 million and $163.3 million as of December 31, 2022 and 2021. Our cash, cash equivalents, and marketable securities totaled $23.3 million and $50.3 million as of December 31, 2022 and 2021, respectively, and net cash used in operating activities was $39.0 million and $34.6 million for the years ended December 31, 2022 and 2021, respectively.

We have incurred significant losses and negative cash flows from operations since our inception. We have not generated significant revenues since our inception, and we do not anticipate generating significant revenues unless we successfully complete development and obtain regulatory approval for commercialization of a drug candidate. We expect to incur additional losses in the future, particularly as we advance the development of our clinical-stage drug candidates, continue research and development of our preclinical drug candidates, and initiate additional clinical trials of, and seek regulatory approval for, these and other future drug candidates. We expect that within the next twelve months, we may not have sufficient cash and other resources on hand to sustain our current operations or meet our obligations as they become due, and we may need to obtain additional financing. Additionally, pursuant to our term loan with Avenue Venture Opportunities Fund, L.P. (“Avenue”), we are required to maintain unrestricted cash and cash equivalents of at least $5.0 million to avoid acceleration of the full balance of the loan (see Note 9). These conditions raise substantial doubt about the Company’s ability to continue as a going concern.

To mitigate our funding needs, we plan to raise additional funding, including exploring equity financing and offerings, debt financing, licensing or collaboration arrangements with third parties, as well as utilizing our existing at-the-market facility. These plans are subject to market conditions and reliance on third parties, and there is no assurance that effective implementation of our plans will result in the necessary funding to continue current operations. Subsequent to December 31, 2022, we have raised $3.9 million through our at-the-market facility and we entered into an equity line of credit with Lincoln Park Capital Fund, LLC (“Lincoln Park”) for up to $25.0 million (see Note 19). We have implemented cost-saving initiatives, including delaying and reducing research and development programs and commercialization efforts, reduction in executive compensation, a hiring freeze, and elimination of certain staff positions. We have concluded that our plans do not alleviate the substantial doubt about our ability to continue as a going concern beyond one year from the date the consolidated financial statements are issued.

The accompanying consolidated financial statements have been prepared assuming we will continue as a going concern, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. As a result, the accompanying consolidated financial statements do not include any adjustments relating to the recoverability and classification of assets and their carrying amounts, or the amounts and classification of liabilities that may result should we be unable to continue as a going concern.

Impact of the COVID-19 Pandemic

We are subject to risks and uncertainties as a result of the COVID-19 pandemic. The extent of the impact of the COVID-19 pandemic, including the resurgence of cases relating to the spread of new variants, on our business and operations is highly uncertain and difficult to predict, as the responses that we, other businesses, and governments are taking continue to evolve. Government measures taken in response to the COVID-19 pandemic have had a significant impact, both direct and indirect, on businesses, commerce, and economies worldwide, as worker shortages have occurred, supply chains have been disrupted, and facilities and production have been suspended. The COVID-19 pandemic may affect our ability to initiate and complete preclinical studies and clinical trials, delay the initiation of future clinical trials, disrupt regulatory activities, or have other adverse effects on our business and operations. In particular, we and our third-party contract research organizations (“CROs”) have faced disruptions that affected our ability to initiate and complete preclinical studies, caused manufacturing disruptions, and created delays at clinical trial site initiation and clinical trial enrollment, which ultimately led to the early conclusion of a clinical trial.

We are monitoring the potential impact of the COVID-19 pandemic on our business, financial condition, results of operations, and cash flows. While the COVID-19 pandemic has led to various research restrictions and led to pauses and early conclusion of one of our clinical trials, these impacts have been temporary and to date we have not experienced material business disruptions or incurred impairment losses in the carrying values of our assets as a result of the COVID-19 pandemic. We are not aware of any specific related event or circumstance that would require us to revise the estimates reflected in our consolidated financial statements. The extent to which the COVID-19 pandemic will directly or indirectly impact our business, financial condition, results of operations, and cash flows, including planned future clinical trials and research and development costs, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19, the actions taken to contain or treat it, and the duration and intensity of the related effects.

Note 2 - Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2022

Significant Accounting Policies [Text Block]

Note 2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying consolidated financial statements include the accounts of Clene Inc. and our wholly-owned subsidiaries, Clene Nanomedicine, Inc. (“Clene Nanomedicine”), a subsidiary incorporated in Delaware, Clene Australia Pty Ltd (“Clene Australia”), a subsidiary incorporated in Australia, Clene Netherlands B.V. (“Clene Netherlands”), a subsidiary incorporated in the Netherlands, and dOrbital, Inc., a subsidiary incorporated in Delaware, after elimination of all intercompany accounts and transactions. We have prepared the accompanying consolidated financial statements in accordance with United States (“U.S.”) Generally Accepted Accounting Principles (“GAAP”) In the opinion of management, the consolidated financial statements reflect all adjustments, which are normal and recurring in nature, necessary for fair financial statement presentation.

Use of Estimates

The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, and disclosure of contingent assets and liabilities, and the reported amounts of expenses. We base our estimates on historical experience and various other assumptions that we believe to be reasonable. Actual results may differ from those estimates or assumptions. Estimates are periodically reviewed in light of changes in circumstances, facts, and experience, and any changes in estimates will be recorded in future periods as they develop.

Risks and Uncertainties

The product candidates we develop require approvals from regulatory agencies prior to commercial sales. There can be no assurance that our current and future product candidates will receive the necessary approvals or be commercially successful. If we are denied approval or approval is delayed, it will have a material adverse impact on our business and our consolidated financial statements.

We are subject to certain risks and uncertainties and believe that changes in any of the following areas could have a material adverse effect on future financial condition, results of operations, or cash flows: ability to obtain additional financing; regulatory approval and market acceptance of, and reimbursement for, product candidates; performance of third-party CROs and manufacturers upon which we rely; protection of our intellectual property; litigation or claims against us based on intellectual property, patent, product, regulatory, or other factors; and our ability to attract and retain employees necessary to support our growth.

Concentrations of Credit Risk

Financial instruments which potentially subject us to significant concentrations of credit risk consist primarily of cash. Our cash is mainly held in financial institutions. Amounts on deposit may at times exceed federally insured limits. We have not experienced any losses on our deposits of cash and do not believe that we are subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

Cash and Cash Equivalents

We consider all short-term investments with original maturities of 90 days or less when purchased to be cash equivalents.

Restricted Cash

We classify cash as restricted when it is unavailable for withdrawal or use in our general operating activities. Restricted cash and investments are classified as current and noncurrent on the consolidated balance sheets based on the nature of the restriction. Our restricted cash balance includes contractually restricted deposits related to our corporate credit card.

Marketable Securities

Marketable securities are investments with original maturities of more than 90 days when purchased. We do not invest in securities with original maturities of more than one year. Marketable debt securities are considered available-for-sale, and are recorded at fair value, with unrealized gains and losses included as a component of accumulated other comprehensive income (loss) until realized. Realized gains and losses are included in other income (expense), net, on the basis of specific identification. The cost of marketable securities is adjusted for amortization of premiums or accretion of discounts to maturity, and such amortization or accretion is included in other income (expense), net.

Accounts Receivable

Accounts receivable are stated at invoice value less estimated allowances for sales returns and doubtful accounts. We estimate the allowance for sales returns based on historical percentage of returns over a 12-month trailing average of sales. We continually monitor customer payments and maintain a reserve for expected losses resulting from our customers’ inability to make required payments. We consider factors when estimating the allowance for doubtful accounts such as historical experience, age of the accounts receivable balances, geographic related risks, and economic conditions that may affect a customer’s ability to pay. In cases where there are circumstances that may impair a specific customer’s ability to meet its financial obligations, a specific allowance is recorded against amounts due, thereby reducing the net recognized receivable to the amount reasonably believed to be collectible. Accounts receivable are written off when deemed uncollectible. Recoveries of accounts receivable previously written off are recorded when received. Historically, there have been no sales returns, no written-off accounts receivable, and no allowance for doubtful accounts reducing the balance of the accounts receivable.

Inventory

Inventory is stated at historic cost on a first-in first-out basis. Our inventory consisted of $29,000 in raw materials and $14,000 in finished goods as of December 31, 2022, and $26,000 in raw material and $15,000 in finished goods as of December 31, 2021. Inventory primarily relates to our Supplements segment.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation. Property and equipment consist of laboratory and office equipment, computer software, and leasehold improvements. Depreciation is calculated using the straight-line method over the estimated economic useful lives of the assets, which are 3-5 years for laboratory equipment, 3-7 years for furniture and fixtures, and 2-5 years for computer software. Leasehold improvements are amortized over the lesser of the estimated lease term or the estimated useful life of the assets. Costs for capital assets not yet placed into service are capitalized as construction in progress and depreciated or amortized in accordance with the above useful lives once placed into service. Upon retirement or sale, the related cost and accumulated depreciation and amortization are removed from the accounts and any resulting gain or loss is included in the consolidated statements of operations and comprehensive loss. Maintenance and repairs that do not improve or extend the lives of the respective assets are expensed to operations as incurred.

We capitalize costs to obtain or develop computer software for internal use, including development costs incurred during the software development stage and costs to obtain software for access and conversion of historical data. We also capitalize costs to modify, upgrade, or enhance existing internal-use software that result in additional functionality. We expense costs incurred during the preliminary project stage, training costs, data conversion costs, and maintenance costs.

Impairment of Long-Lived Assets

Long-lived assets are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors we consider in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends, and significant changes or planned changes in the use of assets. If an impairment review is performed to evaluate an asset group for recoverability, we compare the forecasted undiscounted cash flows expected to result from the use and eventual disposition of the asset group to its carrying value. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use and eventual disposition of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows using market participant assumptions. We did not record any impairment losses on long-lived assets during the years ended December 31, 2022 and 2021.

Debt

When debt is issued and a derivative is required to be separated (e.g., bifurcated conversion option) or another separate freestanding financial instrument (e.g., warrant) is issued, costs and fees incurred are allocated to the instruments issued (or bifurcated) in proportion to the allocation of proceeds. When some portions of the costs and fees relate to a bifurcated derivative or freestanding financial instrument that is being subsequently measured at fair value, those allocated costs are expensed immediately. Debt discounts, debt premiums, and debt issuance costs related to debt are recorded as deductions that net against the principal value of the debt and are amortized to interest expense over the contractual term of the debt using the effective interest method.

Convertible Debt

In accordance with ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity, when we issue notes with conversion features, we evaluate if the conversion feature is freestanding or embedded. If the conversion feature is embedded, we do not separate the conversion feature from the host contract for convertible notes that are not required to be accounted for as derivatives, or that do not result in substantial premiums accounted for as paid-in-capital. Consequently, we account for a convertible note as a single liability measured at its amortized cost, and we account for a convertible preferred stock as a single equity instrument measured at its historical cost, as long as no other features require separation and recognition as derivatives.

If the conversion feature is freestanding, or is embedded and meets the requirements to be separated, we account for the conversion feature as a derivative under ASC 815, Derivatives and Hedging (“ASC 815”). We record the derivative instrument at fair value at inception, and subsequently re-measure to fair value at each reporting period and immediately prior to the extinguishment of the derivative instrument, with any changes recorded in the consolidated statements of operations and comprehensive loss.

Debt With Warrants

In accordance with ASC 470-20, Debt with Conversion and Other Options, when we issue debt with warrants, we treat the warrants as a debt discount, recorded as a contra-liability against the debt, and amortize the balance over the life of the underlying debt as interest expense in the consolidated statements of operations and comprehensive loss. The offset to the contra-liability is recorded as additional paid-in capital in the consolidated balance sheets if the warrants are not treated as a derivative or liability under ASC 480, Distinguishing Liabilities from Equity (“ASC 480”). Otherwise, the offset to the contra-liability is recorded as a warrant liability in the consolidated balance sheets and is subject to re-measurement to fair value at each balance sheet date, with any changes in fair value recognized in the consolidated statements of operations and comprehensive loss. If the debt is retired early, the associated debt discount is then recognized immediately as interest expense in the consolidated statements of operations and comprehensive loss.

Deferred Offering Costs

We capitalize certain legal, professional accounting, and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of the equity financing, these costs are recorded in stockholders’ equity as a reduction of proceeds generated as a result of the offering. Should any in-process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the consolidated statements of operations and comprehensive loss. As of December 31, 2022 and 2021, we did not have any deferred offering costs.

Leases

At inception of a contract, we determine if a contract meets the definition of a lease. We determine if the contract conveys the right to control the use of an identified asset for a period of time. We assess throughout the period of use whether we have both of the following: (i) the right to obtain substantially all of the economic benefits from use of the identified asset, and (ii) the right to direct the use of the identified asset. This determination is reassessed if the terms of the contract are changed. Leases are classified as operating or finance leases based on the terms of the lease agreement and certain characteristics of the identified asset. Right-of-use assets and lease liabilities are recognized at the lease commencement date based on the present value of the future lease payments less any lease incentives received. At the lease commencement date, the discount rate implicit in the lease is used to discount the lease liability if readily determinable. If not readily determinable or leases do not contain an implicit rate, our incremental borrowing rate is used as the discount rate.

Our policy is to not record leases with an original term of twelve months or less within the consolidated balance sheets. We recognize lease expense for these short-term leases on a straight-line basis over the lease term in the consolidated statements of operations and comprehensive loss.

Certain lease agreements may require us to pay additional amounts for taxes, insurance, maintenance, and other expenses, which are generally referred to as non-lease components. Such variable non-lease components are treated as variable lease payments and recognized in the period in which the obligation for these payments is incurred. Variable lease components and variable non-lease components are not measured as part of the right-of-use asset and liability. Only when lease components and their associated non-lease components are fixed are they accounted for as a single lease component and are recognized as part of a right-of-use asset and liability. Total contract consideration is allocated to the fixed lease and non-lease component. This policy election applies consistently to all asset classes under lease agreements.

Leases may contain clauses for renewal at our option. Payments to be made in option periods are recognized as part of the right-of-use lease assets and lease liabilities when it is reasonably certain that the option to extend the lease will be exercised, or is not at our option. We determine whether the reasonably certain threshold is met by considering contract-, asset-, market-, and entity-based factors. In the consolidated statements of operations and comprehensive loss, operating lease expense, which is recognized on a straight-line basis over the lease term, and the amortization of finance lease right-of-use assets, which are included in property and equipment and depreciated, are included in research and development or general and administrative expenses consistent with the leased assets’ primary use. Accretion on the liabilities for finance leases is included in interest expense.

Contingent Earn-Out Liabilities

In connection with the Reverse Recapitalization, certain stockholders are entitled to receive additional shares of Clene Inc. common stock, par value $0.0001 (“Common Stock”) (the “Contingent Earn-outs”) upon us achieving certain milestones (see Note 3). In accordance with Accounting Standards Codification (“ASC”) 815, Derivatives and Hedging (“ASC 815”), the Contingent Earn-outs are not indexed to our own stock and therefore are accounted for as a liability at the Reverse Recapitalization date and subsequently remeasured at each reporting date with changes in fair value recorded as a component of other income (expense), net.

Common Stock Warrants

We account for common stock warrants as either equity-classified instruments or liability-classified instruments based on an assessment of the warrant terms and applicable authoritative guidance. The assessment considers whether the warrants are freestanding financial instruments pursuant to ASC 480, meet the definition of a liability pursuant to ASC 480, and whether the warrants meet all of the requirements for equity classification under ASC 815, including whether the warrants are indexed to our Common Stock, among other conditions for equity classification. This assessment, which requires the use of professional judgment, is conducted at the time of warrant issuance and, for liability-classified warrants, at each reporting period end date while the warrants are outstanding.

Revenue Recognition

Under ASC 606, Revenue from Contracts with Customers (“ASC 606”), an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. We only apply the five-step model to contracts when it is probable that we will collect the consideration to which we are entitled in exchange for the goods or services we transfer to the customer.

Once a contract is determined to be within the scope of ASC 606 at contract inception, we review the contract to determine which performance obligations we must deliver, and which performance obligations are distinct. We recognize as revenue the amount of the transaction price that is allocated to each performance obligation when that performance obligation is satisfied or as it is satisfied. We typically satisfy our performance obligations via delivery of dietary supplements to the customer. Payments are due upon receipt for commercial transactions, or a prepayment is collected for online retail sales. Our revenue during the years ended December 31, 2022 and 2021 was comprised of sales of dietary supplements and royalties from sales of dietary supplements.

Grant Funding

We may submit applications to receive grant funding from governmental and non-governmental entities. We account for grants by analogizing to the grant accounting model under IAS 20, Accounting for Government Grants and Disclosure of Government Assistance (“IAS 20”).

We recognize grant funding without conditions or continuing performance obligations, including certain research and development tax credits, as other income in the consolidated statements of operations and comprehensive loss. We accrue certain research and development tax credits receivable in other current assets (see Note 5) in the consolidated balance sheets in an amount equal to the qualifying expenses incurred in each period multiplied by the applicable reimbursement percentage and we recognize other income in the consolidated statements of operations and comprehensive loss. After submission of our tax returns, we receive a cash refund of certain research and development tax credits and relieve the receivable.

We recognize grant funding with conditions or continuing performance obligations as a reduction in research and development expenses in the consolidated statements of operations and comprehensive loss in the period during which the related qualifying expenses are incurred and as the conditions or performance obligations are fulfilled. Any amount received in advance of fulfilling such conditions or performance obligations is recorded in accrued liabilities in the consolidated balance sheets if the conditions or performance obligations are expected to be met within the next twelve months. We recorded grants as a reduction of research and development expenses of $0 and $0.2 million for the years ended December 31, 2022 and 2021, respectively.

Fair Value of Financial Instruments

Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy:

Level 1—Inputs based upon quoted market prices for identical assets or liabilities in active markets at the measurement date.

Level 2—Observable inputs other than quoted market prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data.

Level 3—Inputs that are management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. The inputs are unobservable in the market and significant to the instrument’s valuation.

We review the fair value hierarchy classification of our applicable assets and liabilities on a quarterly basis. Changes in the observability of valuation inputs may result in a reclassification for certain financial assets or liabilities. Reclassifications impacting all levels of the fair value hierarchy are reported as transfers in or out of the Level 1, 2, or 3 categories as of the beginning of the period during which the reclassifications occur.

Foreign Currency Translation and Transactions

Our functional currency is the U.S. dollar. Clene Australia determined its functional currency to be the Australian dollar and Clene Netherlands determined its functional currency to be the Euro. We use the U.S. dollar as our reporting currency for the consolidated financial statements. The results of our non-U.S. dollar based functional currency operations are translated to U.S. dollars at the average exchange rates during the period. Our assets and liabilities are translated using the current exchange rate as of the balance sheet date and stockholders’ equity is translated using historical rates.

Adjustments resulting from the translation of the consolidated financial statements of our foreign functional currency subsidiaries into U.S. dollars are excluded from the determination of net loss and are accumulated in a separate component of stockholders’ equity.

We also incur foreign exchange transaction gains and losses for purchases denominated in foreign currencies. Foreign exchange transaction gains and losses are included in other income (expense), net, as incurred.

Comprehensive Loss

Comprehensive loss includes net loss as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. The only elements of other comprehensive loss in any periods presented were translation of foreign currency denominated balances of Clene Australia and Clene Netherlands to U.S. dollars for consolidation and unrealized loss on available-for-sale securities.

Net Loss Per Share Attributable to Common Stockholders

Basic net loss per share attributable to common stockholders is calculated using our weighted-average outstanding common shares. Diluted net loss per share attributable to common stockholders is calculated using our weighted-average outstanding common shares including the dilutive effect of securities as determined under the treasury stock method, except for the dilutive effect of convertible notes payable, which is calculated under the if-converted method, even if the embedded conversion option is out-of-the-money. In periods in which we report a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.

Segment Information

We have determined that our chief executive officer is the chief operating decision maker (“CODM”). Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the CODM in making decisions regarding resource allocation and assessing performance. We view our operations and manage our business in two operating segments, which are our reportable segments: (1) the development and commercialization of novel clean-surfaced nanotechnology therapeutics (“Drugs”), and (2) the development and commercialization of dietary supplements (“Supplements”).

Income Taxes

We account for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in our tax returns. Deferred tax assets and liabilities are determined based on the differences between the financial statement basis and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. We assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies.

We account for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than-not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, which are considered appropriate as well as the related net interest and penalties.

Stock-Based Compensation

We account for stock-based compensation arrangements using a fair value-based method for costs related to all share-based payments including stock options and stock awards. Stock-based compensation expense is recorded in research and development and general and administrative expenses based on the classification of the work performed by the grantees.

The fair value is recognized over the period during which a grantee is required to provide services in exchange for the option award and service-based stock awards, known as the requisite service period (usually the vesting period), on a straight-line basis. For stock awards with market conditions, the fair value is recognized over the period based on the expected milestone achievement dates as the derived service period (usually the vesting period), on a straight-line basis. For stock awards with performance conditions, the grant-date fair value of these awards is the market price on the applicable grant date, and compensation expense will be recognized when the conditions become probable of being satisfied. We recognize a cumulative true-up adjustment once the conditions become probable of being satisfied as the related service period had been completed in a prior period.

Stock-based compensation expense is recognized at fair value. We elect to account for forfeitures as they occur, rather than estimating expected forfeitures.

We determine the fair value of each share of Common Stock underlying stock-based awards using a Black-Scholes option pricing model based on the closing price of our Common Stock as reported by the Nasdaq Capital Market (“Nasdaq”) on the date of grant. The fair value of stock awards with market conditions are determined using a Monte Carlo valuation model.

Research and Development

Research and development costs are charged to expense as incurred. We account for nonrefundable advance payments for goods and services that will be used in future research and development activities as expenses when the goods have been received or when the service has been performed. Research and development expenses consist of costs incurred for the discovery and development of our product candidates. Research and development costs include, but are not limited to, payroll and personnel expenses including stock-based compensation, clinical trial supplies, fees for clinical trial services, consulting costs, and allocated overhead, including rent, equipment, and utilities.

Clinical Trial Accrual

Our clinical trial accrual process accounts for expenses resulting from obligations under contracts with CROs, consultants, and under clinical site agreements in connection with conducting clinical trials. Clinical trial costs are charged to research and development expense as incurred. The financial terms of these contracts are subject to negotiations, which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided to us under such contracts. We reflect the appropriate clinical trial expense in the consolidated financial statements by matching the appropriate expenses with the period in which services and efforts are expended. In the event advance payments are made to a CRO, the payments will be recorded as a prepaid asset which will be amortized to research and development expense over the period the contracted services are performed. In addition to pass-through costs, we generally incur costs in clinical trials in four distinct groups as follows:

CRO Start-Up—These costs include the initial set-up of the clinical trial and usually occur within a few months after the contract has been executed and includes costs which are expensed ratably over the start-up period when such period is identifiable and expensed as incurred when no such period exists. Start-up phase activities include study initiation, site recruitment, regulatory applications, investigator meetings, screening, preparation, pre-study visits, and training.

CRO Site and Study Management—These costs include medical and safety monitoring, patient administration and data management. These costs are usually calculated on a per-patient basis and expensed ratably over the treatment period beginning on the date that the patient enrolls.

CRO Close-Down and Reporting—These costs include analyzing the data obtained and reporting results, which occurs after patients have ceased treatment and the database of information collected is locked. These costs are expensed as incurred over the course of any close-down and reporting period.

Third-Party Contracts—These costs include fees charged by third parties for various support services which are not provided by CROs and include such items as laboratory fees, data quality review costs, and fees incurred for investigational product monitoring and inventory control. These items are expensed ratably over any identifiable service period with the engaged third-party vendors.

The CRO contracts generally include pass-through fees including, but not limited to, regulatory expenses, investigator fees, travel costs, and other miscellaneous costs, including shipping and printing fees. We determine accrual estimates through reports from and discussion with applicable personnel and outside service providers as to the progress or state of completion of trials or the services completed. We estimate accrued expenses as of each reporting date in the consolidated financial statements based on the facts and circumstances known to us at that time.

Recently Adopted Accounting Pronouncements

In May 2021, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2021-04, Earnings Per Share (Topic 260), Debt—Modifications and Extinguishments (Subtopic 470-50), Compensation—Stock Compensation (Topic 718), and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40). The amendments in this update relate to the recognition and measurement of earnings per share for certain modifications or exchanges of equity-classified written call options or warrants. The guidance was effective for our fiscal year and interim periods within our fiscal year beginning after December 15, 2021. The adoption of this guidance did not have an impact on our consolidated financial statements.

In November 2021, the FASB issued ASU 2021-10, Government Assistance (Topic 832): Disclosures by Business Entities about Government Assistance. The amendments in this update add disclosure requirements for transactions with a government that are accounted for by applying a grant or contribution accounting model by analogy, including disclosure about the nature of the transactions, accounting policy, affected line items in the balance sheet and income statement, amounts applicable to each financial statement line item, and significant terms and conditions of the transactions including commitments and contingencies. The guidance was effective for our financial statements issued for annual periods beginning after December 15, 2021 and impacted our disclosures under Note 2—“Grant Funding” related to government grants and certain research and development tax credits, which are accounted for by analogizing to the grant accounting model under IAS 20.

Recent Accounting Pronouncements Not Yet Adopted

In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The amendments in this update, among other things, require the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Financial institutions and other organizations will now use forward-looking information to better inform their credit loss estimates. As a smaller reporting company, the guidance is effective for our fiscal years beginning after December 15, 2022. We are currently evaluating the expected impact, if any, of the new guidance as a result of this extended deadline of implementation for smaller reporting companies.

Note 3 - Reverse Recapitalization with Tottenham and Clene Nanomedicine

12 Months Ended

Dec. 31, 2022

Business Combination Disclosure [Text Block]

Note 3. Reverse Recapitalization with Tottenham and Clene Nanomedicine

On December 30, 2020 (the “Closing Date”), Chelsea Worldwide Inc., our predecessor, consummated the Reverse Recapitalization by and among Clene Nanomedicine, Tottenham Acquisition I Limited (“Tottenham”), Chelsea Worldwide Inc. (“PubCo”), a Delaware corporation and wholly-owned subsidiary of Tottenham, Creative Worldwide Inc. (“Merger Sub”), a Delaware corporation and wholly-owned subsidiary of PubCo, and Fortis Advisors LLC, a Delaware limited liability company as the representative of our stockholders. The Reverse Recapitalization was effected in two steps: (i) Tottenham was reincorporated to the state of Delaware by merging with and into PubCo (the “Reincorporation Merger”); and (ii) promptly following the Reincorporation Merger, Merger Sub was merged with and into Clene Nanomedicine, resulting in Clene Nanomedicine becoming a wholly-owned subsidiary of PubCo (the “Acquisition Merger”). On the Closing Date, PubCo changed its name from Chelsea Worldwide Inc. to Clene Inc. and listed its shares of Common Stock, par value $0.0001 per share on Nasdaq under the symbol “CLNN.”

We received gross proceeds of $9.4 million from the Reverse Recapitalization and incurred offering costs of $5.9 million, which excludes the fair value of Common Stock issued as payment of certain offering costs, resulting in net proceeds of $3.5 million. We paid LifeSci Capital LLC, an advisor to Clene Nanomedicine, 644,164 shares of Common Stock as consideration for its services.

The transaction was accounted for as a “reverse recapitalization” in accordance with GAAP. Under this method of accounting, Tottenham was treated as the “acquired” company for financial reporting purposes. This determination was primarily based on the fact that subsequent to the Reverse Recapitalization, Clene Nanomedicine’s stockholders have a majority of the voting power of the Company, Clene Nanomedicine comprises all of the ongoing operations of the Company, Clene Nanomedicine comprises a majority of the governing body of the Company, and Clene Nanomedicine’s senior management comprises all of the senior management of the Company. Accordingly, for accounting purposes, this transaction was treated as the equivalent of Clene Nanomedicine issuing shares for the net assets of Tottenham, accompanied by a recapitalization.

Earn-Out Shares

Certain of Clene Nanomedicine’s stockholders are entitled to receive earn-out shares (the “Clene Nanomedicine Contingent Earn-out”) as follows : (i) 3,333,333 shares of Common Stock if (a) the volume-weighted average price (“VWAP”) of the shares of our Common Stock equals or exceeds $15.00 (the “Milestone 1 Price”) in any twenty trading days within a thirty trading day period within three years of the closing of the Reverse Recapitalization or (b) the change of control price equals or exceeds the Milestone 1 Price if a change of control transaction occurs within three years of the closing of the Reverse Recapitalization (the requirements in (a) and (b) collectively, “Milestone 1”); (ii) 2,500,000 shares of Common Stock if (a) the VWAP of our Common Stock equals or exceeds $20.00 (the “Milestone 2 Price”) in any twenty trading days within a thirty trading day period within five years of the closing of the Reverse Recapitalization or (b) the change of control price equals or exceeds the Milestone 2 Price if a change of control transaction occurs within five years of the closing of the Reverse Recapitalization (the requirements in (a) and (b) collectively, “Milestone 2”); and (iii) 2,500,000 shares of Common Stock if Clene Nanomedicine completed a randomized placebo-controlled clinical trial for treatment of COVID-19 which results in a statistically significant finding of clinical efficacy within twelve months of the closing of the Reverse Recapitalization (“Milestone 3”), which was not achieved. If Milestone 1 is not achieved but Milestone 2 is achieved, the Clene Nanomedicine stockholders will receive an issuance equal to the shares to be issued upon satisfaction of Milestone 1. As of the Closing Date, the Clene Nanomedicine Contingent Earn-out shares increased by 12,852 to 8,346,185 shares of Common Stock due to exercises of stock options during November 2020.

Tottenham’s former officers and directors, sponsor, and public stockholders (the “Initial Stockholders”) may be entitled to receive earn-out shares as follows (the “Initial Stockholders Contingent Earn-out”): (i) 375,000 shares of Common Stock upon satisfaction of the requirements of Milestone 1; and (ii) 375,000 shares of Common Stock upon satisfaction of the requirements of Milestone 2. If Milestone 1 is not achieved but Milestone 2 is achieved, the Initial Stockholders will receive an issuance equal to the shares to be issued upon satisfaction of Milestone 1.

The Contingent Earn-outs shares have been classified as liabilities in the consolidated balance sheets and are remeasured to fair value at each reporting date. We did not achieve Milestone 3 and 2,503,851 Milestone 3 Contingent Earn-out shares were cancelled as of December 31, 2021.

Note 4 - Marketable Securities

12 Months Ended

Dec. 31, 2022

Cash, Cash Equivalents, and Marketable Securities [Text Block]

Note 4. Marketable Securities

Available-for-Sale Securities

Available-for-sale securities are recorded at fair value, with unrealized gains and losses included as a component of accumulated other comprehensive income (loss) until realized. Available-for-sale securities as of December 31, 2022 were as follows:

	*December 31, 2022*
(in thousands)	*Amortized Cost*		*Gross Unrealized Gains*		*Gross Unrealized Losses*			*Fair Value*
Commercial paper	$	3,496	$	—	$	(14	)	$	3,482
Corporate debt securities		1,501		—		—			1,501
Total	$	4,997	$	—	$	(14	)	$	4,983

As of December 31, 2021, there were no outstanding available-for-sale securities. Proceeds from the sale and maturity of available-for-sale securities were as follows:

	Year Ended December 31,
(in thousands)	2022		2021
Proceeds from maturities and calls of marketable securities	$	12,015	$	—
Proceeds from sales of marketable securities	$	7,614		—
Total	$	19,629	$	—

Realized gains and losses included in earnings from the sale of available-for-sale securities were insignificant. All available-for-sale securities had a contractual maturity within one year. As of December 31, 2022, we did not have any allowance for credit losses or impairments of available-for-sale securities.

Note 5 - Prepaid Expenses and Other Current Assets

12 Months Ended

Dec. 31, 2022

Prepaid Expenses and Other Current Assets [Text Block]

Note 5. Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets as of December 31, 2022 and 2021 were as follows:

(in thousands)	*2022*		*2021*
Research and development tax credits receivable	$	2,777	$	1,564
Metals to be used in research and development		2,290		2,237
Other		581		404
Total prepaid expenses and other current assets	$	5,648	$	4,205

Note 6 - Property and Equipment, Net

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment Disclosure [Text Block]

Note 6. Property and Equipment, Net

Property and equipment, net, as of December 31, 2022 and 2021 were as follows:

(in thousands)	*2022*			*2021*
Lab equipment	$	3,934		$	3,327
Office equipment		177			147
Computer software		459			—
Leasehold improvements		5,677			3,943
Construction in progress		5,664			2,052
		15,911			9,469
Less accumulated depreciation		(5,273	)		(4,297	)
Total property and equipment, net	$	10,638		$	5,172

Depreciation expense recorded in research and development expense and general and administrative expense for the years ended December 31, 2022 and 2021 was as follows:

	Year Ended December 31,
(in thousands)	2022		2021
General and administrative	$	229	$	115
Research and development		790		840
Total depreciation expense	$	1,019	$	955

Note 7 - Accrued Liabilities

12 Months Ended

Dec. 31, 2022

Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]

Note 7. Accrued Liabilities

Accrued liabilities as of December 31, 2022 and 2021 were as follows:

(in thousands)	*2022*		*2021*
Accrued compensation and benefits	$	2,007	$	2,049
Accrued CRO and clinical fees		1,297		718
Deferred grant funds		520		520
Other		39		323
Total accrued liabilities	$	3,863	$	3,610

Note 8 - Leases

12 Months Ended

Dec. 31, 2022

Lessee, Operating and Finance Leases [Text Block]

Note 8. Leases

We lease laboratory and office space and certain laboratory equipment under non-cancellable operating and finance leases. The carrying value of our right-of-use lease assets is substantially concentrated in our real estate leases, while the volume of lease agreements is primarily concentrated in equipment leases.

Operating Leases

In September 2021, we commenced an operating lease for laboratory space and recorded a right-of-use asset of $2.4 million and lease liability of $2.4 million, net of a lease incentive of $1.0 million which represents an allowance from the lessor for facility alterations. As the lease incentive is payable based on events within our control and are deemed reasonably certain to occur, we recorded the lease incentive as a reduction of the right-of-use asset and lease liability at the lease commencement. As of December 31, 2022 and 2021, we had incurred $1.0 million and $0.5 million, respectively, of cumulative costs related to the lease incentive which we recorded as construction in progress, with a corresponding increase to the lease liability, and the construction in progress will be capitalized as leasehold improvements when the facility is placed into service. The lease has an initial ten-year term and provides us the right and option to extend or renew for two periods of five years each. In accordance with ASC 842, Leases, the payments to be made in option periods have not been recognized as part of the right-of-use asset or lease liability because we do not assess the exercise of the option to be reasonably certain.

In February 2022, we commenced an operating lease for existing laboratory space and recorded a right-of-use asset of $2.3 million and lease liability of $2.3 million and terminated the previous right-of-use asset of $0.6 million and lease liability of $1.0 million. We recorded a gain on termination of lease of $0.4 million in the consolidated statements of operations and comprehensive loss for the year ended December 31, 2022.

Our right-of-use assets pertain to operating leases. As of December 31, 2022 and 2021, our operating lease obligations had a weighted-average discount rate of 9.6% and 9.6%, respectively; and a weighted-average remaining term of 7.3 years and 8.1 years, respectively.

Finance Leases

Assets recorded under finance lease obligations and included with property and equipment as of December 31, 2022 and 2021 were as follows:

(in thousands)	*2022*			*2021*
Lab equipment	$	408		$	408
Work in process		228			228
Total		636			636
Less accumulated depreciation		(326	)		(244	)
Net	$	310		$	392

As of December 31, 2022 and 2021, our finance lease obligations had a weighted-average interest rate of 10.2% and 8.8%, respectively; and a weighted-average remaining term of 1.2 years and 1.9 years, respectively.

Maturity Analysis of Leases

The maturity analysis of our finance and operating leases as of December 31, 2022 were as follows:

(in thousands)	Finance Leases			Operating Leases
2023	$	96		$	1,051
2024		27			1,171
2025		—			1,202
2026		—			1,231
2027		—			1,129
Thereafter		—			2,786
Total undiscounted cash flows		123			8,570
Less amount representing interest/discounting		(15	)		(2,525	)
Present value of future lease payments		108			6,045
Less lease obligations, current portion		(74	)		(488	)
Lease obligations, long term portion	$	34		$	5,557

We expect that, in the normal course of business, the existing leases will be renewed or replaced by similar leases.

Components of Lease Cost

The components of finance and operating lease costs for the years ended December 31, 2022 and 2021 were as follows:

	*Year Ended December 31,*
(in thousands)	*2022*		*2021*
Finance lease costs:
Amortization	$	82	$	82
Interest on lease liabilities		16		27
Operating lease costs		948		429
Short-term lease costs		1		73
Variable lease costs		304		130
Total lease costs	$	1,351	$	741

Supplemental Cash Flow Information

	*Year Ended December 31,*
(in thousands)	*2022*			*2021*
Operating cash flows from operating leases	$	(1,253	)	$	(633	)
Operating cash flows from finance leases	$	(16	)	$	(27	)
Financing cash flows from finance leases	$	(135	)	$	(152	)

Note 9 - Notes Payable and Convertible Notes Payable

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Text Block]

Note 9. Notes Payable and Convertible Notes Payable

Our notes payable and convertible notes payable as of December 31, 2022 and 2021 was as follows:

(in thousands, except interest rates)	*Stated Interest Rate*			*2022*			*2021*
Notes payable
Advance Cecil, Inc. (commenced April 2019)		8.00	%	$	130		$	122
Maryland DHCD (commenced February 2019)		8.00	%		654			614
Maryland DHCD (commenced May 2022)		6.00	%		682			—
Avenue Venture Opportunities Fund, L.P. (commenced May 2021)		14.10	%		15,000			15,000
					16,466			15,736
Accrued and unpaid interest					22			—
Less unamortized discount and debt issuance costs					(587	)		(1,252	)
Less notes payable, current portion, net of unamortized discount					(6,418	)		—
Total notes payable, net of current portion				$	9,483		$	14,484

Convertible notes payable
Avenue Venture Opportunities Fund, L.P. (commenced May 2021)		14.10	%	$	5,000		$	5,000
Maryland DHCD (commenced December 2022)		6.00	%		5,000			—
					10,000			5,000
Accrued and unpaid interest					7			—
Less unamortized discount and debt issuance costs					(237	)		(402	)
Total convertible notes payable				$	9,770		$	4,598

Maryland DHCD Loans

In February 2019, we entered into a loan agreement (the “2019 MD Loan”) with the Department of Housing and Community Development (“DHCD”), a principal department of the State of Maryland. The agreement provides for a term loan of $0.5 million bearing simple interest at an annual rate of 8.00%. We are subject to affirmative and negative covenants until maturity, including providing information about the Company and our operations; limitations on our ability to retire, repurchase, or redeem our common or preferred stock, options, and warrants other than per the terms of the securities; and limitations on our ability to pay dividends of cash or property. There are no financial covenants associated with the 2019 MD Loan. As of December 31, 2022, we were not in violation of any covenants. The 2019 MD Loan established “Phantom Shares” at issuance based on 119,907 shares of Common Stock. Repayment of the full balance is due on February 22, 2034, with the repayment amount and carrying value equal to the greater of the balance of principal plus accrued interest or the value of the Phantom Shares. The value of the Phantom Shares is based on the closing price of our Common Stock on Nasdaq at the end of each reporting period. As of December 31, 2022 and 2021, the note was recorded at principal plus accrued interest in the consolidated balance sheets. We recognized interest expense of $40,000 and interest income of $0.5 million for the years ended December 31, 2022 and 2021, respectively.

In May 2022, we entered into a loan agreement (the “2022 MD Loan”) with DHCD, which provides for a term loan of up to $3.0 million bearing simple interest at an annual rate of 6.00% for the purchase of certain personal property (the “Assets”) related to the production of pharmaceutical drugs. As of December 31, 2022, we had drawn $0.7 million under the term loan, with the remainder available upon our submission of disbursement requests to purchase the Assets. The 2022 MD Loan matures on July 1, 2027. The first twelve payments, commencing on July 1, 2022, are deferred. Immediately thereafter, there shall be eighteen monthly installments of interest-only based on the actual amount advanced under the loan, each up to a maximum amount of $15,000; followed by thirty monthly installments of principal and interest, each in the amount of $33,306, which is due and payable even if the entire loan has not been advanced prior to the date such monthly payment is due and payable, with a balloon payment of all accrued and unpaid interest and principal due on the maturity date. We recorded $31,000 of debt issuance costs that are being amortized over the contractual term using the effective interest method. Pursuant to the 2022 MD Loan, DHCD was granted a continuing security interest in the Assets as collateral. Under a priority of liens agreement by and between DHCD and Avenue, an existing secured creditor of the Company, DHCD’s continuing security interest in the Assets shall be a first priority lien. We recognized interest expense of $23,000 for the year ended December 31, 2022.

In December 2022, we entered into a loan agreement (the “2022 DHCD Loan”) with DHCD for a term loan of $5.0 million bearing simple interest at an annual rate of 6.00%. The 2022 DHCD Loan matures on January 1, 2028. The first twelve payments, commencing on January 1, 2023, are deferred. Immediately thereafter, there shall be 48 monthly installments of interest only, with a balloon payment of all accrued and unpaid interest and the principal due on the maturity date. We recorded $0.1 million of debt issuance costs that are being amortized over the contractual term using the effective interest method. DHCD may, in its sole discretion, at any time after December 8, 2023, convert any portion of the outstanding balance of the 2022 DHCD Loan into Common Stock at the price of the greater of: (i) 97% of the 30-day trailing volume-weighted average sales price for the Common Stock, ending on and including the date on which the stock is purchased; or (ii) $4.00 per share (the “DHCD Conversion Feature”). DHCD may exercise the DHCD Conversion Feature in increments of $1.0 million. The DHCD Conversion Feature did not meet the requirements for separate accounting and is not accounted for as a derivative instrument. The number of shares of Common Stock contingently issuable upon conversion is 1,250,000 at the $4.00 per share minimum exercise price, assuming conversion of the entire principal balance. For the year ended December 31, 2022, we recognized (i) total interest expense of $7,200, (ii) coupon interest expense of $7,500, and (iii) amortization of debt discount and issuance costs of $300; and the effective interest rate was 5.91%.

Cecil County Loan

In April 2019, we entered into a loan agreement (the “2019 Cecil Loan”) with Advance Cecil Inc., a non-stock corporation formed under the laws of the state of Maryland. The agreement provides for a term loan of $0.1 million bearing simple interest at an annual rate of 8.00%. We are subject to affirmative covenants until maturity, including providing information about the Company and our operations. There are no financial covenants associated with the 2019 Cecil Loan. As of December 31, 2022, we were not in violation of any covenants. The 2019 Cecil Loan established “Phantom Shares” at issuance based on 23,981 shares of Common Stock. Repayment of the full balance is due on April 30, 2034, with the repayment amount and carrying value equal to the greater of the balance of principal plus accrued interest or the value of the Phantom Shares. The value of the Phantom Shares is based on the closing price of our Common Stock on Nasdaq at the end of each reporting period. As of December 31, 2022 and 2021, the note was recorded at principal plus accrued interest in the consolidated balance sheets. We recognized interest expense of $8,000 and interest income of $0.1 million for the years ended December 31, 2022 and 2021, respectively.

PPP Loan

In May 2020, we entered into a note payable in the amount of $0.6 million (the “PPP Loan”) under the Paycheck Protection Program of the CARES Act. The Paycheck Protection Program permits forgiveness of amounts loaned for payments of payroll and other qualifying expenses, subject to certain conditions. In January 2021, the full balance of the PPP Loan was forgiven and we recorded a gain on extinguishment of notes payable for the year ended December 31, 2021.

Avenue Loan

In May 2021, we entered into a loan agreement (the “2021 Avenue Loan”) with Avenue. The agreement provides for a 42-month term loan of up to $30.0 million. The first tranche is $20.0 million (“Tranche 1”), of which $15.0 million was funded at close and $5.0 million was funded in September 2021. We incurred issuance costs of $0.6 million of which $47,000 was expensed immediately. The remaining unfunded tranche of $10.0 million (“Tranche 2”) was not drawn and expired on December 31, 2022. The 2021 Avenue Loan bears interest at a variable rate equal to the sum of (i) the greater of (a) the prime rate or (b) 3.25%, plus (ii) 6.60%. As of December 31, 2022 and 2021, the interest rate was 14.10% and 9.85%, respectively. Payments are interest-only for the first 12 months and have been extended an additional 12 months (the “First Interest-only Period Extension”) based on our achievement of a statistically significant result in certain clinical trials (“Performance Milestone 1”). The loan principal will amortize equally from the end of the interest period to the expiration of the 42-month term on December 1, 2024. On the maturity date, an additional payment equal to 4.25% of the funded loans, or $0.9 million (the “Final Payment”), is due in addition to the remaining unpaid principal and accrued interest. The Final Payment was recorded as a debt premium and is being amortized over the contractual term using the effective interest method. The Final Payment is related to the loan host and did not meet the requirements for separate accounting and is not accounted for as a derivative instrument. We are subject to affirmative and negative covenants until maturity in the absence of prepayments, including providing information about the Company and our operations; limitation on our ability to retire, repurchase, or redeem our Common Stock, options, and warrants other than per the terms of the securities; and limitations on our ability to pay dividends of cash or property. Also pursuant to the 2021 Avenue Loan, we are required to maintain unrestricted cash and cash equivalents of at least $5.0 million, provided that upon our (i) achievement of Performance Milestone 1, and (ii) receiving of net proceeds of at least $30.0 million from the sale and issuance of our equity securities, we shall no longer be subject to financial covenants. As of December 31, 2022, we were not in violation of any covenants. Avenue also has the ability to make all obligations under the 2021 Avenue Loan immediately due and payable upon occurrence of certain events of default or material adverse effects, as outlined in the loan agreement. The 2021 Avenue Loan is collateralized by substantially all of our assets other than intellectual property, including our capital stock and the capital stock of our subsidiaries, in which Avenue is granted a continuing security interest.

Pursuant to the agreement, we granted Avenue a warrant to purchase 115,851 shares of Common Stock (the “Avenue Warrant”) at an exercise price of $8.63 per share. If Tranche 2 was funded, the Avenue Warrant would have been adjusted to include additional shares of Common Stock. We accounted for the Tranche 2 contingently-issuable warrant at inception of the 2021 Avenue Loan in accordance with ASC 815 and the fair value and issuable shares were remeasured at each reporting period. As Tranche 2 was not drawn as of December 31, 2022, the liability was extinguished and we recognized a gain in the consolidated statements of operations and comprehensive loss.

Avenue has the right, in its discretion, but not the obligation, at any time between May 21, 2022 through May 21, 2024, while the loan is outstanding, to convert up to $5.0 million of principal into Common Stock (the “Avenue Conversion Feature”) at a price per share equal to 120% of the Avenue Warrant exercise price. The Avenue Conversion Feature is subject to certain minimum price and volume conditions of our Common Stock on Nasdaq. The Avenue Conversion Feature did not meet the requirements for separate accounting and is not accounted for as a derivative instrument. The number of shares of Common Stock contingently issuable upon conversion is 482,703 shares. We classified $5.0 million of the 2021 Avenue Loan as convertible notes payable as of December 31, 2022 and 2021, with unamortized debt discount and issuance costs of $0.2 million and $0.4 million, respectively. For the convertible notes payable for the years ended December 31, 2022 and 2021, we recognized (i) total interest expense of $0.8 million and $0.4 million, respectively; (ii) coupon interest expense of $0.6 million and $0.3 million, respectively; and (iii) amortization of debt discount and issuance costs of $0.2 million and $0.1 million, respectively; and the effective interest rate was 19.69% and 15.46%, respectively.

The net proceeds from the issuance of the loan were initially allocated to the warrant at an amount equal to their fair value of $1.5 million and the remainder to the loan. The allocation of incurred financing costs of $0.5 million, which together with the fair value of the Avenue Warrant and the Final Payment, are recorded as a debt discount and debt premium, respectively, and are being amortized over the contractual term using the effective interest method. We recognized interest expense of $3.2 million and $1.5 million for the year ended December 31, 2022.

Future principal payments under the 2021 Avenue Loan, net of unamortized debt discounts, if Avenue does not exercise the Avenue Conversion Feature, and under the 2022 MD Loan and 2022 DHCD Loan, net of unamortized debt discounts, are as follows:

(in thousands)	2021 Avenue Loan			2022 MD Loan			2022 DHCD Loan
2023	$	6,667		$	—		$	—
2024		13,333			—			—
2025		—			369			—
2026		—			313			—
2027		—			—			—
Thereafter		—			—			5,000
Subtotal of future principal payments		20,000			682			5,000
Accrued and unpaid interest		—			22			7
Less unamortized discount and debt issuance costs		(747	)		(27	)		(50	)
Total	$	19,253		$	677		$	4,957

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Note 10 - Common Stock Warrants

12 Months Ended

Dec. 31, 2022

Common Stock Warrants Disclosure [Text Block]

Note 10. Common Stock Warrants

As of December 31, 2022 and 2021, outstanding warrants to purchase shares of Common Stock were as follows:

Date Exercisable

Number of
Shares
Issuable

Exercise Price

Exercisable for

Classification

Expiration

December 2020

2,407,500

⁽¹⁾

11.50

Common Stock

Equity

December 2025

December 2020

24,583

⁽²⁾

11.50

Common Stock

Equity

December 2025

December 2020

1,929,111

⁽³⁾

1.97

Common Stock

Equity

April 2023

May 2021

115,851

⁽⁴⁾

8.63

Common Stock

Equity

May 2026

Total

4,477,045

(1)

Consists of 2,407,500 shares of Common Stock underlying warrants to purchase one-half (1/2) of one share of Common Stock, issued in connection with Tottenham’s initial public offering. We may redeem the outstanding warrants, in whole and not in part, at $0.01 per warrant if the last sales price of our Common Stock equals or exceeds $16.50 per share for any twenty trading days within a thirty-trading day period. As of December 31, 2022 and 2021, no warrants had been exercised.

(2)

Consists of 24,583 shares of Common Stock underlying warrants to purchase one-half (1/2) of one share of Common Stock, issued to Chardan Capital Markets, LLC (“Chardan”) upon exercise of their unit purchase option, which was issued in connection with Tottenham’s initial public offering. As of December 31, 2022 and 2021, no warrants had been exercised.

(3)	Consists of 1,929,111 shares of Common Stock underlying warrants to purchase one share of Common Stock, issued by Clene Nanomedicine as Series A preferred stock and senior equity Warrants in August 2013. As of December 31, 2022 and 2021, none of the warrants had been exercised.

(4)	Consists of 115,851 shares of Common Stock underlying the Avenue Warrant. As of December 31, 2022 and 2021, the warrant had not been exercised.

Note 11 - Commitments and Contingencies

12 Months Ended

Dec. 31, 2022

Commitments and Contingencies Disclosure [Text Block]

Note 11. Commitments and Contingencies

Commitments

We enter into agreements in the normal course of business with CROs for clinical trials and with vendors for preclinical studies and other services and products for operating purposes, which are cancelable at any time by us, subject to payment of our remaining obligations under binding purchase orders and, in certain cases, nominal early termination fees. These commitments are not deemed significant.

As of December 31, 2022 and 2021, we had commitments under various agreements for capital expenditures totaling $1.6 million and $0.6 million, respectively, related to the construction of our manufacturing facilities.

Contingencies

From time to time, we may have certain contingent legal liabilities that arise in the ordinary course of business activities. We accrue a liability for such matters when it is probable that future expenditures will be made, and such expenditures can be reasonably estimated. We are not aware of any current material pending legal matters or claims.

In September 2019, we received grant funding of approximately $0.3 million from the National Multiple Sclerosis Society (“NMSS”) to fund biomarker research related our VISIONARY-MS Phase 2 clinical trial. Pursuant to a Sponsored Research Agreement with NMSS, if we make future commercial sales of CNM-Au8 for the treatment of MS, we agreed to repay certain amounts based upon the following milestones: (i) 50% of the grant upon the first commercial product sale, (ii) an additional 50% of the grant upon cumulative sales of $10.0 million, (iii) an additional 150% of the grant upon cumulative sales of $50.0 million, and (iv) an additional 200% of the grant upon cumulative sales of $100.0 million, with the maximum repayment equal to 450% of the grant funding if all milestones are achieved. Additionally, if NMSS has not yet received repayments equal in the aggregate to 300% of the grant funding, then upon the closing of any of the following events we will repay 300% of the grant funding, or $1.0 million, less any amounts previously paid by us: (i) sale of all or substantially all of our assets and business, (ii) a public offering that occurs more than twelve months after completion of the biomarker research, (iii) sale of any portion of our assets and business including CNM-Au8 for the treatment of MS, (iv) exclusive licensing of our intellectual property claiming CNM-Au8 for the treatment of MS, and (v) a collaboration with a third-party to develop CNM-Au8 for the treatment of MS. As of December 31, 2022, we have not met any of the above milestones and the biomarker research has not been completed. We accounted for this contingency in accordance with ASC 450, Contingencies. Management has assessed the likelihood of occurrence of each contingent event as less than probable and therefore no contingent liability is recognized in the consolidated balance sheets. Management’s estimate of the possible range of loss is between the minimum and maximum repayment amounts, equal to 50% and 450% of the grant funding, or approximately $0.2 million and $1.5 million, respectively. However, it is at least reasonably possible that Management’s estimate of the probability of occurrence of each contingent event and the possible range of loss will change in the near term.

Note 12 - Income Taxes

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Text Block]

Note 12. Income Taxes

The components of loss before income taxes for the years ended December 31, 2022 and 2021 were as follows:

	*Year Ended December 31,*
(in thousands)	*2022*			*2021*
United States	$	(26,941	)	$	(6,269	)
Foreign		(2,977	)		(3,899	)
Net loss before income taxes	$	(29,918	)	$	(10,168	)

Income tax expense (benefit) for the years ended December 31, 2022 and 2021 was as follows:

(in thousands)	*2022*		*2021*
Current tax expense:
Federal	$	—	$	—
State		—		—
Foreign		—		(146	)
Total current tax expense		—		(146	)

Deferred tax expense:
Federal		—		—
State		—		—
Foreign		—		(282	)
Total deferred tax expense		—		(282	)
Total income tax expense	$	—	$	(428	)

A reconciliation of income tax computed at the U.S. federal statutory rate of 21.00% to expense for income taxes for the years ended December 31, 2022 and 2021 was as follows:

(in thousands)	*2022*			*2021*
Income tax expense (benefit) at federal statutory rate	$	(6,282	)	$	(2,135	)
State income taxes (net of federal benefit)		(320	)		(1,690	)
Change in fair value of common stock warrant liability		(36	)		(206	)
Change in fair value of contingent earn-outs		(3,029	)		(7,884	)
Research and development tax credits		(423	)		(640	)
Stock compensation		(170	)		(462	)
Foreign rate differential		(261	)		(157	)
Other		67			625
Change in valuation allowance		10,454			12,121
Income tax expense	$	—		$	(428	)

Our effective tax rate was 0.00% and 4.21% during the years ended December 31, 2022 and 2021, respectively. Significant components of deferred tax assets (liabilities) as of December 31, 2022 and 2021 were as follows:

(in thousands)	*2022*			*2021*
Deferred tax assets (liabilities):
Net operating loss carryforwards	$	30,460		$	26,898
Depreciation and amortization		1,131			1,478
Research and development tax credits		3,808			2,594
Lease liability		1,312			1,158
Right-of-use asset		(999	)		(798	)
Capitalized research and development expenses		4,712			—
Non-qualified stock options and restricted stock awards		3,849			2,815
Accrued compensation		396			74
Other		20			19
Total deferred tax assets (liabilities)		44,689			34,238
Less: valuation allowance		(44,689	)		(34,238	)
Net deferred tax assets (liabilities)	$	—		$	—

In assessing the realizability of deferred tax assets, we consider whether it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during periods in which those temporary differences become deductible. We consider the scheduled reversal of deferred tax liabilities, projected future taxable income, carry back opportunities and tax planning strategies in making the assessment. We believe it is more likely than not that we will not realize the benefits of these deductible differences and have applied a full valuation allowance against them.

We have federal and state net operating losses (“NOLs”) of approximately $127.2 million and $78.4 million as of December 31, 2022, respectively that, subject to limitation, may be available in future tax years to offset taxable income. Of the available federal NOLs, approximately $93.7 million can be carried forward indefinitely but utilization is limited to 80% of our taxable income in any given tax year based on current federal tax laws. The remaining balance of $33.5 million will begin to expire after 2034. Of the available state NOLs, approximately $65.5 million can be carried forward indefinitely but utilization is limited to 80% of our taxable income in any given tax year based on current tax laws. The remaining balance of $12.9 million will begin to expire after 2032. Additionally, we had approximately $3.8 million of research and development credit carryforwards that will begin to expire after 2034 if not utilized.

Under the provisions of Section 382 of the Internal Revenue Code of 1986, substantial changes in our ownership may result in limitations on the amount of NOL carryforwards and research and development credits that can be utilized in future years. NOL carryforwards and research and development credits are subject to examination in the year they are utilized regardless of whether the tax year in which they are generated has been closed by statute. The amount subject to disallowance is limited to the amount utilized. Accordingly, we may be subject to examination for prior NOLs and credits generated as such tax attributes are utilized.

We have not recorded any amounts for unrecognized tax benefits as of December 31, 2022 and 2021. We recognize interest and penalties related to income tax matters in income tax expense. We have no accrual of interest and penalties on the consolidated balance sheets and have not recognized interest and penalties in the consolidated statements of operations and comprehensive loss for the years ended December 31, 2022 and 2021.

We are subject to taxation in the United States, Australia, Netherlands, and various state jurisdictions. Our tax returns from 2014 to present are subject to examination by the United States and state authorities due to the carry forward of unutilized net operating losses and research and development credits. There are currently no pending examinations.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI https://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Note 13 - Benefit Plans

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Text Block]

Note 13. Benefit Plans

401(k) Plan

Our 401(k) plan is a deferred salary arrangement under Section 401(k) of the Internal Revenue Code. Under the 401(k) plan, participating U.S. employees may defer a portion of their pretax earnings, up to the U.S. Internal Revenue Service annual contribution limit. We match 100% of a participating employee’s deferral contributions up to 3% of annual compensation, limited to $4,500 of matching contributions. Our contributions to the 401(k) plan totaled $0.2 million and $0.2 million for the years ended December 31, 2022 and 2021, respectively.

2020 Stock Plan

The 2020 Stock Plan reserves 12,000,000 shares of Common Stock for issuance thereunder, all of which may be issued pursuant to incentive stock options or any other type of award under the 2020 Stock Plan. Selected employees, officers, directors, and consultants of the Company are eligible to participate in the 2020 Stock Plan. The purpose of the 2020 Stock Plan is to enable us to offer competitive equity compensation packages in order to attract and retain talent and align the interests of management with those of stockholders. The 2020 Stock Plan is administered by the Board. The exercise prices, vesting periods, and other restrictions are determined at the discretion of the Board, except that the exercise price per share of stock options may not be less than 100% of the fair market value of the Common Stock on the date of grant. Stock options expire ten years after the grant date unless the Board sets a shorter term. Stock options granted to employees, officers, directors, and consultants generally vest over a four-year period. If an option or award granted under the 2020 Stock Plan expires, or is terminated, forfeited, repurchased, or cancelled, the unissued shares subject to that option or award shall again be available under the 2020 Stock Plan. As of December 31, 2022, the Board has granted a total of 10,944,777 stock options and rights to restricted stock awards under the 2020 Stock Plan, and 1,055,223 shares remained available for future grant.

2014 Stock Plan

The 2014 Stock Plan is administered by the Board. Stock options granted under the 2014 Stock Plan expire ten years after the grant date. Stock options and restricted stock awards granted to employees, officers, directors, and consultants generally vest over a four-year period. Effective as of the closing of the Reverse Recapitalization, no additional awards may be granted under the 2014 Stock Plan and as a result, if any award granted under the 2014 Stock Plan expires, or is terminated, forfeited, repurchased, cancelled, or tendered by a participant to us to exercise an award, the unissued shares subject to that award will not be available for future awards.

Stock-Based Compensation Expense

Stock-based compensation expense recorded in research and development expense and general and administrative expense for the years ended December 31, 2022 and 2021 was as follows:

	*Year Ended December 31,*
(in thousands)	*2022*		*2021*
General and administrative	$	5,248	$	7,553
Research and development		3,265		4,831
Total stock-based compensation expense	$	8,513	$	12,384

Stock-based compensation expense by award type for the years ended December 31, 2022 and 2021 was as follows:

	Year Ended December 31,
(in thousands)	2022		2021
Stock options	$	8,513	$	4,944
Restricted stock awards		—		7,440
Total stock-based compensation expense	$	8,513	$	12,384

Stock Options

Outstanding stock options and related activity for the year ended December 31, 2022 was as follows:

(in thousands, except share, per share, and term data)	Number of Options			Weighted Average Exercise Price Per Share		Weighted Average Remaining Term (Years)		Intrinsic Value
Outstanding – December 31, 2021		10,395,027			3.35		6.32	$	21,082
Granted		6,371,537			1.96		9.54		—
Exercised		(1,219,360	)		0.25		—		915
Forfeited		(286,907	)		5.46		—		—
Outstanding – December 31, 2022		15,260,297		$	2.98		7.28	$	2,348
Vested and exercisable – December 31, 2022		7,097,942		$	2.64		5.06	$	2,348
Vested, exercisable or expected to vest – December 31, 2022		15,260,297		$	2.98		7.28	$	2,348

As of December 31, 2022 and 2021, we had approximately $18.2 million and $18.3 million, respectively, of unrecognized stock-based compensation costs related to non-vested stock options which is expected to be recognized over a weighted-average period of 2.58 years and 3.05 years, respectively.

Stock options are valued using a Black-Scholes option-pricing model. Due to the limited trading history of our Common Stock, the expected volatility is derived from the average historical stock volatilities of several unrelated comparable public companies within our industry, over a period equivalent to the expected term of the stock option grants. The risk-free interest rate for periods within the contractual life of the stock options is based on the U.S. Treasury yield curve in effect on the grant date. The expected dividend is assumed to be zero as we have never paid a dividend and have no plans to do so. The expected term represents the period the stock options are expected to be outstanding. For stock options that are considered to be in the ordinary course, we determine the expected term using the simplified method, which considers the term to be the average of the time-to-vesting and the contractual life of the stock options. For other stock option grants, we estimate the expected term using historical data on employee exercises and post-vesting employment termination behavior, while also considering the contractual life of the award.

The assumptions used to calculate the fair value of stock options granted during the year ended December 31, 2022 and 2021 were as follows:

	*2022*			*2021*
Expected stock price volatility		89.57% – 99.77%			87.40% – 91.51%
Risk-free interest rate		1.65% – 4.31%			0.72% – 1.34%
Expected dividend yield		0.00	%		0.00	%
Expected term of options (in years)		5.00 – 6.98			6.00

The weighted-average grant-date fair value of stock options granted during the year ended December 31, 2022 and 2021 was $1.49 and $5.49, respectively.

Restricted Stock Awards

In connection with the Reverse Recapitalization, the following rights to restricted stock awards were granted to various employees and non-employee directors:

●

454,781 shares which complement the Milestone 1 earn-out share entitlement of Clene Nanomedicine stockholders and vests based on the same market condition (see Note 3), subject to the holder’s continuous employment. The grant-date fair value of these awards, using a Monte Carlo valuation model, was $4.3 million. Based on the outcome of the market condition as of the December 31, 2022 and 2021 measurement dates, no shares were vested.

●

341,090 shares which complement the Milestone 2 earn-out share entitlement of Clene Nanomedicine stockholders and vests based on the same market condition (see Note 3), subject to the holder’s continuous employment through such vesting date. The grant-date fair value of these awards, using a Monte Carlo valuation model, was $3.5 million. Based on the outcome of the market condition as of the December 31, 2022 and 2021 measurement dates, no shares were vested.

Outstanding rights to restricted stock awards and related activity for the year ended December 31, 2022 was as follows:

	Number of Restricted Stock Awards			Weighted Average Grant Date Fair Value
Unvested balance – December 31, 2021		916,603		$	10.00
Converted to shares of Common Stock upon vesting		(145,439	)		—
Forfeited		(2,025	)		9.84
Unvested balance – December 31, 2022		769,139		$	9.84

As of December 31, 2022 and 2021, there was no unrecognized compensation cost related to unvested rights to restricted stock awards.

Note 14 - Fair Value

12 Months Ended

Dec. 31, 2022

Fair Value Disclosures [Text Block]

Note 14. Fair Value

Cash and cash equivalents are carried at fair value. Financial instruments, including accounts receivable, accounts payable, and accrued expenses are carried at cost, which approximates fair value given their short-term nature. Marketable securities, the Avenue Warrant, and the Contingent Earn-outs are carried at fair value. The 2019 MD Loan and the 2019 Cecil Loan are carried at the greater of principal plus accrued interest or the value of Phantom Shares, which approximates fair value. The 2021 Avenue Loan, including the convertible notes payable and Avenue Conversion Feature, the 2022 MD Loan, and the 2022 DHCD Loan are carried at amortized cost, which approximates fair value due to our credit risk and market interest rates.

Financial Instruments with Fair Value Measurements on a Recurring Basis

The fair value hierarchy for financial instruments measured at fair value on a recurring basis as of December 31, 2022 is as follows:

	*December 31, 2022*
(in thousands)	*Level 1*		*Level 2*		*Level 3*		*Total*
Cash equivalents
Money market funds	$	14,317	$	—	$	—	$	14,317
Marketable securities
Commercial paper		—		3,482		—		3,482
Corporate debt securities		—		1,501		—		1,501
Clene Nanomedicine contingent earn-out liability		—		—		2,264		2,264
Initial Stockholders contingent earn-out liability		—		—		291		291

The fair value hierarchy for financial instruments measured at fair value on a recurring basis as of December 31, 2021 is as follows:

	December 31, 2021
(in thousands)	Level 1		Level 2		Level 3		Total
Notes payable	$	736	$	—	$	—	$	736
Common stock warrant liability		—		—		474		474
Clene Nanomedicine contingent earn-out liability		—		—		18,100		18,100
Initial Stockholders contingent earn-out liability		—		—		2,317		2,317

There were no transfers between Level 1, Level 2, or Level 3 during any of the periods above.

Changes in the fair value of our Level 3 financial instruments for the year ended December 31, 2022 were as follows:

(in thousands)	*Common Stock Warrant Liability*			*Clene Nanomedicine Contingent Earn-out*			*Initial Stockholders Contingent Earn-out*
Balance – December 31, 2021	$	474		$	18,100		$	2,317
Change in fair value		—			(15,836	)		(2,026	)
Reclassification from liability to equity		(305	)		—			—
Extinguishment of instrument		(169	)		—			—
Balance – December 31, 2022	$	—		$	2,264		$	291

Changes in the fair value of our Level 3 financial instruments for the year ended December 31, 2021 were as follows:

(in thousands)	Common Stock Warrant Liability			Clene Nanomedicine Contingent Earn-out			Initial Stockholders Contingent Earn-out
Balance – December 31, 2020	$	—		$	52,053		$	5,906
Initial fair value of instrument		1,457			—			—
Change in fair value		(983	)		(33,953	)		(3,589	)
Balance – December 31, 2021	$	474		$	18,100		$	2,317

Valuation of Notes Payable and Convertible Notes Payable

As of December 31, 2022 and 2021, the carrying value of the 2019 MD Loan was $0.7 million (Level 3) and $0.6 million (Level 1) respectively; and the carrying value of the 2019 Cecil Loan was $0.1 million (Level 3) and $0.1 million (Level 1), respectively. In all periods presented, the 2019 MD Loan and 2019 Cecil Loan were recorded at principal plus accrued interest in the consolidated balance sheets as it was greater than the value of the Phantom Shares.

As of December 31, 2022, the amortized cost of the 2021 Avenue Loan was $19.3 million (Level 3), which included (i) notes payable carried at $14.5 million, of which $6.4 million was classified in current liabilities and $8.1 million was classified as non-current; and (ii) convertible notes payable carried at $4.8 million. As of December 31, 2021, the amortized cost of the 2021 Avenue Loan was $18.4 million (Level 3), which included (i) notes payable carried at $13.8 million; and (ii) convertible notes payable carried at $4.6 million. The Avenue Conversion Feature did not meet the requirements for separate accounting as a derivative instrument.

As of December 31, 2022, the amortized cost of the 2022 MD Loan was $0.7 million (Level 3). As of December 31, 2021, the 2022 MD Loan was not outstanding.

As of December 31, 2022, the amortized cost of the 2022 DHCD Loan was $5.0 million (Level 3). The DHCD Conversion Feature did not meet the requirements for separate accounting as a derivative instrument. As of December 31, 2021, the 2022 DHCD Loan was not outstanding.

Valuation of the Common Stock Warrant Liability

The common stock warrant liability associated with the Avenue Warrant was comprised of the Tranche 1 Warrant and the contingently issuable Tranche 2 Warrant to purchase shares of Common Stock, which were classified as liabilities and recorded at fair value at issuance. As we did not complete a bona fide round of equity financing by March 31, 2022, the exercise price and underlying shares of the Tranche 1 warrant became fixed and therefore qualified for equity classification. We remeasured the Tranche 1 warrant liability to fair value as of March 31, 2022 and recognized the change in fair value in the consolidated statements of operations and comprehensive loss and the Tranche 1 warrant liability was reclassified to additional paid-in-capital. As Tranche 2 of the 2021 Avenue Loan was not drawn as of December 31, 2022, the common stock warrant liability associated with Tranche 2 was extinguished and we recognized income of $0.2 million in the consolidated statements of operations and comprehensive loss.

The estimated fair value was determined using a Black-Scholes option-pricing model. The unobservable inputs to the Black-Scholes option-pricing model as of December 31, 2021 were as follows:

	2021
Expected stock price volatility		105.00	%
Risk-free interest rate		1.20	%
Expected dividend yield		0.00	%
Expected term (in years)		3.89 –4.39
Probability of drawing Tranche 2		50.00	%

Valuation of the Contingent Earn-Out Liabilities

The Clene Nanomedicine and Initial Stockholders Contingent Earn-outs were recorded at fair value at the closing of the Reverse Recapitalization and are remeasured at each reporting period. As of December 31, 2022 and 2021, Clene Nanomedicine’s common stockholders were entitled to receive up to 5,842,334 shares of Common Stock and the Initial Stockholders were entitled to receive up to 750,000 shares of Common Stock. As of December 31, 2021, we did not achieve Milestone 3 and the 2,503,851 Milestone 3 Contingent Earn-out shares were cancelled (see Note 3).

The estimated fair value of the Contingent Earn-outs is determined using a Monte Carlo valuation model in order to simulate the future path of our stock price over the earn-out periods. The carrying amount of the liabilities may fluctuate significantly and actual amounts paid may be materially different from the liabilities’ estimated value. The unobservable inputs to the Monte Carlo valuation model were as follows:

	*2022*			*2021*
Expected stock price volatility		115.00	%		105.00	%
Risk-free interest rate		4.20	%		1.10	%
Expected dividend yield		0.00	%		0.00	%
Expected term (in years)		3.00			4.00

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Note 15 - Common Stock

12 Months Ended

Dec. 31, 2022

Stockholders' Equity Note Disclosure [Text Block]

Note 15. Common Stock

As of December 31, 2022 and 2021, our amended and restated certificate of incorporation authorized us to issue 150,000,000 shares of Common Stock, par value $0.0001 per share, and 1,000,000 shares of preferred stock, par value $0.0001 per share.

Our common stockholders are entitled to one vote per share and to notice of any stockholders’ meeting. Voting, dividend, and liquidation rights of the holders of Common Stock are subject to the prior rights of holders of all classes of stock and are qualified by the rights, powers, preferences, and privileges of the holders of preferred stock. No distributions shall be made with respect to Common Stock until all declared dividends to preferred stock have been paid or set aside for payment. Common Stock is not redeemable at the option of the holder.

As of December 31, 2022 and 2021, our Common Stock issued and outstanding was 74,759,591 and 62,312,097 shares, respectively, and there were no shares of preferred stock issued or outstanding.

Equity Offerings

Prior to the completion of the Reverse Recapitalization, we entered into subscription agreements with various investors (the “2020 PIPE”) for the sale and issuance of 2,239,500 shares of Common Stock at a price of $10.00 per share, generating net proceeds of $22.2 million. In addition, investors in the 2020 PIPE also received warrants (the “PIPE Warrants”) to purchase a number of shares equal to one-half (1/2) of the number of 2020 PIPE shares, totaling 1,119,750 shares of Common Stock, at $0.01 per share and subject to a 180-day holding period. Between July 1, 2021 and December 20, 2021, the PIPE Warrants were exercised in full for 1,119,750 shares of Common Stock. We received cash proceeds of $11,198.

In May 2021, we entered into subscription agreements with various investors (the “2021 PIPE”) for the sale and issuance of 960,540 shares of Common Stock at a price of $9.63 per share, generating net proceeds of $9.3 million.

In October 2022, we entered into securities purchase agreement with certain of our existing stockholders, including stockholders affiliated with our directors, pursuant to which we sold, in a registered direct offering (the “Offering”), 10,723,926 shares of Common Stock at a sale price of $1.01 per share. The Offering was made without a placement agent, underwriter, broker or dealer and the we did not pay underwriting discounts or commissions. The aggregate gross proceeds were $10.8 million before expenses. The total expenses of the Offering were $25,000. The Offering was made pursuant to our registration statement on Form S-3 (file number 333-264299), which was declared effective by the SEC on April 26, 2022, and our prospectus supplement relating to the Offering.

At-the-Market Facility

In April 2022, we entered into an Equity Distribution Agreement (the “ATM Facility”) with Canaccord Genuity LLC and Oppenheimer & Co. Inc., as placement agents (the “Placement Agents”). In December 2022, we amended the ATM Facility and removed Oppenheimer & Co. Inc. as a Placement Agent. In accordance with the terms of the ATM Facility, we may offer and sell shares of Common Stock having an aggregate offering price of up to $50.0 million from time to time through the Placement Agent. The issuance and sale of Common Stock, if any, by us under the ATM Facility will be made pursuant to our registration statement on Form S-3 (file number 333-264299), which was declared effective by the Securities and Exchange Commission on April 26, 2022, and our prospectus supplement relating to the offering.

Subject to terms of the ATM Facility, the Placement Agent is not required to sell any specific number or dollar amount of Common Stock but will act as our placement agent, using commercially reasonable efforts to sell, on our behalf, all of the Common Stock requested by us to be sold, consistent with the Placement Agent’s normal trading and sales practices, on terms mutually agreed between the Placement Agent and us. The Placement Agent will be entitled to compensation under the terms of the ATM Facility at a fixed commission rate of 3.0% of the gross proceeds from each issuance and sale of Common Stock, if any. During the year ended December 31, 2022, we sold 358,769 shares of Common Stock under the ATM Facility, generated gross proceeds of $0.8 million, and paid commissions of $23,000.

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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Note 16 - Net Loss Per Share Attributable to Common Stockholders

12 Months Ended

Dec. 31, 2022

Earnings Per Share [Text Block]

Note 16. Net Loss Per Share

The computation of basic and diluted net loss per share attributable to common stockholders for the years ended December 31, 2022 and 2021 was as follows:

	*Year Ended December 31,*
(in thousands, except share and per share data)	*2022*			*2021*
Numerator:
Net loss attributable to common stockholders	$	(29,918	)	$	(9,740	)
Denominator:
Weighted average common shares outstanding		65,204,663			61,558,455
Net loss per share attributable to common stockholders – basic and diluted	$	(0.46	)	$	(0.16	)

The following shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the years ended December 31, 2022 and 2021 because they were antidilutive, out-of-the-money, or the issuance of such shares is contingent upon certain conditions which were not satisfied by the end of the period:

	*Year Ended December 31,*
	*2022*		*2021*
Convertible notes payable (see Note 9)		1,732,703		482,703
Common stock warrants (see Note 10)		4,477,045		4,477,045
Options to purchase common stock (see Note 13)		15,260,297		10,395,027
Unvested restricted stock awards (see Note 13)		769,139		916,603
Contingent earn-out shares (see Note 3)		6,592,334		6,592,334
Total		28,831,518		22,863,712

Note 17 - Related Party Transactions

12 Months Ended

Dec. 31, 2022

Note 17. Related Party Transactions

License and Supply Agreements

In August 2018, we entered into a license agreement and exclusive supply agreement (collectively, the “4Life Agreement”) in conjunction with 4Life’s investment in our Series C preferred stock and warrants. Pursuant to the 4Life Agreement, we granted 4Life an exclusive license to sell certain dietary supplements. The term of the exclusive license is five years from the commencement of product sales under the 4Life Agreement, which was in April 2021, with options to renew for additional five-year terms. We provide non-pharmaceutical product to 4Life for development, and 4Life pays royalties of 3% of incremental sales. 4Life is subject to an annual minimum sales requirement. If the minimum sales are unmet, 4Life may pay us an additional fee to maintain exclusivity or have the license converted to non-exclusive. Total revenue under the 4Life Agreement for the years ended December 31, 2022 and 2021 was as follows:

	*Year Ended December 31,*
(in thousands)	*2022*		*2021*
Product revenue from related parties	$	316	$	479
Royalty revenue from related parties		144		153
Total revenue from related parties	$	460	$	632

Registered Direct Offering

In October 2022, we entered into securities purchase agreements with certain affiliated stockholders in the Offering (see Note 15). The affiliated stockholders included directors of Clene Inc. and Clene Nanomedicine, to whom we sold 6,287,129 shares of Common Stock as a sale price of $1.01 per share, for gross aggregate proceeds of $6.4 million. As of December 31, 2022, there were no amounts due from these affiliated stockholders.

Note 18 - Geographic and Segment Information

12 Months Ended

Dec. 31, 2022

Segment Reporting Disclosure [Text Block]

Note 18. Geographic and Segment Information

Geographic Information

Long-lived assets, which were composed of property and equipment, net by location, as of December 31, 2022 and 2021, were as follows:

(in thousands)	*2022*		*2021*
United States	$	10,638	$	5,142
Australia		—		30
Total property and equipment, net	$	10,638	$	5,172

Segment Information

Our operating segment profit measure is segment loss from operations, which is calculated as revenue less cost of revenue, research and development, and general and administrative expenses. Profit and loss information by reportable segment for the years ended December 31, 2022 and 2021 was as follows:

	*Year Ended December 31,*
(in thousands)	*2022*			*2021*
Drugs:
Revenue from external customers	$	—		$	—
Depreciation expense		(974	)		(910	)
Stock compensation expense		8,513			12,384
Loss from operations		(48,769	)		(50,183	)
Supplements:
Revenue from external customers	$	473		$	723
Depreciation expense		(45	)		(45	)
Stock compensation expense		—			—
Income from operations		360			205
Consolidated:
Revenue from external customers	$	473		$	723
Depreciation expense		(1,019	)		(955	)
Stock compensation expense		8,513			12,384
Loss from operations		(48,409	)		(49,978	)

A reconciliation of the total of the reportable segments’ loss from operations to consolidated net loss before income taxes for the years ended December 31, 2022 and 2021 was as follows:

	*Year Ended December 31,*
(in thousands)	*2022*			*2021*
Segment loss from operations	$	(48,409	)	$	(49,978	)
Total other income (expense), net		18,491			39,810
Net loss before income taxes	$	(29,918	)	$	(10,168	)

Segment assets exclude corporate assets, such as cash, restricted cash, and corporate facilities. Total assets by reportable segment as of December 31, 2022 and 2021 were as follows:

(in thousands)	*2022*		*2021*
Total assets:
Drugs	$	20,476	$	12,052
Supplements		386		337
Corporate		23,631		50,674
Consolidated	$	44,493	$	63,063

Additions to long-lived assets were through cash expenditure, accounts payable, and a lease incentive representing an allowance for facility alterations. For the years ended December 31, 2022 and 2021, total additions were as follows:

	Year Ended December 31,
(in thousands)	2022		2021
Drugs	$	6,485	$	1,332
Supplements		—		—
Corporate		—		—
Consolidated	$	6,485	$	1,332

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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Note 19 - Subsequent Events

12 Months Ended

Dec. 31, 2022

Subsequent Events [Text Block]

Note 19. Subsequent Events

At-the-Market Facility

In January through March of 2023, we sold 2,402,519 shares of Common Stock under the ATM Facility and generated gross proceeds of $3.9 million. We paid commissions of $0.1 million to the Placement Agent. The issuance and sale of Common Stock under the ATM Facility is made pursuant to our registration statement of Form S-3 (file number 333-264299), which was declared effective by the SEC on April 26, 2022, and our prospectus supplement relating to the offering.

Equity Line of Credit

On March 3, 2023, we entered into a purchase agreement (the “Purchase Agreement”) with Lincoln Park, pursuant to which Lincoln Park committed to purchase up to $25.0 million of shares of Common Stock at our sole discretion, from time to time over a 36-month period commencing on March 7, 2023. The issuance and sale of Common Stock under the Purchase Agreement is made pursuant to our registration statement on Form S-3 (file number 333-264299), which was declared effective by the SEC on April 26, 2022, and our prospectus supplement relating to the transaction. Pursuant to the Purchase Agreement, we may direct Lincoln Park to purchase up to 75,000 shares of Common Stock (a “Regular Purchase”), which may be increased up to (i) 100,000 shares if the closing price of our Common Stock is not below $1.00, (ii) 150,000 shares if the closing price of our Common Stock is not below $2.00, and (iii) 200,000 shares if the closing price of our Common Stock is not below $4.00. The purchase price for a Regular Purchase is based on the market price of our Common Stock at the time of sale. We may sell shares in excess of a Regular Purchase (an “Accelerated Purchase”) on any day on which we have directed Lincoln Park to purchase the maximum amount allowed for such Regular Purchase, up to the lesser of (i) 300% of the number of shares purchased pursuant to such prior business day Regular Purchase or (ii) 30% of the aggregate shares of our Common Stock traded on Nasdaq on the trading day immediately following the purchase date for such Regular Purchase (subject to certain volume and market price limitations). Additionally, we may sell shares in excess of an Accelerated Purchase (an “Additional Accelerated Purchase”) on any day on which we have directed Lincoln Park to purchase the maximum amount allowed for such Accelerated Purchase, up to the lesser of (i) 300% of the number of shares purchased pursuant to such prior business day Regular Purchase or (ii) 30% of the aggregate shares of our Common Stock traded on Nasdaq during a certain period on the date of the Additional Accelerated Purchase (subject to certain volume and market price limitations). The purchase price for Accelerated Purchases and Additional Accelerated Purchases is equal to 97% of the lesser of (i) the VWAP of our Common Stock on Nasdaq during certain periods on the date of the Accelerated Purchase or Additional Accelerated Purchase or (ii) the closing price of our Common Stock on the date of the Accelerate Purchase or Additional Accelerated Purchase.

We issued 332,668 shares of Common Stock (the “Initial Commitment Shares”) to Lincoln Park as an initial fee for its commitment under the Purchase Agreement and we may issue up to 166,334 additional shares of Common Stock (the “Additional Commitment Shares,” and, together with the Initial Commitment Shares, the “Commitment Shares”) on a pro rata basis upon each purchase by Lincoln Park under the Purchase Agreement. Under applicable Nasdaq listing rules, the total number of shares of Common Stock that we may sell to Lincoln Park is limited to 15,310,115 shares (including the Commitment Shares), representing 19.99% of the outstanding shares of our Common Stock immediately prior to the execution of the Purchase Agreement, unless we (i) first obtain stockholder approval in accordance with applicable Nasdaq listing rules or (ii) the average price paid by Lincoln Park for all shares of Common Stock issued by us under the Purchase Agreement is equal to or greater than $1.2404. The Purchase Agreement prohibits us from directing Lincoln Park to purchase any shares of Common Stock that would result in Lincoln Park having beneficial ownership of greater than 4.99% of our outstanding Common Stock, which Lincoln Park may, in its sole discretion, increase up to 9.99% of our outstanding Common Stock by delivering written notice thereof to us, which shall not be effective until the 61^st day after such written notice is delivered to us. We may terminate the Purchase Agreement at any time, for any reason and without any payment or liability to us, by giving Lincoln Park a termination notice with effect one business date after the notice has been received by Lincoln Park.

Significant Accounting Policies (Policies)	12 Months Ended
Significant Accounting Policies (Policies)	Dec. 31, 2022
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	*Basis of Presentation* The accompanying consolidated financial statements include the accounts of Clene Inc. and our wholly-owned subsidiaries, Clene Nanomedicine, Inc. (“Clene Nanomedicine”), a subsidiary incorporated in Delaware, Clene Australia Pty Ltd (“Clene Australia”), a subsidiary incorporated in Australia, Clene Netherlands B.V. (“Clene Netherlands”), a subsidiary incorporated in the Netherlands, and dOrbital, Inc., a subsidiary incorporated in Delaware, after elimination of all intercompany accounts and transactions. We have prepared the accompanying consolidated financial statements in accordance with United States (“U.S.”) Generally Accepted Accounting Principles (“GAAP”) In the opinion of management, the consolidated financial statements reflect all adjustments, which are normal and recurring in nature, necessary for fair financial statement presentation.
Use of Estimates, Policy [Policy Text Block]	*Use of Estimates* The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, and disclosure of contingent assets and liabilities, and the reported amounts of expenses. We base our estimates on historical experience and various other assumptions that we believe to be reasonable. Actual results may differ from those estimates or assumptions. Estimates are periodically reviewed in light of changes in circumstances, facts, and experience, and any changes in estimates will be recorded in future periods as they develop.
Risk and Uncertainties [Policy Text Block]	*Risks and Uncertainties* The product candidates we develop require approvals from regulatory agencies prior to commercial sales. There can be no assurance that our current and future product candidates will receive the necessary approvals or be commercially successful. If we are denied approval or approval is delayed, it will have a material adverse impact on our business and our consolidated financial statements. We are subject to certain risks and uncertainties and believe that changes in any of the following areas could have a material adverse effect on future financial condition, results of operations, or cash flows: ability to obtain additional financing; regulatory approval and market acceptance of, and reimbursement for, product candidates; performance of third-party CROs and manufacturers upon which we rely; protection of our intellectual property; litigation or claims against us based on intellectual property, patent, product, regulatory, or other factors; and our ability to attract and retain employees necessary to support our growth.
Concentration Risk, Credit Risk, Policy [Policy Text Block]	*Concentrations of Credit Risk* Financial instruments which potentially subject us to significant concentrations of credit risk consist primarily of cash. Our cash is mainly held in financial institutions. Amounts on deposit may at times exceed federally insured limits. We have not experienced any losses on our deposits of cash and do not believe that we are subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.
Cash and Cash Equivalents, Unrestricted Cash and Cash Equivalents, Policy [Policy Text Block]	*Cash and Cash Equivalents* We consider all short-term investments with original maturities of 90 days or less when purchased to be cash equivalents.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]	*Restricted Cash* We classify cash as restricted when it is unavailable for withdrawal or use in our general operating activities. Restricted cash and investments are classified as current and noncurrent on the consolidated balance sheets based on the nature of the restriction. Our restricted cash balance includes contractually restricted deposits related to our corporate credit card.
Marketable Securities, Policy [Policy Text Block]	Marketable Securities Marketable securities are investments with original maturities of more than 90 days when purchased. We do not invest in securities with original maturities of more than one year. Marketable debt securities are considered available-for-sale, and are recorded at fair value, with unrealized gains and losses included as a component of accumulated other comprehensive income (loss) until realized. Realized gains and losses are included in other income (expense), net, on the basis of specific identification. The cost of marketable securities is adjusted for amortization of premiums or accretion of discounts to maturity, and such amortization or accretion is included in other income (expense), net.
Accounts Receivable [Policy Text Block]	*Accounts Receivable* Accounts receivable are stated at invoice value less estimated allowances for sales returns and doubtful accounts. We estimate the allowance for sales returns based on historical percentage of returns over a 12-month trailing average of sales. We continually monitor customer payments and maintain a reserve for expected losses resulting from our customers’ inability to make required payments. We consider factors when estimating the allowance for doubtful accounts such as historical experience, age of the accounts receivable balances, geographic related risks, and economic conditions that may affect a customer’s ability to pay. In cases where there are circumstances that may impair a specific customer’s ability to meet its financial obligations, a specific allowance is recorded against amounts due, thereby reducing the net recognized receivable to the amount reasonably believed to be collectible. Accounts receivable are written off when deemed uncollectible. Recoveries of accounts receivable previously written off are recorded when received. Historically, there have been no sales returns, no written-off accounts receivable, and no allowance for doubtful accounts reducing the balance of the accounts receivable.
Inventory, Policy [Policy Text Block]	*Inventory* Inventory is stated at historic cost on a first-in first-out basis. Our inventory consisted of $29,000 in raw materials and $14,000 in finished goods as of December 31, 2022, and $26,000 in raw material and $15,000 in finished goods as of December 31, 2021. Inventory primarily relates to our Supplements segment.
Property, Plant and Equipment, Policy [Policy Text Block]	*Property and Equipment* Property and equipment are stated at cost less accumulated depreciation. Property and equipment consist of laboratory and office equipment, computer software, and leasehold improvements. Depreciation is calculated using the straight-line method over the estimated economic useful lives of the assets, which are 3-5 years for laboratory equipment, 3-7 years for furniture and fixtures, and 2-5 years for computer software. Leasehold improvements are amortized over the lesser of the estimated lease term or the estimated useful life of the assets. Costs for capital assets not yet placed into service are capitalized as construction in progress and depreciated or amortized in accordance with the above useful lives once placed into service. Upon retirement or sale, the related cost and accumulated depreciation and amortization are removed from the accounts and any resulting gain or loss is included in the consolidated statements of operations and comprehensive loss. Maintenance and repairs that do not improve or extend the lives of the respective assets are expensed to operations as incurred. We capitalize costs to obtain or develop computer software for internal use, including development costs incurred during the software development stage and costs to obtain software for access and conversion of historical data. We also capitalize costs to modify, upgrade, or enhance existing internal-use software that result in additional functionality. We expense costs incurred during the preliminary project stage, training costs, data conversion costs, and maintenance costs.
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]	*Impairment of Long-Lived Assets* Long-lived assets are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors we consider in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative industry or economic trends, and significant changes or planned changes in the use of assets. If an impairment review is performed to evaluate an asset group for recoverability, we compare the forecasted undiscounted cash flows expected to result from the use and eventual disposition of the asset group to its carrying value. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use and eventual disposition of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows using market participant assumptions. We did not record any impairment losses on long-lived assets during the years ended December 31, 2022 and 2021.
Debt, Policy [Policy Text Block]	*Debt* When debt is issued and a derivative is required to be separated (e.g., bifurcated conversion option) or another separate freestanding financial instrument (e.g., warrant) is issued, costs and fees incurred are allocated to the instruments issued (or bifurcated) in proportion to the allocation of proceeds. When some portions of the costs and fees relate to a bifurcated derivative or freestanding financial instrument that is being subsequently measured at fair value, those allocated costs are expensed immediately. Debt discounts, debt premiums, and debt issuance costs related to debt are recorded as deductions that net against the principal value of the debt and are amortized to interest expense over the contractual term of the debt using the effective interest method.
Convertible Notes [Policy Text Block]	*Convertible Debt* In accordance with ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity, when we issue notes with conversion features, we evaluate if the conversion feature is freestanding or embedded. If the conversion feature is embedded, we do not separate the conversion feature from the host contract for convertible notes that are not required to be accounted for as derivatives, or that do not result in substantial premiums accounted for as paid-in-capital. Consequently, we account for a convertible note as a single liability measured at its amortized cost, and we account for a convertible preferred stock as a single equity instrument measured at its historical cost, as long as no other features require separation and recognition as derivatives. If the conversion feature is freestanding, or is embedded and meets the requirements to be separated, we account for the conversion feature as a derivative under ASC 815, Derivatives and Hedging (“ASC 815”). We record the derivative instrument at fair value at inception, and subsequently re-measure to fair value at each reporting period and immediately prior to the extinguishment of the derivative instrument, with any changes recorded in the consolidated statements of operations and comprehensive loss.
Debt With Warrants [Policy Text Block]	*Debt With Warrants* In accordance with ASC 470-20, Debt with Conversion and Other Options, when we issue debt with warrants, we treat the warrants as a debt discount, recorded as a contra-liability against the debt, and amortize the balance over the life of the underlying debt as interest expense in the consolidated statements of operations and comprehensive loss. The offset to the contra-liability is recorded as additional paid-in capital in the consolidated balance sheets if the warrants are not treated as a derivative or liability under ASC 480, Distinguishing Liabilities from Equity (“ASC 480”). Otherwise, the offset to the contra-liability is recorded as a warrant liability in the consolidated balance sheets and is subject to re-measurement to fair value at each balance sheet date, with any changes in fair value recognized in the consolidated statements of operations and comprehensive loss. If the debt is retired early, the associated debt discount is then recognized immediately as interest expense in the consolidated statements of operations and comprehensive loss.
Deferred Charges, Policy [Policy Text Block]	*Deferred Offering Costs* We capitalize certain legal, professional accounting, and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of the equity financing, these costs are recorded in stockholders’ equity as a reduction of proceeds generated as a result of the offering. Should any in-process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the consolidated statements of operations and comprehensive loss. As of December 31, 2022 and 2021, we did not have any deferred offering costs.
Lessee, Leases [Policy Text Block]	*Leases* At inception of a contract, we determine if a contract meets the definition of a lease. We determine if the contract conveys the right to control the use of an identified asset for a period of time. We assess throughout the period of use whether we have both of the following: (i) the right to obtain substantially all of the economic benefits from use of the identified asset, and (ii) the right to direct the use of the identified asset. This determination is reassessed if the terms of the contract are changed. Leases are classified as operating or finance leases based on the terms of the lease agreement and certain characteristics of the identified asset. Right-of-use assets and lease liabilities are recognized at the lease commencement date based on the present value of the future lease payments less any lease incentives received. At the lease commencement date, the discount rate implicit in the lease is used to discount the lease liability if readily determinable. If not readily determinable or leases do not contain an implicit rate, our incremental borrowing rate is used as the discount rate. Our policy is to not record leases with an original term of twelve months or less within the consolidated balance sheets. We recognize lease expense for these short-term leases on a straight-line basis over the lease term in the consolidated statements of operations and comprehensive loss. Certain lease agreements may require us to pay additional amounts for taxes, insurance, maintenance, and other expenses, which are generally referred to as non-lease components. Such variable non-lease components are treated as variable lease payments and recognized in the period in which the obligation for these payments is incurred. Variable lease components and variable non-lease components are not measured as part of the right-of-use asset and liability. Only when lease components and their associated non-lease components are fixed are they accounted for as a single lease component and are recognized as part of a right-of-use asset and liability. Total contract consideration is allocated to the fixed lease and non-lease component. This policy election applies consistently to all asset classes under lease agreements. Leases may contain clauses for renewal at our option. Payments to be made in option periods are recognized as part of the right-of-use lease assets and lease liabilities when it is reasonably certain that the option to extend the lease will be exercised, or is not at our option. We determine whether the reasonably certain threshold is met by considering contract-, asset-, market-, and entity-based factors. In the consolidated statements of operations and comprehensive loss, operating lease expense, which is recognized on a straight-line basis over the lease term, and the amortization of finance lease right-of-use assets, which are included in property and equipment and depreciated, are included in research and development or general and administrative expenses consistent with the leased assets’ primary use. Accretion on the liabilities for finance leases is included in interest expense.
Contingent Earnout [Policy Text Block]	*Contingent Earn-Out Liabilities* In connection with the Reverse Recapitalization, certain stockholders are entitled to receive additional shares of Clene Inc. common stock, par value $0.0001 (“Common Stock”) (the “Contingent Earn-outs”) upon us achieving certain milestones (see Note 3). In accordance with Accounting Standards Codification (“ASC”) 815, Derivatives and Hedging (“ASC 815”), the Contingent Earn-outs are not indexed to our own stock and therefore are accounted for as a liability at the Reverse Recapitalization date and subsequently remeasured at each reporting date with changes in fair value recorded as a component of other income (expense), net.
Common Stock Warrants [Policy Text Block]	*Common Stock Warrants* We account for common stock warrants as either equity-classified instruments or liability-classified instruments based on an assessment of the warrant terms and applicable authoritative guidance. The assessment considers whether the warrants are freestanding financial instruments pursuant to ASC 480, meet the definition of a liability pursuant to ASC 480, and whether the warrants meet all of the requirements for equity classification under ASC 815, including whether the warrants are indexed to our Common Stock, among other conditions for equity classification. This assessment, which requires the use of professional judgment, is conducted at the time of warrant issuance and, for liability-classified warrants, at each reporting period end date while the warrants are outstanding.
Revenue from Contract with Customer [Policy Text Block]	*Revenue Recognition* Under ASC 606, Revenue from Contracts with Customers (“ASC 606”), an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. We only apply the five-step model to contracts when it is probable that we will collect the consideration to which we are entitled in exchange for the goods or services we transfer to the customer. Once a contract is determined to be within the scope of ASC 606 at contract inception, we review the contract to determine which performance obligations we must deliver, and which performance obligations are distinct. We recognize as revenue the amount of the transaction price that is allocated to each performance obligation when that performance obligation is satisfied or as it is satisfied. We typically satisfy our performance obligations via delivery of dietary supplements to the customer. Payments are due upon receipt for commercial transactions, or a prepayment is collected for online retail sales. Our revenue during the years ended December 31, 2022 and 2021 was comprised of sales of dietary supplements and royalties from sales of dietary supplements.
Government Assistance [Policy Text Block]	*Grant Funding* We may submit applications to receive grant funding from governmental and non-governmental entities. We account for grants by analogizing to the grant accounting model under IAS 20, Accounting for Government Grants and Disclosure of Government Assistance (“IAS 20”). We recognize grant funding without conditions or continuing performance obligations, including certain research and development tax credits, as other income in the consolidated statements of operations and comprehensive loss. We accrue certain research and development tax credits receivable in other current assets (see Note 5) in the consolidated balance sheets in an amount equal to the qualifying expenses incurred in each period multiplied by the applicable reimbursement percentage and we recognize other income in the consolidated statements of operations and comprehensive loss. After submission of our tax returns, we receive a cash refund of certain research and development tax credits and relieve the receivable. We recognize grant funding with conditions or continuing performance obligations as a reduction in research and development expenses in the consolidated statements of operations and comprehensive loss in the period during which the related qualifying expenses are incurred and as the conditions or performance obligations are fulfilled. Any amount received in advance of fulfilling such conditions or performance obligations is recorded in accrued liabilities in the consolidated balance sheets if the conditions or performance obligations are expected to be met within the next twelve months. We recorded grants as a reduction of research and development expenses of $0 and $0.2 million for the years ended December 31, 2022 and 2021, respectively.
Fair Value Measurement, Policy [Policy Text Block]	*Fair Value of Financial Instruments* Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy: Level 1—Inputs based upon quoted market prices for identical assets or liabilities in active markets at the measurement date. Level 2—Observable inputs other than quoted market prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. Level 3—Inputs that are management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. The inputs are unobservable in the market and significant to the instrument’s valuation. We review the fair value hierarchy classification of our applicable assets and liabilities on a quarterly basis. Changes in the observability of valuation inputs may result in a reclassification for certain financial assets or liabilities. Reclassifications impacting all levels of the fair value hierarchy are reported as transfers in or out of the Level 1, 2, or 3 categories as of the beginning of the period during which the reclassifications occur.
Foreign Currency Transactions and Translations Policy [Policy Text Block]	*Foreign Currency Translation and Transactions* Our functional currency is the U.S. dollar. Clene Australia determined its functional currency to be the Australian dollar and Clene Netherlands determined its functional currency to be the Euro. We use the U.S. dollar as our reporting currency for the consolidated financial statements. The results of our non-U.S. dollar based functional currency operations are translated to U.S. dollars at the average exchange rates during the period. Our assets and liabilities are translated using the current exchange rate as of the balance sheet date and stockholders’ equity is translated using historical rates. Adjustments resulting from the translation of the consolidated financial statements of our foreign functional currency subsidiaries into U.S. dollars are excluded from the determination of net loss and are accumulated in a separate component of stockholders’ equity. We also incur foreign exchange transaction gains and losses for purchases denominated in foreign currencies. Foreign exchange transaction gains and losses are included in other income (expense), net, as incurred.
Comprehensive Income, Policy [Policy Text Block]	*Comprehensive Loss* Comprehensive loss includes net loss as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. The only elements of other comprehensive loss in any periods presented were translation of foreign currency denominated balances of Clene Australia and Clene Netherlands to U.S. dollars for consolidation and unrealized loss on available-for-sale securities.
Earnings Per Share, Policy [Policy Text Block]	*Net Loss Per Share Attributable to Common Stockholders* Basic net loss per share attributable to common stockholders is calculated using our weighted-average outstanding common shares. Diluted net loss per share attributable to common stockholders is calculated using our weighted-average outstanding common shares including the dilutive effect of securities as determined under the treasury stock method, except for the dilutive effect of convertible notes payable, which is calculated under the if-converted method, even if the embedded conversion option is out-of-the-money. In periods in which we report a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.
Segment Reporting, Policy [Policy Text Block]	*Segment Information* We have determined that our chief executive officer is the chief operating decision maker (“CODM”). Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the CODM in making decisions regarding resource allocation and assessing performance. We view our operations and manage our business in two operating segments, which are our reportable segments: (1) the development and commercialization of novel clean-surfaced nanotechnology therapeutics (“Drugs”), and (2) the development and commercialization of dietary supplements (“Supplements”).
Income Tax, Policy [Policy Text Block]	*Income Taxes* We account for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in our tax returns. Deferred tax assets and liabilities are determined based on the differences between the financial statement basis and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. We assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. We account for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than-not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, which are considered appropriate as well as the related net interest and penalties.
Share-Based Payment Arrangement [Policy Text Block]	*Stock-Based Compensation* We account for stock-based compensation arrangements using a fair value-based method for costs related to all share-based payments including stock options and stock awards. Stock-based compensation expense is recorded in research and development and general and administrative expenses based on the classification of the work performed by the grantees. The fair value is recognized over the period during which a grantee is required to provide services in exchange for the option award and service-based stock awards, known as the requisite service period (usually the vesting period), on a straight-line basis. For stock awards with market conditions, the fair value is recognized over the period based on the expected milestone achievement dates as the derived service period (usually the vesting period), on a straight-line basis. For stock awards with performance conditions, the grant-date fair value of these awards is the market price on the applicable grant date, and compensation expense will be recognized when the conditions become probable of being satisfied. We recognize a cumulative true-up adjustment once the conditions become probable of being satisfied as the related service period had been completed in a prior period. Stock-based compensation expense is recognized at fair value. We elect to account for forfeitures as they occur, rather than estimating expected forfeitures. We determine the fair value of each share of Common Stock underlying stock-based awards using a Black-Scholes option pricing model based on the closing price of our Common Stock as reported by the Nasdaq Capital Market (“Nasdaq”) on the date of grant. The fair value of stock awards with market conditions are determined using a Monte Carlo valuation model.
Research and Development Expense, Policy [Policy Text Block]	*Research and Development* Research and development costs are charged to expense as incurred. We account for nonrefundable advance payments for goods and services that will be used in future research and development activities as expenses when the goods have been received or when the service has been performed. Research and development expenses consist of costs incurred for the discovery and development of our product candidates. Research and development costs include, but are not limited to, payroll and personnel expenses including stock-based compensation, clinical trial supplies, fees for clinical trial services, consulting costs, and allocated overhead, including rent, equipment, and utilities.
Clinical Trial Accrual [Policy Text Block]	*Clinical Trial Accrual* Our clinical trial accrual process accounts for expenses resulting from obligations under contracts with CROs, consultants, and under clinical site agreements in connection with conducting clinical trials. Clinical trial costs are charged to research and development expense as incurred. The financial terms of these contracts are subject to negotiations, which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided to us under such contracts. We reflect the appropriate clinical trial expense in the consolidated financial statements by matching the appropriate expenses with the period in which services and efforts are expended. In the event advance payments are made to a CRO, the payments will be recorded as a prepaid asset which will be amortized to research and development expense over the period the contracted services are performed. In addition to pass-through costs, we generally incur costs in clinical trials in four distinct groups as follows: CRO Start-Up—These costs include the initial set-up of the clinical trial and usually occur within a few months after the contract has been executed and includes costs which are expensed ratably over the start-up period when such period is identifiable and expensed as incurred when no such period exists. Start-up phase activities include study initiation, site recruitment, regulatory applications, investigator meetings, screening, preparation, pre-study visits, and training. CRO Site and Study Management—These costs include medical and safety monitoring, patient administration and data management. These costs are usually calculated on a per-patient basis and expensed ratably over the treatment period beginning on the date that the patient enrolls. CRO Close-Down and Reporting—These costs include analyzing the data obtained and reporting results, which occurs after patients have ceased treatment and the database of information collected is locked. These costs are expensed as incurred over the course of any close-down and reporting period. Third-Party Contracts—These costs include fees charged by third parties for various support services which are not provided by CROs and include such items as laboratory fees, data quality review costs, and fees incurred for investigational product monitoring and inventory control. These items are expensed ratably over any identifiable service period with the engaged third-party vendors. The CRO contracts generally include pass-through fees including, but not limited to, regulatory expenses, investigator fees, travel costs, and other miscellaneous costs, including shipping and printing fees. We determine accrual estimates through reports from and discussion with applicable personnel and outside service providers as to the progress or state of completion of trials or the services completed. We estimate accrued expenses as of each reporting date in the consolidated financial statements based on the facts and circumstances known to us at that time.
New Accounting Pronouncements, Policy [Policy Text Block]	*Recently Adopted Accounting Pronouncements* In May 2021, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2021-04, Earnings Per Share (Topic 260), Debt—Modifications and Extinguishments (Subtopic 470-50), Compensation—Stock Compensation (Topic 718), and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40). The amendments in this update relate to the recognition and measurement of earnings per share for certain modifications or exchanges of equity-classified written call options or warrants. The guidance was effective for our fiscal year and interim periods within our fiscal year beginning after December 15, 2021. The adoption of this guidance did not have an impact on our consolidated financial statements. In November 2021, the FASB issued ASU 2021-10, Government Assistance (Topic 832): Disclosures by Business Entities about Government Assistance. The amendments in this update add disclosure requirements for transactions with a government that are accounted for by applying a grant or contribution accounting model by analogy, including disclosure about the nature of the transactions, accounting policy, affected line items in the balance sheet and income statement, amounts applicable to each financial statement line item, and significant terms and conditions of the transactions including commitments and contingencies. The guidance was effective for our financial statements issued for annual periods beginning after December 15, 2021 and impacted our disclosures under Note 2—“Grant Funding” related to government grants and certain research and development tax credits, which are accounted for by analogizing to the grant accounting model under IAS 20. **Recent Accounting Pronouncements Not* Yet Adopted*** In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The amendments in this update, among other things, require the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Financial institutions and other organizations will now use forward-looking information to better inform their credit loss estimates. As a smaller reporting company, the guidance is effective for our fiscal years beginning after December 15, 2022. We are currently evaluating the expected impact, if any, of the new guidance as a result of this extended deadline of implementation for smaller reporting companies.

Note 4 - Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2022

Marketable Securities [Table Text Block]

	*December 31, 2022*
(in thousands)	*Amortized Cost*		*Gross Unrealized Gains*		*Gross Unrealized Losses*			*Fair Value*
Commercial paper	$	3,496	$	—	$	(14	)	$	3,482
Corporate debt securities		1,501		—		—			1,501
Total	$	4,997	$	—	$	(14	)	$	4,983

Summary of Proceeds from Sale and Maturity of Available for Sale Securities [Table Text Block]

	Year Ended December 31,
(in thousands)	2022		2021
Proceeds from maturities and calls of marketable securities	$	12,015	$	—
Proceeds from sales of marketable securities	$	7,614		—
Total	$	19,629	$	—

Note 5 - Prepaid Expenses and Other Current Assets (Tables)

12 Months Ended

Dec. 31, 2022

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]

(in thousands)	*2022*		*2021*
Research and development tax credits receivable	$	2,777	$	1,564
Metals to be used in research and development		2,290		2,237
Other		581		404
Total prepaid expenses and other current assets	$	5,648	$	4,205

Note 6 - Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Table Text Block]

(in thousands)	*2022*			*2021*
Lab equipment	$	3,934		$	3,327
Office equipment		177			147
Computer software		459			—
Leasehold improvements		5,677			3,943
Construction in progress		5,664			2,052
		15,911			9,469
Less accumulated depreciation		(5,273	)		(4,297	)
Total property and equipment, net	$	10,638		$	5,172

Depreciation Of Property Plant And Equipment [Table Text Block]

	Year Ended December 31,
(in thousands)	2022		2021
General and administrative	$	229	$	115
Research and development		790		840
Total depreciation expense	$	1,019	$	955

Note 7 - Accrued Liabilities (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Accrued Liabilities [Table Text Block]

(in thousands)	*2022*		*2021*
Accrued compensation and benefits	$	2,007	$	2,049
Accrued CRO and clinical fees		1,297		718
Deferred grant funds		520		520
Other		39		323
Total accrued liabilities	$	3,863	$	3,610

Note 8 - Leases (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Assets Under Finance Lease [Table Text Block]

(in thousands)	*2022*			*2021*
Lab equipment	$	408		$	408
Work in process		228			228
Total		636			636
Less accumulated depreciation		(326	)		(244	)
Net	$	310		$	392

Finance and Operating Lease Liability, Maturity [Table Text Block]

(in thousands)	Finance Leases			Operating Leases
2023	$	96		$	1,051
2024		27			1,171
2025		—			1,202
2026		—			1,231
2027		—			1,129
Thereafter		—			2,786
Total undiscounted cash flows		123			8,570
Less amount representing interest/discounting		(15	)		(2,525	)
Present value of future lease payments		108			6,045
Less lease obligations, current portion		(74	)		(488	)
Lease obligations, long term portion	$	34		$	5,557

Lease, Cost [Table Text Block]

	*Year Ended December 31,*
(in thousands)	*2022*		*2021*
Finance lease costs:
Amortization	$	82	$	82
Interest on lease liabilities		16		27
Operating lease costs		948		429
Short-term lease costs		1		73
Variable lease costs		304		130
Total lease costs	$	1,351	$	741

Schedule of Cash Flow, Supplemental Disclosures, Leases [Table Text Block]

	*Year Ended December 31,*
(in thousands)	*2022*			*2021*
Operating cash flows from operating leases	$	(1,253	)	$	(633	)
Operating cash flows from finance leases	$	(16	)	$	(27	)
Financing cash flows from finance leases	$	(135	)	$	(152	)

Note 9 - Notes Payable and Convertible Notes Payable (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Long-Term Debt Instruments [Table Text Block]

(in thousands, except interest rates)	*Stated Interest Rate*			*2022*			*2021*
Notes payable
Advance Cecil, Inc. (commenced April 2019)		8.00	%	$	130		$	122
Maryland DHCD (commenced February 2019)		8.00	%		654			614
Maryland DHCD (commenced May 2022)		6.00	%		682			—
Avenue Venture Opportunities Fund, L.P. (commenced May 2021)		14.10	%		15,000			15,000
					16,466			15,736
Accrued and unpaid interest					22			—
Less unamortized discount and debt issuance costs					(587	)		(1,252	)
Less notes payable, current portion, net of unamortized discount					(6,418	)		—
Total notes payable, net of current portion				$	9,483		$	14,484

Convertible notes payable
Avenue Venture Opportunities Fund, L.P. (commenced May 2021)		14.10	%	$	5,000		$	5,000
Maryland DHCD (commenced December 2022)		6.00	%		5,000			—
					10,000			5,000
Accrued and unpaid interest					7			—
Less unamortized discount and debt issuance costs					(237	)		(402	)
Total convertible notes payable				$	9,770		$	4,598

Schedule of Maturities of Long-Term Debt [Table Text Block]

(in thousands)	2021 Avenue Loan			2022 MD Loan			2022 DHCD Loan
2023	$	6,667		$	—		$	—
2024		13,333			—			—
2025		—			369			—
2026		—			313			—
2027		—			—			—
Thereafter		—			—			5,000
Subtotal of future principal payments		20,000			682			5,000
Accrued and unpaid interest		—			22			7
Less unamortized discount and debt issuance costs		(747	)		(27	)		(50	)
Total	$	19,253		$	677		$	4,957

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

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Note 10 - Common Stock Warrants (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]

Date Exercisable

Number of
Shares
Issuable

Exercise Price

Exercisable for

Classification

Expiration

December 2020

2,407,500

⁽¹⁾

11.50

Common Stock

Equity

December 2025

December 2020

24,583

⁽²⁾

11.50

Common Stock

Equity

December 2025

December 2020

1,929,111

⁽³⁾

1.97

Common Stock

Equity

April 2023

May 2021

115,851

⁽⁴⁾

8.63

Common Stock

Equity

May 2026

Total

4,477,045

Note 12 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

	*Year Ended December 31,*
(in thousands)	*2022*			*2021*
United States	$	(26,941	)	$	(6,269	)
Foreign		(2,977	)		(3,899	)
Net loss before income taxes	$	(29,918	)	$	(10,168	)

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

(in thousands)	*2022*		*2021*
Current tax expense:
Federal	$	—	$	—
State		—		—
Foreign		—		(146	)
Total current tax expense		—		(146	)

Deferred tax expense:
Federal		—		—
State		—		—
Foreign		—		(282	)
Total deferred tax expense		—		(282	)
Total income tax expense	$	—	$	(428	)

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

(in thousands)	*2022*			*2021*
Income tax expense (benefit) at federal statutory rate	$	(6,282	)	$	(2,135	)
State income taxes (net of federal benefit)		(320	)		(1,690	)
Change in fair value of common stock warrant liability		(36	)		(206	)
Change in fair value of contingent earn-outs		(3,029	)		(7,884	)
Research and development tax credits		(423	)		(640	)
Stock compensation		(170	)		(462	)
Foreign rate differential		(261	)		(157	)
Other		67			625
Change in valuation allowance		10,454			12,121
Income tax expense	$	—		$	(428	)

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

(in thousands)	*2022*			*2021*
Deferred tax assets (liabilities):
Net operating loss carryforwards	$	30,460		$	26,898
Depreciation and amortization		1,131			1,478
Research and development tax credits		3,808			2,594
Lease liability		1,312			1,158
Right-of-use asset		(999	)		(798	)
Capitalized research and development expenses		4,712			—
Non-qualified stock options and restricted stock awards		3,849			2,815
Accrued compensation		396			74
Other		20			19
Total deferred tax assets (liabilities)		44,689			34,238
Less: valuation allowance		(44,689	)		(34,238	)
Net deferred tax assets (liabilities)	$	—		$	—

Note 13 - Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement, Cost by Plan [Table Text Block]

	*Year Ended December 31,*
(in thousands)	*2022*		*2021*
General and administrative	$	5,248	$	7,553
Research and development		3,265		4,831
Total stock-based compensation expense	$	8,513	$	12,384

	Year Ended December 31,
(in thousands)	2022		2021
Stock options	$	8,513	$	4,944
Restricted stock awards		—		7,440
Total stock-based compensation expense	$	8,513	$	12,384

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

(in thousands, except share, per share, and term data)	Number of Options			Weighted Average Exercise Price Per Share		Weighted Average Remaining Term (Years)		Intrinsic Value
Outstanding – December 31, 2021		10,395,027			3.35		6.32	$	21,082
Granted		6,371,537			1.96		9.54		—
Exercised		(1,219,360	)		0.25		—		915
Forfeited		(286,907	)		5.46		—		—
Outstanding – December 31, 2022		15,260,297		$	2.98		7.28	$	2,348
Vested and exercisable – December 31, 2022		7,097,942		$	2.64		5.06	$	2,348
Vested, exercisable or expected to vest – December 31, 2022		15,260,297		$	2.98		7.28	$	2,348

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	*2022*			*2021*
Expected stock price volatility		89.57% – 99.77%			87.40% – 91.51%
Risk-free interest rate		1.65% – 4.31%			0.72% – 1.34%
Expected dividend yield		0.00	%		0.00	%
Expected term of options (in years)		5.00 – 6.98			6.00

Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]

	Number of Restricted Stock Awards			Weighted Average Grant Date Fair Value
Unvested balance – December 31, 2021		916,603		$	10.00
Converted to shares of Common Stock upon vesting		(145,439	)		—
Forfeited		(2,025	)		9.84
Unvested balance – December 31, 2022		769,139		$	9.84

Note 14 - Fair Value (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	*December 31, 2022*
(in thousands)	*Level 1*		*Level 2*		*Level 3*		*Total*
Cash equivalents
Money market funds	$	14,317	$	—	$	—	$	14,317
Marketable securities
Commercial paper		—		3,482		—		3,482
Corporate debt securities		—		1,501		—		1,501
Clene Nanomedicine contingent earn-out liability		—		—		2,264		2,264
Initial Stockholders contingent earn-out liability		—		—		291		291

	December 31, 2021
(in thousands)	Level 1		Level 2		Level 3		Total
Notes payable	$	736	$	—	$	—	$	736
Common stock warrant liability		—		—		474		474
Clene Nanomedicine contingent earn-out liability		—		—		18,100		18,100
Initial Stockholders contingent earn-out liability		—		—		2,317		2,317

Schedule of Derivative Liabilities at Fair Value [Table Text Block]

(in thousands)	*Common Stock Warrant Liability*			*Clene Nanomedicine Contingent Earn-out*			*Initial Stockholders Contingent Earn-out*
Balance – December 31, 2021	$	474		$	18,100		$	2,317
Change in fair value		—			(15,836	)		(2,026	)
Reclassification from liability to equity		(305	)		—			—
Extinguishment of instrument		(169	)		—			—
Balance – December 31, 2022	$	—		$	2,264		$	291

(in thousands)	Common Stock Warrant Liability			Clene Nanomedicine Contingent Earn-out			Initial Stockholders Contingent Earn-out
Balance – December 31, 2020	$	—		$	52,053		$	5,906
Initial fair value of instrument		1,457			—			—
Change in fair value		(983	)		(33,953	)		(3,589	)
Balance – December 31, 2021	$	474		$	18,100		$	2,317

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

	2021
Expected stock price volatility		105.00	%
Risk-free interest rate		1.20	%
Expected dividend yield		0.00	%
Expected term (in years)		3.89 –4.39
Probability of drawing Tranche 2		50.00	%

	*2022*			*2021*
Expected stock price volatility		115.00	%		105.00	%
Risk-free interest rate		4.20	%		1.10	%
Expected dividend yield		0.00	%		0.00	%
Expected term (in years)		3.00			4.00

Note 16 - Net Loss Per Share Attributable to Common Stockholders (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	*Year Ended December 31,*
(in thousands, except share and per share data)	*2022*			*2021*
Numerator:
Net loss attributable to common stockholders	$	(29,918	)	$	(9,740	)
Denominator:
Weighted average common shares outstanding		65,204,663			61,558,455
Net loss per share attributable to common stockholders – basic and diluted	$	(0.46	)	$	(0.16	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	*Year Ended December 31,*
	*2022*		*2021*
Convertible notes payable (see Note 9)		1,732,703		482,703
Common stock warrants (see Note 10)		4,477,045		4,477,045
Options to purchase common stock (see Note 13)		15,260,297		10,395,027
Unvested restricted stock awards (see Note 13)		769,139		916,603
Contingent earn-out shares (see Note 3)		6,592,334		6,592,334
Total		28,831,518		22,863,712

Note 17 - Related Party Transactions (Tables)

12 Months Ended

Dec. 31, 2022

	*Year Ended December 31,*
(in thousands)	*2022*		*2021*
Product revenue from related parties	$	316	$	479
Royalty revenue from related parties		144		153
Total revenue from related parties	$	460	$	632

Note 18 - Geographic and Segment Information (Tables)

12 Months Ended

Dec. 31, 2022

Long-Lived Assets by Geographic Areas [Table Text Block]

(in thousands)	*2022*		*2021*
United States	$	10,638	$	5,142
Australia		—		30
Total property and equipment, net	$	10,638	$	5,172

Reconciliation of Revenue from Segments to Consolidated [Table Text Block]

	*Year Ended December 31,*
(in thousands)	*2022*			*2021*
Drugs:
Revenue from external customers	$	—		$	—
Depreciation expense		(974	)		(910	)
Stock compensation expense		8,513			12,384
Loss from operations		(48,769	)		(50,183	)
Supplements:
Revenue from external customers	$	473		$	723
Depreciation expense		(45	)		(45	)
Stock compensation expense		—			—
Income from operations		360			205
Consolidated:
Revenue from external customers	$	473		$	723
Depreciation expense		(1,019	)		(955	)
Stock compensation expense		8,513			12,384
Loss from operations		(48,409	)		(49,978	)

Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]

	*Year Ended December 31,*
(in thousands)	*2022*			*2021*
Segment loss from operations	$	(48,409	)	$	(49,978	)
Total other income (expense), net		18,491			39,810
Net loss before income taxes	$	(29,918	)	$	(10,168	)

Reconciliation of Assets from Segment to Consolidated [Table Text Block]

(in thousands)	*2022*		*2021*
Total assets:
Drugs	$	20,476	$	12,052
Supplements		386		337
Corporate		23,631		50,674
Consolidated	$	44,493	$	63,063

Additions to Long Lived Assets, Net by Segment [Table Text Block]

	Year Ended December 31,
(in thousands)	2022		2021
Drugs	$	6,485	$	1,332
Supplements		—		—
Corporate		—		—
Consolidated	$	6,485	$	1,332

Note 1 - Nature of Business (Details Textual) - USD ($) $ in Thousands	2 Months Ended	12 Months Ended
	Mar. 13, 2023	Dec. 31, 2022	Dec. 31, 2021	Mar. 03, 2023
Operating Income (Loss), Total		$ (48,409)	$ (49,978)
Retained Earnings (Accumulated Deficit), Total		(193,219)	(163,301)
Cash, Cash Equivalents, and Short-Term Investments, Total		23,300	50,300
Net Cash Provided by (Used in) Operating Activities, Total		(39,011)	(34,624)
Minimum Cash Balance For Loan Covenant		5,000
Proceeds from Issuance of Common Stock		$ 11,460	$ 0
Subsequent Event [Member]
Proceeds from Issuance of Common Stock	$ 3,900
Subsequent Event [Member] \| Equity Purchase Agreement [Member]
Equity Purchase Agreement, Maximum Amount of Shares That Can Be Purchased, Value				$ 25,000

Note 2 - Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2021 USD ($) $ / shares	Dec. 30, 2020 $ / shares
Inventory, Raw Materials, Gross	$ 29,000	$ 26,000
Inventory, Finished Goods, Gross	14,000	15,000
Tangible Asset Impairment Charges, Total	0	0
Deferred Offering Costs	$ 0	$ 0
Common Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares	$ 0.0001	$ 0.0001	$ 0.0001
Research and Development Expense, Total	$ 31,920,000	$ 28,416,000
Number of Operating Segments	2
Grant Funding on Conditional Grants [Member]
Research and Development Expense, Total	$ 0	$ 200,000
Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Furniture and Fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Furniture and Fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	7 years
Computer Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	2 years
Computer Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years

Note 3 - Reverse Recapitalization with Tottenham and Clene Nanomedicine (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Dec. 31, 2020	Dec. 30, 2020	Dec. 31, 2022	Dec. 31, 2021
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.0001	$ 0.0001	$ 0.0001
Stock Issued During Period, Value, New Issues			$ 11,460	$ 9,250
Payments of Stock Issuance Costs			$ (0)	$ 1,901
Reverse Recapitalization [Member]
Stock Issued During Period, Value, New Issues		$ 9,400
Payments of Stock Issuance Costs		5,900
Proceeds from Issuance or Sale of Equity, Total		$ 3,500
Business Combination, Earnout Shares Cancelled (in shares)				2,503,851
Reverse Recapitalization [Member] \| Clene Nanomedicine Contingent Earn-out [Member]
Business Combination, Contingent Earnout Shares, Milestone One (in shares)		3,333,333
Business Combination, Contingent Earnout, Milestone One, Minimum Price (in dollars per share)		$ 15.00
Business Combination, Contingent Earnout, Milestone One, Consecutive Trading Days (Day)		20 days
Business Combination, Contingent Earnout, Milestone One, Trading Day Period (Day)		30 days
Business Combination, Contingent Earnout, Milestone One, Period (Year)		3 years
Business Combination, Contingent Earnout, Milestone One, Change of Control Period (Year)		3 years
Business Combination, Contingent Earnout Shares, Milestone Two (in shares)		2,500,000
Business Combination, Contingent Earnout, Milestone Two, Minimum Price (in dollars per share)		$ 20.00
Business Combination, Contingent Earnout, Milestone Two, Consecutive Trading Days (Day)		20 days
Business Combination, Contingent Earnout, Milestone Two, Trading Day Period (Day)		30 days
Business Combination, Contingent Earnout, Milestone Two, Period (Year)		5 years
Business Combination, Contingent Earnout, Milestone Two, Change of Control Period (Year)		5 years
Business Combination, Contingent Earnout Shares, Milestone Three (in shares)		2,500,000
Total Clene Nanomedicine Contingent Earnout Shares, Increase (in shares)	12,852
Total Clene Nanomedicine Contingent Earnout Shares (in shares)		8,346,185
Reverse Recapitalization [Member] \| Initial Stockholders Contingent Earn-out [Member]
Business Combination, Contingent Earnout Shares, Milestone One (in shares)		375,000
Business Combination, Contingent Earnout Shares, Milestone Two (in shares)		375,000
Reverse Recapitalization [Member] \| LifeSci Capital LLC [Member]
Shares Issued for Payment of Offering Costs (in shares)		644,164

Note 4 - Marketable Securities (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale, Total	$ 4,983	$ 0
Debt Securities Available For Sale Maturity Period (Year)	1 year

Note 4 - Marketable Securities - Available for Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized cost	$ 4,997
Gross unrealized gains	0
Gross unrealized losses	(14)
Fair value	4,983	$ 0
Commercial Paper [Member]
Amortized cost	3,496
Gross unrealized gains	0
Gross unrealized losses	(14)
Fair value	3,482
Corporate Debt Securities [Member]
Amortized cost	1,501
Gross unrealized gains	0
Gross unrealized losses	0
Fair value	$ 1,501

Note 4 - Marketable Securities - Proceeds From Sale and Maturity of Available-for Sale Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Proceeds from maturities and calls of marketable securities	$ 12,015	$ 0
Proceeds from sales of marketable securities	7,614	0
Total	$ 19,629	$ 0

Note 5 - Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Research and development tax credits receivable	$ 2,777	$ 1,564
Metals to be used in research and development	2,290	2,237
Other	581	404
Total prepaid expenses and other current assets	$ 5,648	$ 4,205

Note 6 - Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property and equipment, gross	$ 15,911	$ 9,469
Less accumulated depreciation	(5,273)	(4,297)
Total property and equipment, net	10,638	5,172
Equipment [Member]
Property and equipment, gross	3,934	3,327
Office Equipment [Member]
Property and equipment, gross	177	147
Computer Equipment [Member]
Property and equipment, gross	459	0
Leasehold Improvements [Member]
Property and equipment, gross	5,677	3,943
Construction in Progress [Member]
Property and equipment, gross	$ 5,664	$ 2,052

Note 6 - Property and Equipment, Net - Schedule of Depreciation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Depreciation	$ 1,019	$ 955
General and Administrative Expense [Member]
Depreciation	229	115
Research and Development Expense [Member]
Depreciation	$ 790	$ 840

Note 7 - Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Accrued compensation and benefits	$ 2,007	$ 2,049
Accrued CRO and clinical fees	1,297	718
Deferred grant funds	520	520
Other	39	323
Total accrued liabilities	$ 3,863	$ 3,610

Note 8 - Leases (Details Textual) $ in Thousands	12 Months Ended
Note 8 - Leases (Details Textual) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Feb. 28, 2022 USD ($)	Sep. 30, 2021 USD ($)
Operating Lease, Right-of-Use Asset	$ 4,602	$ 3,250	$ 2,300
Operating Lease, Liability, Total	6,045		2,300
Operating Lease, Right-of-use Asset, Terminated			600
Operating Lease, Liability, Terminated			$ 1,000
Gain (Loss) on Contract Termination	$ 420	$ 0
Operating Lease, Weighted Average Discount Rate, Percent	9.60%	9.60%
Operating Lease, Weighted Average Remaining Lease Term (Year)	7 years 3 months 18 days	8 years 1 month 6 days
Finance Lease, Weighted Average Discount Rate, Percent	10.20%	8.80%
Finance Lease, Weighted Average Remaining Lease Term (Year)	1 year 2 months 12 days	1 year 10 months 24 days
Lease for Laboratory Space [Member]
Operating Lease, Right-of-Use Asset				$ 2,400
Operating Lease, Liability, Total				2,400
Incentive to Lessee				$ 1,000
Lease Incentive Recorded, Construction in Progress	$ 1,000	$ 500
Lessee, Operating Lease, Term of Contract (Year)				10 years
Lessee, Operating Lease, Number of Renewals				2
Lessee, Operating Lease, Renewal Term (Year)				5 years

Note 8 - Leases - Assets Recorded Under Finance Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Finance lease asset, gross	$ 636	$ 636
Less accumulated depreciation	(326)	(244)
Net	310	392
Equipment [Member]
Finance lease asset, gross	408	408
Construction in Progress [Member]
Finance lease asset, gross	$ 228	$ 228

Note 8 - Leases - Maturity Analysis of Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Feb. 28, 2022	Dec. 31, 2021
2023, finance leases	$ 96
2023, operating leases	1,051
2024, finance leases	27
2024, operating leases	1,171
2025, finance leases	0
2025, operating leases	1,202
2026, finance leases	0
2026, operating leases	1,231
2027, finance leases	0
2027, operating leases	1,129
Thereafter, finance leases	0
Thereafter, operating leases	2,786
Total undiscounted cash flows, finance leases	123
Total undiscounted cash flows, operating leases	8,570
Less amount representing interest/discounting, finance leases	(15)
Less amount representing interest/discounting, operating leases	(2,525)
Present value of future lease payments, finance leases	108
Present value of future lease payments, operating leases	6,045	$ 2,300
Less lease obligations, current portion, finance leases	74		$ 146
Less lease obligations, current portion, operating leases	488		347
Lease obligations, long term portion, finance leases	34		97
Lease obligations, long term portion, operating leases	$ 5,557		$ 4,370

Note 8 - Leases - Components of Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Amortization	$ 82	$ 82
Interest on lease liabilities	16	27
Operating lease costs	948	429
Short-term lease costs	1	73
Variable lease costs	304	130
Total lease costs	$ 1,351	$ 741

Note 8 - Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating cash flows from operating leases	$ (1,253)	$ (633)
Operating cash flows from finance leases	(16)	(27)
Payments of finance lease obligations	$ (135)	$ (152)

Note 9 - Notes Payable and Convertible Notes Payable (Details Textual)			1 Months Ended				5 Months Ended	12 Months Ended
	Apr. 30, 2019 USD ($)	Feb. 28, 2019 USD ($)	Dec. 31, 2022 USD ($) $ / shares shares	May 31, 2022 USD ($)	Sep. 30, 2021 USD ($)	May 31, 2021 USD ($) $ / shares shares	Sep. 30, 2021 USD ($)	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($)	May 31, 2020 USD ($)
Proceeds from Notes Payable, Total								$ 5,695,000	$ 20,000,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) \| shares			4,477,045					4,477,045
Convertible Notes Payable [Member]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total			$ 237,000					$ 237,000	402,000
Warrants Issued with 2021 Avenue Loan [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) \| shares						115,851
Avenue [Member] \| Warrants Issued with 2021 Avenue Loan [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) \| shares						115,851
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares						$ 8.63
The 2019 MD Loan [Member] \| Department of Housing and Community Development [Member]
Debt Instrument, Face Amount		$ 500,000
Debt Instrument, Interest Rate, Stated Percentage		8.00%
Debt Instrument, Convertible, Number of Equity Instruments		119,907
Interest Expense, Debt, Total								40,000
Interest Income, Other									500,000
The 2022 MD Loan [Member] \| Department of Housing and Community Development [Member]
Debt Instrument, Face Amount				$ 3,000,000.0
Debt Instrument, Interest Rate, Stated Percentage				6.00%
Interest Expense, Debt, Total								23,000
Proceeds from Loans								$ 700,000
Debt Instrument, Monthly Interest-only Payments, Maximum Amount, First Eighteen Installments				$ 15,000
Debt Instrument, Monthly Principal and Interest Payment, for the Next Thirty Installments				33,306
Debt Issuance Costs, Gross				$ 31,000
The 2022 DHCD Loan [Member] \| Convertible Notes Payable [Member]
Debt Instrument, Interest Rate, Stated Percentage			6.00%					6.00%
The 2022 DHCD Loan [Member] \| Department of Housing and Community Development [Member]
Debt Instrument, Face Amount			$ 5,000,000.0					$ 5,000,000.0
Debt Instrument, Interest Rate, Stated Percentage			6.00%					6.00%
Debt Instrument, Convertible, Number of Equity Instruments			1,250,000
Interest Expense, Debt, Total								$ 7,200
Debt Issuance Costs, Gross			$ 100,000					$ 100,000
Debt Conversion, Conversion Price, Percent of 30-day Trailing Volume-weighted Average Sale Price of Common Stock			97.00%
Debt Instrument, Convertible, Conversion Price (in dollars per share) \| $ / shares			$ 4.00					$ 4.00
Debt Instrument, Convertible, Minimum Increment of Principal for Exercise			$ 1,000,000.0					$ 1,000,000.0
Coupon Interest Expense								7,500
Amortization of Debt Issuance Costs and Discounts, Total								$ 300
Debt Instrument, Interest Rate, Effective Percentage			5.91%					5.91%
The 2019 Cecil Loan [Member] \| Advance Cecil Inc. [Member]
Debt Instrument, Face Amount	$ 100,000
Debt Instrument, Interest Rate, Stated Percentage	8.00%
Debt Instrument, Convertible, Number of Equity Instruments	23,981
Interest Expense, Debt, Total								$ 8,000
Interest Income, Other									100,000
Paycheck Protection Program CARES Act [Member]
Debt Instrument, Face Amount										$ 600,000
The 2021 Avenue Loan [Member] \| Avenue [Member]
Debt Instrument, Face Amount						$ 30,000,000.0
Debt Instrument, Interest Rate, Stated Percentage						3.25%
Debt Instrument, Convertible, Number of Equity Instruments						482,703
Interest Expense, Debt, Total								$ 3,200,000	$ 1,500,000
Debt Issuance Costs, Gross						$ 500,000
Debt Instrument, Term (Month)						42 months
Debt Instrument, Interest Rate During Period								14.10%	9.85%
Debt Instrument, Interest Only Payments, Period (Month)						12 months
Debt Instrument, First Interest-only Period Extension (Month)						12 months
Additional Payment at Debt Maturity, Percentage of Principal						4.25%
Additional Payment at Debt Maturity						$ 900,000
Debt Instrument, Covenant, Cash and Certain Cash Equivalents, Minimum						5,000,000.0
Debt Instrument, Covenant, Minimum Proceeds from Issuance of Equity						30,000,000.0
Debt Instrument, Convertible, Maximum Conversion Amount						$ 5,000,000.0
Debt Instrument, Convertible, Conversion Price, Percentage of Warrant Exercise Price						120.00%
Convertible Notes Payable, Total			$ 5,000,000.0					$ 5,000,000.0
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total			$ 200,000					200,000	$ 400,000
Warrants and Rights Outstanding						$ 1,500,000
The 2021 Avenue Loan [Member] \| Avenue [Member] \| Convertible Notes Payable [Member]
Interest Expense, Debt, Total								800,000	400,000
Coupon Interest Expense								600,000	300,000
Amortization of Debt Issuance Costs and Discounts, Total								$ 200,000	$ 100,000
Debt Instrument, Interest Rate, Effective Percentage			19.69%					19.69%	15.46%
The 2021 Avenue Loan [Member] \| Avenue [Member] \| Prime Rate [Member]
Debt Instrument, Basis Spread on Variable Rate						6.60%
The 2021 Avenue Loan [Member] \| Avenue [Member] \| Notes Payable, Tranche 1 [Member]
Debt Instrument, Face Amount						$ 20,000,000.0
Debt Issuance Costs, Gross					$ 600,000		$ 600,000
Proceeds from Notes Payable, Total					$ 5,000,000.0	15,000,000.0
Amortization of Debt Issuance Costs							$ 47,000
The 2021 Avenue Loan [Member] \| Avenue [Member] \| Notes Payable, Tranche 2 [Member]
Debt Instrument, Unfunded Balance						$ 10,000,000.0

Note 9 - Note Payable and Convertible Notes Payable - Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Less notes payable, current portion, net of unamortized discount	$ (6,418)	$ 0
Total notes payable, net of current portion	9,483	14,484
Total convertible notes payable	9,770	4,598
Notes Payable [Member]
Notes payable	16,466	15,736
Accrued and unpaid interest	22	0
Less unamortized discount and debt issuance costs	(587)	(1,252)
Less notes payable, current portion, net of unamortized discount	(6,418)	0
Total notes payable, net of current portion	9,483	14,484
Convertible Notes Payable [Member]
Notes payable	10,000	5,000
Accrued and unpaid interest	7	0
Less unamortized discount and debt issuance costs	(237)	(402)
Total convertible notes payable	$ 9,770	4,598
The 2019 Cecil Loan [Member] \| Notes Payable [Member]
Interest Rate	8.00%
Notes payable	$ 130	122
The 2019 Maryland DHCD [Member] \| Notes Payable [Member]
Interest Rate	8.00%
Notes payable	$ 654	614
The 2022 Maryland DHCD [Member] \| Notes Payable [Member]
Interest Rate	6.00%
Notes payable	$ 682	0
Avenue [Member] \| Notes Payable [Member]
Interest Rate	14.10%
Notes payable	$ 15,000	15,000
Avenue [Member] \| Convertible Notes Payable [Member]
Interest Rate	14.10%
Notes payable	$ 5,000	5,000
The 2022 DHCD Loan [Member]
Notes payable		0
The 2022 DHCD Loan [Member] \| Notes Payable [Member]
Notes payable	4,957
Accrued and unpaid interest	$ 7
The 2022 DHCD Loan [Member] \| Convertible Notes Payable [Member]
Interest Rate	6.00%
Notes payable	$ 5,000	$ 0

Note 9 - Notes Payable and Convertible Notes Payable - Schedule of Future Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Notes Payable [Member]
Accrued and unpaid interest	$ 22	$ 0
Total	16,466	15,736
The 2021 Avenue Loan [Member] \| Notes Payable [Member]
2023	6,667
2024	13,333
2025	0
2026	0
2027	0
Thereafter	0
Subtotal of future principal payments	20,000
Accrued and unpaid interest	0
Less unamortized discount and debt issuance costs	(747)
Total	19,253
The 2022 MD Loan [Member]
Total		0
The 2022 MD Loan [Member] \| Notes Payable [Member]
2023	0
2024	0
2025	369
2026	313
2027	0
Thereafter	0
Subtotal of future principal payments	682
Accrued and unpaid interest	22
Less unamortized discount and debt issuance costs	(27)
Total	677
The 2022 DHCD Loan [Member]
Total		$ 0
The 2022 DHCD Loan [Member] \| Notes Payable [Member]
2023	0
2024	0
2025	0
2026	0
2027	0
Thereafter	5,000
Subtotal of future principal payments	5,000
Accrued and unpaid interest	7
Less unamortized discount and debt issuance costs	(50)
Total	$ 4,957

Note 10 - Common Stock Warrants (Details Textual) - $ / shares		12 Months Ended
	Dec. 30, 2020	Dec. 31, 2022	Dec. 31, 2021	May 31, 2021
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)		4,477,045
Class of Warrant or Right, Exercised During Period (in shares)		0
Warrants Originally Issued by Tottenham Acquisition I Limited [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)	2,407,500
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)	0.5
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.01
Class of Warrant or Right, Redemption, Threshold Stock Price Trigger (in dollars per share)	$ 16.50
Class of Warrant or Right, Redemption, Threshold Consecutive Trading Days (Day)	20 days
Class of Warrant or Right, Redemption, Threshold Trading Days (Day)	30 days
Class of Warrant or Right, Exercised During Period (in shares)		0	0
Chardan Unit Purchase Option [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)	24,583
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)	0.5
Class of Warrant or Right, Exercised During Period (in shares)		0	0
Warrants Originally Issued by Clene Nanomedicine [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)	1,929,111
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)	1
Class of Warrant or Right, Exercised During Period (in shares)		0	0
Warrants Issued with 2021 Avenue Loan [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				115,851
Class of Warrant or Right, Exercised During Period (in shares)		0	0

Note 10 - Common Stock Warrants - Outstanding Warrants (Details)

Dec. 31, 2022

$ / shares

Common Stock Warrant Exercisable on December 2020, One [Member]

4,477,045

2,407,500

^[1]

$ 11.50

Common Stock Warrant Exercisable on December 2020, Two [Member]

Dec. 31, 2025

24,583

^[2]

$ 11.50

Common Stock Warrant Exercisable on December 2020, Three [Member]

Dec. 31, 2025

1,929,111

^[3]

$ 1.97

Common Stock Warrant Exercisable on May 2021 [Member]

Apr. 30, 2023

115,851

^[4]

$ 8.63

May 31, 2026

[1]	Consists of 2,407,500 shares of Common Stock underlying warrants to purchase one-half (1/2) of one share of Common Stock, issued in connection with Tottenham’s initial public offering. We may redeem the outstanding warrants, in whole and not in part, at $0.01 per warrant if the last sales price of our Common Stock equals or exceeds $16.50 per share for any twenty trading days within a thirty-trading day period. As of December 31, 2022 and 2021, no warrants had been exercised.
[2]	Consists of 24,583 shares of Common Stock underlying warrants to purchase one-half (1/2) of one share of Common Stock, issued to Chardan Capital Markets, LLC (“Chardan”) upon exercise of their unit purchase option, which was issued in connection with Tottenham’s initial public offering. As of December 31, 2022 and 2021, no warrants had been exercised.
[3]	Consists of 1,929,111 shares of Common Stock underlying warrants to purchase one share of Common Stock, issued by Clene Nanomedicine as Series A preferred stock and senior equity Warrants in August 2013. As of December 31, 2022 and 2021, none of the warrants had been exercised.
[4]	Consists of 115,851 shares of Common Stock underlying the Avenue Warrant. As of December 31, 2022 and 2021, the warrant had not been exercised.

Note 11 - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2022	Dec. 31, 2021
Government Assistance, Amount		$ 3,079	$ 1,519
Grant Funding Related to VISIONARY-MS Phase 2 Clinical Trial [Member] \| National Multiple Sclerosis Society [Member]
Government Assistance, Amount	$ 300
Other Commitment, Repayment, Percentage of Grant Funding Upon First Commercial Product Sale	50.00%
Other Commitment, Repayment, Additional Percentage of Grant Funding, Tranche One	50.00%
Other Commitment, Repayment, Cumulative Sales, Tranche One	$ 10,000
Other Commitment, Repayment, Additional Percentage of Grant Funding, Tranche Two	150.00%
Other Commitment, Repayment, Cumulative Sales, Tranche Two	$ 50,000
Other Commitment, Repayment, Additional Percentage of Grant Funding, Tranche Three	200.00%
Other Commitment, Repayment, Cumulative Sales, Tranche Three	$ 100,000
Other Commitment, Repayment, Maximum Percentage of Grant Funding When All Milestones Achieved	450.00%
Other Commitment, Aggregate Repayment, Percentage of Grant Funding	300.00%
Other Commitment, Repayment, Percentage of Grant Funding Upon Closing	300.00%
Other Commitment, Repayment Amount Upon Closing	$ 1,000
Grant Funding Related to VISIONARY-MS Phase 2 Clinical Trial [Member] \| National Multiple Sclerosis Society [Member] \| Minimum [Member]
Other Commitment, Possible Loss, Percentage of Grant Funding	50.00%
Other Commitment, Possible Loss Between Minimum and Maximum Repayment Amounts	$ 200
Grant Funding Related to VISIONARY-MS Phase 2 Clinical Trial [Member] \| National Multiple Sclerosis Society [Member] \| Maximum [Member]
Other Commitment, Possible Loss, Percentage of Grant Funding	450.00%
Other Commitment, Possible Loss Between Minimum and Maximum Repayment Amounts	$ 1,500
Capital Addition Purchase Commitments [Member]
Long-Term Purchase Commitment, Amount		$ 1,600	$ 600

Note 12 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Effective Income Tax Rate Reconciliation, Percent, Total	0.00%	4.21%
Unrecognized Tax Benefits, Ending Balance	$ 0	$ 0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	0	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total	$ 0	$ 0
Open Tax Year	2014 2015 2016 2017 2018 2019 2020 2021 2022
Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	$ 3,800
Tax Credit Carryforward, Expiration Date	Dec. 31, 2034
Domestic Tax Authority [Member]
Operating Loss Carryforwards	$ 127,200
Operating Loss Carryforwards Not Subject to Expiration	93,700
Operating Loss Carryforwards Subject to Expiration	$ 33,500
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2034
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	$ 78,400
Operating Loss Carryforwards Not Subject to Expiration	65,500
Operating Loss Carryforwards Subject to Expiration	$ 12,900
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2032

Note 12 - Income Taxes - Components of Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
United States	$ (26,941)	$ (6,269)
Foreign	(2,977)	(3,899)
Net loss before income taxes	$ (29,918)	$ (10,168)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
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Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
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Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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Note 12 - Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Federal	$ 0	$ 0
State	0	0
Foreign	0	(146)
Total current tax expense	0	(146)
Federal	0	0
State	0	0
Foreign	0	(282)
Total deferred tax expense	0	(282)
Income tax expense	$ (0)	$ (428)

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Note 12 - Income Taxes - Reconciliation of Income Tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Income tax expense (benefit) at federal statutory rate	$ (6,282)	$ (2,135)
State income taxes (net of federal benefit)	(320)	(1,690)
Change in fair value of common stock warrant liability	(36)	(206)
Change in fair value of contingent earn-outs	(3,029)	(7,884)
Research and development tax credits	423	640
Stock compensation	(170)	(462)
Foreign rate differential	(261)	(157)
Other	67	625
Change in valuation allowance	10,454	12,121
Income tax expense	$ (0)	$ (428)

Note 12 - Income Taxes - Significant Components of Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Net operating loss carryforwards	$ 30,460	$ 26,898
Depreciation and amortization	1,131	1,478
Research and development tax credits	3,808	2,594
Lease liability	1,312	1,158
Right-of-use asset	(999)	(798)
Capitalized research and development expenses	4,712	0
Non-qualified stock options and restricted stock awards	3,849	2,815
Accrued compensation	396	74
Other	20	19
Total deferred tax assets (liabilities)	44,689	34,238
Less: valuation allowance	(44,689)	(34,238)
Net deferred tax assets (liabilities)	$ 0	$ 0

Note 13 - Benefit Plans (Details Textual) - USD ($)		12 Months Ended
Note 13 - Benefit Plans (Details Textual) - USD ($)	Dec. 30, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2014
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)		15,260,297	10,395,027
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate		0.00%	0.00%
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 18,200,000	$ 18,300,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		2 years 6 months 29 days	3 years 18 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate		0.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 1.49	$ 5.49
Restricted Stock [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 0	$ 0
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)		145,439
Restricted Stock [Member] \| Vests on Same Conditions as Milestone 1 of Contingent Earnout [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	454,781
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grant Date Fair Value	$ 4,300,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)			0
Restricted Stock [Member] \| Vests on Same Conditions as Milestone 2 of Contingent Earnout [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	341,090
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grant Date Fair Value	$ 3,500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)		0	0
The 2020 Stock Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	12,000,000
The 2020 Stock Plan [Member] \| Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent	100.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)	10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)		10,944,777
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)		1,055,223
The 2014 Stock Plan [Member] \| Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)				10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)				4 years
The 401(k) Plan [Member]
Defined Contribution Plan, Employer Matching Contribution, Percent of Match		100.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent		3.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount		$ 4,500
Defined Contribution Plan, Cost		$ 200,000	$ 200,000

Note 13 - Benefit Plans - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Total stock-based compensation	$ 8,513	$ 12,384
General and Administrative Expense [Member]
Total stock-based compensation	5,248	7,553
Research and Development Expense [Member]
Total stock-based compensation	3,265	4,831
Share-Based Payment Arrangement, Option [Member]
Total stock-based compensation	8,513	4,944
Restricted Stock Awards [Member]
Total stock-based compensation	$ 0	$ 7,440

Note 13 - Benefit Plans - Activity Related to Outstanding Stock Options (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Beginning balance outstanding, number of options (in shares)	10,395,027
Beginning balance outstanding, weighted average exercise price per share (in dollars per share)	$ 3.35
Outstanding, weighted average remaining term (Year)	7 years 3 months 10 days	6 years 3 months 25 days
Outstanding, intrinsic value	$ 2,348,000	$ 21,082,000
Granted, number of options (in shares)	6,371,537
Granted, weighted average exercise price per share (in dollars per share)	$ 1.96
Granted, weighted average remaining term (Year)	9 years 6 months 14 days
Exercised, number of options (in shares)	(1,219,360)
Exercised, weighted average exercise price per share (in dollars per share)	$ 0.25
Exercised, intrinsic value	$ 915,000
Forfeited, number of options (in shares)	(286,907)
Forfeited, weighted average exercise price per share (in dollars per share)	$ 5.46
Ending balance outstanding, number of options (in shares)	15,260,297	10,395,027
Ending balance outstanding, weighted average exercise price per share (in dollars per share)	$ 2.98	$ 3.35
Vested and exercisable, number of options (in shares)	7,097,942
Vested and exercisable, weighted average exercise price per share (in dollars per share)	$ 2.64
Vested and exercisable, weighted average remaining term (Year)	5 years 21 days
Vested and exercisable, intrinsic value	$ 2,348,000
Vested, exercisable and expected to vest, number of options (in shares)	15,260,297
Vested, exercisable and expected to vest, weighted average exercise price per share (in dollars per share)	$ 2.98
Vested, exercisable or expected to vest – December 31, 2022 (Year)	7 years 3 months 10 days
Vested, exercisable or expected to vest – December 31, 2022	$ 2,348

Note 13 - Benefit Plans - Assumptions of Stock Options (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Expected dividend yield	0.00%	0.00%
Expected term of options (in years) (Year)		6 years
Minimum [Member]
Expected stock price volatility	89.57%	87.40%
Risk-free interest rate	1.65%	0.72%
Expected term of options (in years) (Year)	5 years
Maximum [Member]
Expected stock price volatility	99.77%	91.51%
Risk-free interest rate	4.31%	1.34%
Expected term of options (in years) (Year)	6 years 11 months 23 days

Note 13 - Benefit Plans - Activity Related to Restricted Stock Awards (Details) - Restricted Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Unvested balance, number of restricted stock awards (in shares)	916,603
Unvested balance, weighted average grant date fair value (in dollars per share)	$ 9.84	$ 10.00
Converted to shares of Common Stock upon vesting, number of restricted stock awards (in shares)	(145,439)
Converted to shares of Common Stock upon vesting, weighted average grant date fair value (in dollars per share)		0
Forfeited, number of restricted stock awards (in shares)	(2,025)
Forfeited, weighted average grant date fair value (in dollars per share)		$ 9.84
Unvested balance, number of restricted stock awards (in shares)	769,139	916,603
Unvested balance, weighted average grant date fair value (in dollars per share)		$ 9.84

Note 14 - Fair Value (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Notes Payable, Current, Total	$ 6,418	$ 0
Notes Payable, Noncurrent, Total	9,483	14,484
Unrealized Gain (Loss) on Derivatives	$ 169	$ 983
Reverse Recapitalization [Member]
Business Combination, Earnout Shares Cancelled (in shares)		2,503,851
Reverse Recapitalization [Member] \| Contingent Earnout Shares [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)	5,842,334	750,000
Common Stock Warrant Liability [Member]
Unrealized Gain (Loss) on Derivatives	$ 200
The 2019 MD Loan [Member] \| Fair Value, Inputs, Level 3 [Member]
Long-Term Debt, Gross	700
The 2019 MD Loan [Member] \| Fair Value, Inputs, Level 1 [Member]
Long-Term Debt, Gross		$ 600
The 2019 Cecil Loan [Member] \| Fair Value, Inputs, Level 3 [Member]
Long-Term Debt, Gross	100
The 2019 Cecil Loan [Member] \| Fair Value, Inputs, Level 1 [Member]
Long-Term Debt, Gross		100
The 2021 Avenue Loan [Member] \| Fair Value, Inputs, Level 3 [Member]
Long-Term Debt, Gross	19,300	18,400
Notes Payable, Total	14,500	13,800
Notes Payable, Current, Total	6,400
Notes Payable, Noncurrent, Total	8,100
Convertible Notes Payable, Total	4,800	4,600
The 2022 MD Loan [Member]
Long-Term Debt, Gross		0
The 2022 MD Loan [Member] \| Fair Value, Inputs, Level 3 [Member]
Long-Term Debt, Gross	700
The 2022 DHCD Loan [Member]
Long-Term Debt, Gross		$ 0
The 2022 DHCD Loan [Member] \| Fair Value, Inputs, Level 3 [Member]
Long-Term Debt, Gross	$ 5,000

Note 14 - Fair Value - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Fair value	$ 4,983	$ 0
Clene Nanomedicine contingent earn-out liability	2,264
Initial Stockholders contingent earn-out liability	291
Commercial Paper [Member]
Fair value	3,482
Corporate Debt Securities [Member]
Fair value	1,501
Money Market Funds [Member]
Cash Equivalents	14,317
Fair Value, Recurring [Member]
Clene Nanomedicine contingent earn-out liability		18,100
Initial Stockholders contingent earn-out liability		2,317
Notes payable		736
Fair Value, Recurring [Member] \| Common Stock Warrant Liability [Member]
Derivative liability		474
Fair Value, Inputs, Level 1 [Member]
Clene Nanomedicine contingent earn-out liability	0
Initial Stockholders contingent earn-out liability	0
Fair Value, Inputs, Level 1 [Member] \| Commercial Paper [Member]
Fair value	0
Fair Value, Inputs, Level 1 [Member] \| Corporate Debt Securities [Member]
Fair value	0
Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member]
Cash Equivalents	14,317
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Clene Nanomedicine contingent earn-out liability		0
Initial Stockholders contingent earn-out liability		0
Notes payable		736
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Common Stock Warrant Liability [Member]
Derivative liability		0
Fair Value, Inputs, Level 2 [Member]
Clene Nanomedicine contingent earn-out liability	0
Initial Stockholders contingent earn-out liability	0
Fair Value, Inputs, Level 2 [Member] \| Commercial Paper [Member]
Fair value	3,482
Fair Value, Inputs, Level 2 [Member] \| Corporate Debt Securities [Member]
Fair value	1,501
Fair Value, Inputs, Level 2 [Member] \| Money Market Funds [Member]
Cash Equivalents	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Clene Nanomedicine contingent earn-out liability		0
Initial Stockholders contingent earn-out liability		0
Notes payable		0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Common Stock Warrant Liability [Member]
Derivative liability		0
Fair Value, Inputs, Level 3 [Member]
Clene Nanomedicine contingent earn-out liability	2,264
Initial Stockholders contingent earn-out liability	291
Fair Value, Inputs, Level 3 [Member] \| Commercial Paper [Member]
Fair value	0
Fair Value, Inputs, Level 3 [Member] \| Corporate Debt Securities [Member]
Fair value	0
Fair Value, Inputs, Level 3 [Member] \| Money Market Funds [Member]
Cash Equivalents	$ 0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Clene Nanomedicine contingent earn-out liability		18,100
Initial Stockholders contingent earn-out liability		2,317
Notes payable		0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Common Stock Warrant Liability [Member]
Derivative liability		$ 474

Note 14 - Fair Value - Changes in Fair Value (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Common Stock Warrant Liability [Member]
Balance	$ 474	$ 0
Change in fair value	0	(983)
Reclassification from liability to equity	(305)
Extinguishment of instrument	(169)
Balance – December 31, 2022	0	474
Initial fair value of instrument		1,457
Clene Nanomedicine Contingent Earn-out [Member]
Balance	18,100	52,053
Change in fair value	(15,836)	(33,953)
Reclassification from liability to equity	0
Extinguishment of instrument	0
Balance – December 31, 2022	2,264	18,100
Initial fair value of instrument		0
Initial Stockholders Contingent Earn-out [Member]
Balance	2,317	5,906
Change in fair value	(2,026)	(3,589)
Reclassification from liability to equity	0
Extinguishment of instrument	0
Balance – December 31, 2022	$ 291	2,317
Initial fair value of instrument		$ 0

Note 14 - Fair Value - Unobservable Inputs (Details)	12 Months Ended
Note 14 - Fair Value - Unobservable Inputs (Details)	Dec. 31, 2021	Dec. 31, 2022
The 2021 Avenue Loan [Member]
Probability of drawing Tranche 2	50.00%
Measurement Input, Price Volatility [Member] \| Common Stock Warrant Liability [Member]
Derivative, unobservable input	1.0500
Measurement Input, Price Volatility [Member] \| Contingent Earnout Shares [Member]
Derivative, unobservable input	1.0500
Measurement Input, Price Volatility [Member] \| Contingent Earnout Shares [Member] \| Minimum [Member]
Derivative, unobservable input		1.1500
Measurement Input, Risk Free Interest Rate [Member] \| Common Stock Warrant Liability [Member]
Derivative, unobservable input	0.0120
Measurement Input, Risk Free Interest Rate [Member] \| Contingent Earnout Shares [Member]
Derivative, unobservable input	0.0110
Measurement Input, Risk Free Interest Rate [Member] \| Contingent Earnout Shares [Member] \| Minimum [Member]
Derivative, unobservable input		0.0420
Measurement Input, Expected Dividend Rate [Member] \| Common Stock Warrant Liability [Member]
Derivative, unobservable input	0.0000
Measurement Input, Expected Dividend Rate [Member] \| Contingent Earnout Shares [Member]
Derivative, unobservable input	0.0000
Measurement Input, Expected Dividend Rate [Member] \| Contingent Earnout Shares [Member] \| Minimum [Member]
Derivative, unobservable input		0.0000
Measurement Input, Expected Term [Member] \| Common Stock Warrant Liability [Member] \| Minimum [Member]
Derivative, unobservable input	3.89
Measurement Input, Expected Term [Member] \| Common Stock Warrant Liability [Member] \| Maximum [Member]
Derivative, unobservable input	4.39
Measurement Input, Expected Term [Member] \| Contingent Earnout Shares [Member]
Derivative, unobservable input	4.00
Measurement Input, Expected Term [Member] \| Contingent Earnout Shares [Member] \| Minimum [Member]
Derivative, unobservable input		3.00

Note 15 - Common Stock (Details Textual) - USD ($)		1 Months Ended		6 Months Ended	12 Months Ended
Note 15 - Common Stock (Details Textual) - USD ($)	Apr. 14, 2022	Oct. 31, 2022	May 31, 2021	Dec. 20, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 29, 2020	Dec. 30, 2020
Common Stock, Shares Authorized (in shares)					150,000,000	150,000,000
Common Stock, Par or Stated Value Per Share (in dollars per share)					$ 0.0001	$ 0.0001		$ 0.0001
Preferred Stock, Shares Authorized (in shares)					1,000,000	1,000,000
Preferred Stock, Par or Stated Value Per Share (in dollars per share)					$ 0.0001	$ 0.0001
Common Stock, Shares, Issued (in shares)					74,759,591	62,312,097
Preferred Stock, Shares Issued (in shares)					0	0
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)					4,477,045
Proceeds from Warrant Exercises					$ 0	$ 11,000
Proceeds from Issuance of Common Stock					11,460,000	0
Payments of Stock Issuance Costs					$ (0)	$ 1,901,000
Class of Warrant or Right, Exercised During Period (in shares)					0
Common Stock, Shares, Outstanding, Ending Balance (in shares)					74,759,591	62,312,097
Preferred Stock, Shares Outstanding, Ending Balance (in shares)					0	0
PIPE Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)							0.5
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)							1,119,750
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)							$ 0.01
Class of Warrant or Right, Holding Period (Day)							180 days
Stock Issue During Period, Shares, Exercise of Warrants (in shares)				1,119,750
Proceeds from Warrant Exercises				$ 11,198
The 2020 PIPE [Member]
Stock Issued During Period, Shares, New Issues (in shares)							2,239,500
Shares Issued, Price Per Share (in dollars per share)							$ 10.00
Proceeds from Issuance or Sale of Equity, Total							$ 22,200,000
The 2021 PIPE [Member]
Stock Issued During Period, Shares, New Issues (in shares)			960,540
Shares Issued, Price Per Share (in dollars per share)			$ 9.63
Proceeds from Issuance or Sale of Equity, Total			$ 9,300,000
Offering Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)		10,723,926
Shares Issued, Price Per Share (in dollars per share)		$ 1.01
Proceeds from Issuance of Common Stock		$ 10,800,000
Payments of Stock Issuance Costs		$ 25,000
ATM Facility [Member]
Stock Issued During Period, Shares, New Issues (in shares)					358,769
Proceeds from Issuance of Common Stock					$ 800,000
Aggregate Offering Price	$ 50,000,000.0
Fixed Commission Rate Percentage	3.00%
Payments for Commissions					$ 23,000

Note 16 - Net Loss Per Share Attributable to Common Stockholders - Computation of Basic and Diluted Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Net loss	$ (29,918)	$ (9,740)
Weighted average common shares used to compute basic and diluted net loss per share (in shares)	65,204,663	61,558,455
Net loss per share – basic and diluted (in dollars per share)	$ (0.46)	$ (0.16)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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Note 16 - Net Loss Per Share Attributable to Common Stockholders - Antidilutive Securities Excluded from Computation (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Antidilutive securities (in shares)	28,831,518	22,863,712
Convertible Notes Payable [Member]
Antidilutive securities (in shares)	1,732,703	482,703
Common Stock Warrants [Member]
Antidilutive securities (in shares)	4,477,045	4,477,045
Share-Based Payment Arrangement, Option [Member]
Antidilutive securities (in shares)	15,260,297	10,395,027
Restricted Stock [Member]
Antidilutive securities (in shares)	769,139	916,603
Contingent Earnout Shares [Member]
Antidilutive securities (in shares)	6,592,334	6,592,334

Note 17 - Related Party Transactions (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		12 Months Ended
	Oct. 31, 2022	Aug. 31, 2018	Dec. 31, 2022	Dec. 31, 2021
Proceeds from Issuance of Common Stock			$ 11,460	$ 0
Offering Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)	10,723,926
Shares Issued, Price Per Share (in dollars per share)	$ 1.01
Proceeds from Issuance of Common Stock	$ 10,800
Offering Agreement [Member] \| Directors of Clene Inc and Clene Nanomedicine [Member]
Stock Issued During Period, Shares, New Issues (in shares)	6,287,129
Shares Issued, Price Per Share (in dollars per share)	$ 1.01
Proceeds from Issuance of Common Stock	$ 6,400
4Life [Member] \| Supply Agreement [Member]
Related Party Transaction, Exclusive License Term (Year)		5 years
Related Party Transaction, Royalty Fee Rate for Revenues		3.00%

Note 17 - Related Party Transactions - Revenue From 4Life Agreement (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenue	$ 460	$ 632
Product [Member]
Revenue	316	479
Royalty [Member]
Revenue	$ 144	$ 153

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Note 18 - Geographic and Segment Information - Long-lived Assets by Location (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Long-lived assets	$ 10,638	$ 5,172
UNITED STATES
Long-lived assets	10,638	5,142
AUSTRALIA
Long-lived assets	$ 0	$ 30

Note 18 - Geographic and Segment Information - Profit and Loss Information by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenue from external customers	$ 473	$ 723
Depreciation expense	1,019	955
Stock compensation expense	8,513	12,384
Segment loss from operations	(48,409)	(49,978)
Operating Segments [Member] \| Drugs Segment [Member]
Revenue from external customers	0	0
Depreciation expense	974	910
Stock compensation expense	8,513	12,384
Segment loss from operations	(48,769)	(50,183)
Operating Segments [Member] \| Supplements Segment [Member]
Revenue from external customers	473	723
Depreciation expense	45	45
Stock compensation expense	0	0
Segment loss from operations	$ 360	$ 205

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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Note 18 - Geographic and Segment Information - Reconciliation of the Reportable Segments' Loss From Operations to Consolidated (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Segment loss from operations	$ (48,409)	$ (49,978)
Total other income (expense), net	18,491	39,810
Net loss before income taxes	$ (29,918)	$ (10,168)

Note 18 - Geographic and Segment Information - Assets by Reportable Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Total assets	$ 44,493	$ 63,063
Operating Segments [Member] \| Drugs Segment [Member]
Total assets	20,476	12,052
Operating Segments [Member] \| Supplements Segment [Member]
Total assets	386	337
Corporate, Non-Segment [Member]
Total assets	$ 23,631	$ 50,674

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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