0001437749-23-014242 | 10-Q | XBRL Viewer

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

4,477,045

2,407,500

^[1]

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

$ 11.50

24,583

^[2]

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

$ 11.50

1,929,111

^[3]

Common Stock Warrant Exercisable on May 2021 [Member]

$ 1.97

115,851

^[4]

$ 8.63

[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 March 31, 2023 and December 31, 2022, 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 the financial advisor and lead underwriter of Tottenham’s initial public offering upon their exercise of a unit purchase option in July 2021. As of March 31, 2023 and December 31, 2022, 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 warrants and senior equity warrants in August 2013. As of March 31, 2023 and December 31, 2022, no warrants had been exercised. As of April 2023, the warrants expired.
[4]	Consists of 115,851 shares of Common Stock underlying the Avenue Warrant. As of March 31, 2023 and December 31, 2022, the warrant had not been exercised.

Condensed Consolidated Statements of Stockholders' Equity (Deficit) (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balances (in shares) at Dec. 31, 2021	62,312,097
Balances at Dec. 31, 2021	$ 6	$ 175,659	$ (163,301)	$ 233	$ 12,597
Stock-based compensation expense	0	2,202	0	0	2,202
Unrealized gain on available-for-sale securities	0	0	0	(50)	(50)
Foreign currency translation adjustments	0	0	0	50	50
Net loss	$ 0	0	(13,354)	0	(13,354)
Balances (in shares) at Mar. 31, 2022	63,246,545
Balances at Mar. 31, 2022	$ 6	178,433	(176,655)	233	2,017
Reclassification of common stock warrant liability to permanent equity	$ 0	305	0	0	305
Exercise of stock options (in shares)	934,448
Exercise of stock options	$ 0	267	0	0	267
Balances (in shares) at Dec. 31, 2022	74,759,591
Balances at Dec. 31, 2022	$ 7	196,246	(193,219)	203	3,237
Issuance of common stock (in shares)	3,227,758
Issuance of common stock	$ 1	4,664	0	0	4,665
Stock-based compensation expense	0	2,223	0	0	2,223
Unrealized gain on available-for-sale securities	0	0	0	14	14
Foreign currency translation adjustments	0	0	0	4	4
Net loss	$ 0	0	(11,770)	0	(11,770)
Balances (in shares) at Mar. 31, 2023	77,987,349
Balances at Mar. 31, 2023	$ 8	$ 203,133	$ (204,989)	$ 221	(1,627)
Reclassification of common stock warrant liability to permanent equity					$ 0

Note 5 - Property and Equipment, Net - Schedule of Depreciation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Depreciation	$ 402	$ 195
General and Administrative Expense [Member]
Depreciation	67	29
Research and Development Expense [Member]
Depreciation	$ 335	$ 166

Note 16 - Segment Information

3 Months Ended

Mar. 31, 2023

Segment Reporting Disclosure [Text Block]

Note 16. 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 three months ended March 31, 2023 and 2022 was as follows:

	*Three Months Ended March 31,*
(in thousands)	*2023*			*2022*
Drugs:
Revenue from external customers	$	—		$	—
Loss from operations		(10,798	)		(13,343	)
Supplements:
Revenue from external customers	$	107		$	30
Income from operations		66			7
Consolidated:
Revenue from external customers	$	107		$	30
Loss from operations		(10,732	)		(13,336	)

A reconciliation of the total of the reportable segments’ loss from operations to consolidated net loss before income taxes for the three months ended March 31, 2023 and 2022 was as follows:

	*Three Months Ended March 31,*
(in thousands)	*2023*			*2022*
Segment loss from operations	$	(10,732	)	$	(13,336	)
Total other income (expense), net		(1,038	)		(18	)
Net loss before income taxes	$	(11,770	)	$	(13,354	)

Segment assets exclude corporate assets, such as cash, restricted cash, and corporate facilities. Total assets by reportable segment as of March 31, 2023 and December 31, 2022, were as follows:

	*March 31,*		*December 31,*
(in thousands)	*2023*		*2022*
Total assets:
Drugs	$	20,875	$	20,476
Supplements		272		386
Corporate		18,741		23,631
Consolidated	$	39,888	$	44,493

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 17 - Subsequent Events

3 Months Ended

Mar. 31, 2023

Subsequent Events [Text Block]

Note 17. Subsequent Events

Common Stock Purchase Agreement

Subsequent to March 31, 2023, we sold 400,000 shares of Common Stock under the Purchase Agreement with Lincoln Park and generated proceeds of $0.4 million, and we issued 2,893 Additional Commitment Shares pursuant to the Purchase Agreement. The issuance and sale of Common Stock under the Purchase Agreement 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.

Note 10 - Income Taxes (Tables)

3 Months Ended

Mar. 31, 2023

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

	*Three Months Ended March 31,*
(in thousands)	*2023*			*2022*
United States	$	(11,546	)	$	(12,957	)
Foreign		(224	)		(397	)
Net loss before income taxes	$	(11,770	)	$	(13,354	)

Note 12 - Fair Value - Unobservable Inputs (Details) - Contingent Earnout Shares [Member]	Mar. 31, 2023	Dec. 31, 2022
Measurement Input, Price Volatility [Member]
Derivative, unobservable input		1.1500
Measurement Input, Price Volatility [Member] \| Minimum [Member]
Derivative, unobservable input	1.1500
Measurement Input, Risk Free Interest Rate [Member]
Derivative, unobservable input		0.0420
Measurement Input, Risk Free Interest Rate [Member] \| Minimum [Member]
Derivative, unobservable input	0.0390
Measurement Input, Expected Dividend Rate [Member]
Derivative, unobservable input		0.0000
Measurement Input, Expected Dividend Rate [Member] \| Minimum [Member]
Derivative, unobservable input	0.0000
Measurement Input, Expected Term [Member]
Derivative, unobservable input		3.00
Measurement Input, Expected Term [Member] \| Minimum [Member]
Derivative, unobservable input	2.75

Note 16 - Segment Information - Profit and Loss Information by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenue from external customers	$ 107	$ 30
Segment loss from operations	(10,732)	(13,336)
Operating Segments [Member] \| Drugs Segment [Member]
Revenue from external customers	0	0
Segment loss from operations	(10,798)	(13,343)
Operating Segments [Member] \| Supplements Segment [Member]
Revenue from external customers	107	30
Segment loss from operations	$ 66	$ 7

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 14 - Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2023

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

	*Three Months Ended March 31,*
(in thousands, except share and per share data)	*2023*			*2022*
Numerator:
Net loss attributable to common stockholders	$	(11,770	)	$	(13,354	)
Denominator:
Weighted average common shares outstanding		76,049,665			62,852,863
Net loss per share attributable to common stockholders – basic and diluted	$	(0.15	)	$	(0.21	)

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

	*Three Months Ended March 31,*
	*2023*		*2022*
Convertible notes payable (see Note 8)		1,732,703		482,703
Common stock warrants (see Note 13)		4,477,045		4,477,045
Options to purchase common stock (see Note 11)		16,205,404		11,944,789
Unvested restricted stock awards (see Note 11)		812,170		914,876
Contingent earn-out shares (see Note 2)		6,592,334		6,592,334
Total		29,819,656		24,411,747

Note 13 - Capital Stock (Tables)

3 Months Ended

Mar. 31, 2023

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

Date Exercisable	Number of Shares Issuable			Exercise Price		Expiration
December 2020		2,407,500	(1)	$	11.50	December 2025
December 2020		24,583	(2)	$	11.50	December 2025
December 2020		1,929,111	(3)	$	1.97	April 2023
May 2021		115,851	(4)	$	8.63	May 2026
Total		4,477,045

Note 4 - Prepaid Expenses and Other Current Assets (Tables)

3 Months Ended

Mar. 31, 2023

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

	*March 31,*		*December 31,*
(in thousands)	*2023*		*2022*
Research and development tax credits receivable	$	3,051	$	2,777
Metals to be used in research and development		2,216		2,290
Other		962		581
Total prepaid expenses and other current assets	$	6,229	$	5,648

Note 7 - Leases (Details Textual) $ in Thousands	1 Months Ended			3 Months Ended		12 Months Ended
Note 7 - Leases (Details Textual) $ in Thousands	Sep. 30, 2022	Feb. 28, 2022	Sep. 30, 2021	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Number of Real Estate Leases				3
Gain (Loss) on Termination of Lease				$ (0)	$ 420
Operating Lease, Weighted Average Discount Rate, Percent				9.60%		9.60%
Operating Lease, Weighted Average Remaining Lease Term (Year)				7 years 1 month 6 days		7 years 3 months 18 days
Finance Lease, Weighted Average Discount Rate, Percent				10.80%		10.20%
Finance Lease, Weighted Average Remaining Lease Term (Year)				1 year		1 year 2 months 12 days
Lease for Laboratory Space [Member]
Lessee, Operating Lease, Term of Contract (Year)		7 years	10 years
Lessee, Operating Lease, Option To Extend Period (Year)	5 years	10 years	10 years
Gain (Loss) on Termination of Lease						$ 400
Lessee, Operating Lease, Renewal Term (Year)	7 years

Note 8 - Notes Payable and Convertible Notes Payable (Tables)

3 Months Ended

Mar. 31, 2023

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

	*Stated*			*March 31,*			*December 31,*
(in thousands, except interest rates)	*Interest Rate*			*2023*			*2022*
Notes payable
Advance Cecil, Inc. (commenced April 2019)		8.00	%	$	132		$	130
Maryland DHCD (commenced February 2019)		8.00	%		664			654
Maryland DHCD (commenced May 2022)		6.00	%		1,032			682
Avenue Venture Opportunities Fund, L.P. (commenced May 2021)		14.60	%		15,000			15,000
					16,828			16,466
Accrued and unpaid interest					35			22
Less unamortized discount and debt issuance costs					(399	)		(587	)
Less notes payable, current portion, net of unamortized discount and debt issuance costs					(9,751	)		(6,418	)
Total notes payable, net of current portion				$	6,713		$	9,483

Convertible notes payable
Avenue Venture Opportunities Fund, L.P. (commenced May 2021)		14.60	%	$	5,000		$	5,000
Maryland DHCD (commenced December 2022)		6.00	%		5,000			5,000
					10,000			10,000
Accrued and unpaid interest					83			7
Less unamortized discount and debt issuance costs					(176	)		(237	)
Total convertible notes payable				$	9,907		$	9,770

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

(in thousands)	2019 MD Loan		2019 Cecil Loan		2021 Avenue Loan			2022 MD Loan			2022 DHCD Loan
2023 (remainder)	$	—	$	—	$	6,667		$	—		$	—
2024		—		—		13,333			—			—
2025		—		—		—			347			—
2026		—		—		—			369			—
2027		—		—		—			317			—
2028		—		—		—			—			5,000
Thereafter		664		132		—			—			—
Subtotal of future principal payments		664		132		20,000			1,033			5,000
Accrued and unpaid interest		—		—		—			35			83
Less unamortized discount and debt issuance costs		—		—		(497	)		(26	)		(52	)
Total	$	664	$	132	$	19,503		$	1,042		$	5,031

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 4 - Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Research and development tax credits receivable	$ 3,051	$ 2,777
Metals to be used in research and development	2,216	2,290
Other	962	581
Total prepaid expenses and other current assets	$ 6,229	$ 5,648

Note 1 - Nature of the Business (Details Textual) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Apr. 01, 2023	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 30, 2020
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.0001		$ 0.0001	$ 0.0001
Operating Income (Loss)		$ (10,732)	$ (13,336)
Retained Earnings (Accumulated Deficit)		(204,989)		$ (193,219)
Cash, Cash Equivalents, and Short-Term Investments		18,400		$ 23,300
Net Cash Provided by (Used in) Operating Activities		(9,218)	(13,084)
Minimum Cash Balance For Loan Covenant		5,000
Proceeds from Issuance of Common Stock		$ 4,266	$ 0
Subsequent Event [Member]
Proceeds from Issuance of Common Stock	$ 400

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Note 13 - Capital Stock

3 Months Ended

Mar. 31, 2023

Equity [Text Block]

Note 13. Capital Stock

As of March 31, 2023 and December 31, 2022, our amended and restated certificate of incorporation (the “Certificate”) 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. As of March 31, 2023 and December 31, 2022, we had 77,987,349 and 74,759,591 shares of Common Stock issued and outstanding, respectively, and no shares of preferred stock issued or outstanding. On May 9, 2023, our stockholders approved an amendment to the Certificate which increased the number of authorized shares of Common Stock to 300,000,000 shares.

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.

Common Stock Warrants

As of March 31, 2023 and December 31, 2022, outstanding warrants to purchase shares of Common Stock were as follows:

Date Exercisable	Number of Shares Issuable			Exercise Price		Expiration
December 2020		2,407,500	(1)	$	11.50	December 2025
December 2020		24,583	(2)	$	11.50	December 2025
December 2020		1,929,111	(3)	$	1.97	April 2023
May 2021		115,851	(4)	$	8.63	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 March 31, 2023 and December 31, 2022, 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 the financial advisor and lead underwriter of Tottenham’s initial public offering upon their exercise of a unit purchase option in July 2021. As of March 31, 2023 and December 31, 2022, 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 warrants and senior equity warrants in August 2013. As of March 31, 2023 and December 31, 2022, no warrants had been exercised. As of April 2023, the warrants expired.

(4)	Consists of 115,851 shares of Common Stock underlying the Avenue Warrant. As of March 31, 2023 and December 31, 2022, the warrant had not been exercised.

Public Offerings

In October 2022, we sold 10,723,926 shares of Common Stock at a sale price of $1.01 per share to certain existing stockholders, including affiliates of our directors. The aggregate gross proceeds were $10.8 million and we paid expenses of $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.

Common Stock Sales Agreement

In April 2022, we entered into an Equity Distribution Agreement (the “ATM Agreement”) with Canaccord Genuity LLC and Oppenheimer & Co. Inc., as placement agents (the “Placement Agents”). In December 2022, we amended the ATM Agreement and removed Oppenheimer & Co. Inc. as a Placement Agent. In accordance with the terms of the ATM Agreement, 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 Agreement 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 Agreement, 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 Agreement at a fixed commission rate of 3.0% of the gross proceeds from each issuance and sale of Common Stock, if any. During the three months ended March 31, 2023, we sold 2,895,090 shares of Common Stock under the ATM Agreement, generated gross proceeds of $4.5 million, and paid commissions of $0.1 million.

Common Stock Purchase Agreement

On March 3, 2023, we entered into a purchase agreement (the “Purchase Agreement”) with Lincoln Park Capital Fund, LLC (“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 evaluated the Purchase Agreement under ASC 815-40 “Derivatives and Hedging—Contracts on an Entity's Own Equity” as it represents the right to require Lincoln Park to purchase shares of Common Stock in the future, similar to a put option. We concluded it represents a freestanding derivative instrument that does not qualify for equity classification and therefore requires fair value accounting. We analyzed the terms of the contract and concluded the derivative instrument has no value as of March 31, 2023.

On the date of the Purchase Agreement, 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. We recorded the fair value of the Initial Commitment Shares on the date of issuance in other income (expense), net. We may further 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 61st 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. During the three months ended March 31, 2023, we did not make any sales under the Purchase Agreement.

The entire disclosure for equity.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Note 11 - Benefit Plans - Activity Related to Outstanding Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Beginning balance outstanding, number of options (in shares)	15,260,297
Beginning balance outstanding, weighted average exercise price per share (in dollars per share)	$ 2.98
Outstanding, weighted average remaining term (Year)	7 years 2 months 19 days	7 years 3 months 10 days
Outstanding, intrinsic value	$ 2,923	$ 2,348
Granted, number of options (in shares)	1,077,432
Granted, weighted average exercise price per share (in dollars per share)	$ 1.30
Granted, weighted average remaining term (Year)	9 years 10 months 20 days
Forfeited, number of options (in shares)	(132,325)
Forfeited, weighted average exercise price per share (in dollars per share)	$ 5.83
Ending balance outstanding, number of options (in shares)	16,205,404	15,260,297
Ending balance outstanding, weighted average exercise price per share (in dollars per share)	$ 2.85	$ 2.98
Vested and exercisable, number of options (in shares)	8,085,513
Vested and exercisable, weighted average exercise price per share (in dollars per share)	$ 2.76
Vested and exercisable, weighted average remaining term (Year)	5 years 3 months 14 days
Vested and exercisable, intrinsic value	$ 2,855
Vested, exercisable and expected to vest, number of options (in shares)	16,205,404
Vested, exercisable and expected to vest, weighted average exercise price per share (in dollars per share)	$ 2.85
Vested, exercisable or expected to vest – March 31, 2023 (Year)	7 years 2 months 19 days
Vested, exercisable or expected to vest – March 31, 2023	$ 2,923

Condensed Consolidated Balance Sheets (Current period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 18,442	$ 18,332
Marketable securities	0	4,983
Accounts receivable	63	189
Inventory	88	43
Prepaid expenses and other current assets	6,229	5,648
Total current assets	24,822	29,195
Restricted cash	58	58
Operating lease right-of-use assets	4,494	4,602
Property and equipment, net	10,514	10,638
TOTAL ASSETS	39,888	44,493
Current liabilities:
Accounts payable	608	3,014
Accrued liabilities	5,933	3,863
Operating lease obligations, current portion	508	488
Finance lease obligations, current portion	76	74
Notes payable, current portion	9,751	6,418
Total current liabilities	16,876	13,857
Operating lease obligations, net of current portion	5,399	5,557
Finance lease obligations, net of current portion	3	34
Notes payable, net of current portion	6,713	9,483
Convertible notes payable	9,907	9,770
Clene Nanomedicine contingent earn-out liability	2,319	2,264
Initial Stockholders contingent earn-out liability	298	291
TOTAL LIABILITIES	41,515	41,256
Commitments and contingencies (Note 9)
Stockholders’ equity (deficit):
Common stock, $0.0001 par value: 150,000,000 shares authorized; 77,987,349 and 74,759,591 shares issued and outstanding at March 31, 2023 and December 31, 2022, respectively	8	7
Additional paid-in capital	203,133	196,246
Accumulated deficit	(204,989)	(193,219)
Accumulated other comprehensive income	221	203
TOTAL STOCKHOLDERS’ EQUITY (DEFICIT)	(1,627)	3,237
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)	$ 39,888	$ 44,493

Note 6 - Accrued Liabilities (Tables)

3 Months Ended

Mar. 31, 2023

Schedule of Accrued Liabilities [Table Text Block]

	*March 31,*		*December 31,*
(in thousands)	*2023*		*2022*
Accrued compensation and benefits	$	2,638	$	2,007
Accrued CRO and clinical fees		2,752		1,297
Other		543		559
Total accrued liabilities	$	5,933	$	3,863

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (11,770)	$ (13,354)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	402	195
Non-cash lease expense	108	52
Commitment share expense	399	(0)
Change in fair value of common stock warrant liability	(0)	18
Change in fair value of Clene Nanomedicine contingent earn-out liability	55	57
Change in fair value of Initial Stockholders contingent earn-out liability	7	12
Stock-based compensation expense	2,223	2,202
Gain on termination of lease	0	(420)
Accretion of debt discount	250	227
Non-cash interest expense	82	45
Changes in operating assets and liabilities:
Accounts receivable	126	49
Inventory	(45)	3
Prepaid expenses and other current assets	(581)	(1,691)
Accounts payable	(2,406)	1,389
Accrued liabilities	2,070	(2,069)
Operating lease obligations	(138)	201
Net cash used in operating activities	(9,218)	(13,084)
Cash flows from investing activities:
Purchases of marketable securities	0	(23,586)
Proceeds from maturities of marketable securities	5,000	0
Purchases of property and equipment	(278)	(936)
Net cash provided by (used in) investing activities	4,722	(24,522)
Cash flows from financing activities:
Proceeds from exercise of stock options	0	267
Proceeds from issuance of common stock, net of offering costs	4,266	0
Payments of finance lease obligations	(28)	(32)
Proceeds from the issuance of notes payable	350	0
Net cash provided by financing activities	4,588	235
Effect of foreign exchange rate changes on cash and restricted cash	18	13
Net increase (decrease) in cash, cash equivalents and restricted cash	110	(37,358)
Cash, cash equivalents and restricted cash – beginning of period	18,390	50,346	$ 50,346
Cash, cash equivalents and restricted cash – end of period	18,500	12,988	$ 18,390
Reconciliation of cash, cash equivalents and restricted cash to the consolidated balance sheets
Cash and cash equivalents	18,442	12,930
Restricted cash	58	58
Cash, cash equivalents and restricted cash	18,500	12,988
Supplemental disclosure of non-cash investing and financing activities:
Lease liability arising from obtaining right-of-use assets, leasehold improvements, and lease incentives	0	2,343
Lease liability settled through termination of lease	0	602
Reclassification of common stock warrant liability to permanent equity	0	305
Supplemental cash flow information:
Cash paid for interest expense	$ 982	$ 493

Note 12 - Fair Value (Details Textual) $ in Millions	12 Months Ended
Note 12 - Fair Value (Details Textual) $ in Millions	Dec. 31, 2022 USD ($)
Common Stock Warrant Liability [Member]
Unrealized Gain (Loss) on Derivatives	$ 0.2

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References + Details

Note 4 - Prepaid Expenses and Other Current Assets

3 Months Ended

Mar. 31, 2023

Prepaid Expenses and Other Current Assets [Text Block]

Note 4. Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets as of March 31, 2023 and December 31, 2022 were as follows:

	*March 31,*		*December 31,*
(in thousands)	*2023*		*2022*
Research and development tax credits receivable	$	3,051	$	2,777
Metals to be used in research and development		2,216		2,290
Other		962		581
Total prepaid expenses and other current assets	$	6,229	$	5,648

Note 14 - Net Loss Per Share - Computation of Basic and Diluted Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Net loss	$ (11,770)	$ (13,354)
Weighted average common shares used to compute basic and diluted net loss per share (in shares)	76,049,665	62,852,863
Net loss per share – basic and diluted (in dollars per share)	$ (0.15)	$ (0.21)

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Note 11 - Benefit Plans - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Total stock-based compensation expense	$ 2,223	$ 2,202
Share-Based Payment Arrangement, Option [Member]
Total stock-based compensation expense	2,222	2,202
Restricted Stock Awards [Member]
Total stock-based compensation expense	1	0
General and Administrative Expense [Member]
Total stock-based compensation expense	1,250	1,458
Research and Development Expense [Member]
Total stock-based compensation expense	$ 973	$ 744

Note 10 - Income Taxes - Components of Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
United States	$ (11,546)	$ (12,957)
Foreign	(224)	(397)
Net loss before income taxes	$ (11,770)	$ (13,354)

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.

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Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($)	Dec. 30, 2020	Mar. 31, 2023	Dec. 31, 2022
Inventory, Raw Materials, Gross		$ 100,000	$ 29,000
Inventory, Finished Goods, Gross		$ 19,000	$ 14,000
Reverse Recapitalization [Member] \| Clene Nanomedicine Contingent Earn-out [Member]
Business Combination, Contingent Earnout Shares, Milestone One (in shares)	3,338,483
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 Shares, Milestone Two (in shares)	2,503,851
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
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
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 11 - Benefit Plans - Assumptions of Stock Options (Details)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Expected dividend yield	0.00%	0.00%
Minimum [Member]
Expected stock price volatility	96.22%	89.57%
Risk-free interest rate	3.38%	1.65%
Expected term of options (in years) (Year)	5 years	5 years
Maximum [Member]
Expected stock price volatility	103.24%	93.07%
Risk-free interest rate	3.98%	2.02%
Expected term of options (in years) (Year)	6 years 29 days	6 years 11 months 23 days

Document And Entity Information - shares	3 Months Ended
Document And Entity Information - shares	Mar. 31, 2023	May 09, 2023
Document Information [Line Items]
Entity Central Index Key	0001822791
Entity Registrant Name	Clene Inc.
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2023
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2023
Document Transition Report	false
Entity File Number	01-39834
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	85-2828339
Entity Address, Address Line One	6550 South Millrock Drive, Suite G50
Entity Address, City or Town	Salt Lake City
Entity Address, State or Province	UT
Entity Address, Postal Zip Code	84121
City Area Code	801
Local Phone Number	676 9695
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		78,393,865
Warrant [Member]
Document Information [Line Items]
Title of 12(b) Security	Warrants, to acquire one-half of one share of Common Stock for $11.50 per share
Trading Symbol	CLNNW
Security Exchange Name	NASDAQ
Common Stock [Member]
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.0001 par value
Trading Symbol	CLNN
Security Exchange Name	NASDAQ

Note 7 - Leases - Maturity Analysis of Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
2022 (remainder), finance leases	$ 65
2023 (remainder), operating leases	767
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
2028, finance leases	0
2028, operating leases	1,092
Thereafter, finance leases	0
Thereafter, operating leases	1,694
Total undiscounted cash flows, finance leases	92
Total undiscounted cash flows, operating leases	8,286
Less amount representing interest/discounting, finance leases	(13)
Less amount representing interest/discounting, operating leases	(2,379)
Present value of future lease payments, finance leases	79
Present value of future lease payments, operating leases	5,907
Less lease obligations, current portion, finance leases	76	$ 74
Less lease obligations, current portion, operating leases	508	488
Lease obligations, long term portion, finance leases	3	34
Lease obligations, long term portion, operating leases	$ 5,399	$ 5,557

Note 10 - Income Taxes

3 Months Ended

Mar. 31, 2023

Income Tax Disclosure [Text Block]

Note 10. Income Taxes

The components of loss before income taxes for the three months ended March 31, 2023 and 2022 were as follows:

	*Three Months Ended March 31,*
(in thousands)	*2023*			*2022*
United States	$	(11,546	)	$	(12,957	)
Foreign		(224	)		(397	)
Net loss before income taxes	$	(11,770	)	$	(13,354	)

We are subject to taxation in the U.S., Australia, Netherlands, and various state jurisdictions. Our tax returns from 2016 to present are subject to examination by the U.S. and state authorities due to the carry forward of unutilized net operating losses and research and development credits. There are currently no pending examinations. We compute our quarterly income tax provision by using a forecasted annual effective tax rate and adjust for any discrete items arising during the quarter. The primary difference between the effective tax rate and the federal statutory tax rate relates to the full valuation allowance on our net operating losses and other deferred tax assets.

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.

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Note 16 - Segment Information - Assets by Reportable Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Total assets	$ 39,888	$ 44,493
Operating Segments [Member] \| Drugs Segment [Member]
Total assets	20,875	20,476
Operating Segments [Member] \| Supplements Segment [Member]
Total assets	272	386
Corporate, Non-Segment [Member]
Total assets	$ 18,741	$ 23,631

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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Note 11 - Benefit Plans

3 Months Ended

Mar. 31, 2023

Share-Based Payment Arrangement [Text Block]

Note 11. Benefit Plans

401(k) Plan

Our 401(k) plan is a deferred salary arrangement under Section 401(k) of the Internal Revenue Code. 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 $0.1 million and $0.1 million for the three months ended March 31, 2023 and 2022, respectively.

Stock Compensation Plans

The Clene Nanomedicine, Inc. 2014 Stock Plan (“the 2014 Stock Plan”) was adopted in July 2014. Effective as of the closing of the Reverse Recapitalization, no additional awards may be granted under the 2014 Stock Plan. As of March 31, 2023, 5,367,340 stock options remained outstanding under the 2014 Stock Plan.

The Clene Inc. 2020 Stock Plan (the “2020 Stock Plan”) was adopted in December 2020 and 12,000,000 shares of Common Stock were reserved for issuance thereunder. As of March 31, 2023, a total of 11,933,488 stock options and other stock awards had been granted under the 2020 Stock Plan, and 66,512 shares remained available for future grant. On May 9, 2023, the 2020 Stock Plan was amended and the shares reserved for issuance thereunder was increased by 6,400,000 shares.

Stock-Based Compensation Expense

Stock-based compensation expense recorded in research and development expense and general and administrative expense for the three months ended March 31, 2023 and 2022 was as follows:

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
General and administrative	$	1,250	$	1,458
Research and development		973		744
Total stock-based compensation expense	$	2,223	$	2,202

Stock-based compensation expense by award type for the three months ended March 31, 2023 and 2022 was as follows:

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
Stock options	$	2,222	$	2,202
Stock awards		1		—
Total stock-based compensation expense	$	2,223	$	2,202

Stock Options

Outstanding stock options and related activity for the three months ended March 31, 2023 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, 2022		15,260,297		$	2.98		7.28	$	2,348
Granted		1,077,432			1.30		9.89		—
Forfeited		(132,325	)		5.83		—		—
Outstanding – March 31, 2023		16,205,404		$	2.85		7.22	$	2,923
Vested and exercisable – March 31, 2023		8,085,513		$	2.76		5.29	$	2,855
Vested, exercisable or expected to vest – March 31, 2023		16,205,404		$	2.85		7.22	$	2,923

As of March 31, 2023 and December 31, 2022, we had approximately $16.8 million and $18.2 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 2.36 years and 2.58 years, respectively.

The weighted-average grant-date fair value of stock options granted during the three months ended March 31, 2023 and 2022 was $0.99 and $2.25, respectively. The assumptions used to calculate the fair value of stock options granted during the three months ended March 31, 2023 and 2022 were as follows:

	*Three Months Ended March 31,*
	*2023*			*2022*
Expected stock price volatility		96.22% – 103.24%			89.57% – 93.07%
Risk-free interest rate		3.38% – 3.98%			1.65% – 2.02%
Expected dividend yield		0.00	%		0.00	%
Expected term of options (in years)		5.00 – 6.08			5.00 – 6.98

Stock Awards

Stock awards include rights to restricted stock awards with market-based vesting conditions and restricted stock units with service-based vesting conditions. Outstanding stock awards and related activity for the three months ended March 31, 2023 was as follows:

	*Number of Stock Awards*			*Weighted Average Grant Date Fair Value*
Unvested balance – December 31, 2022		769,139		$	9.84
Granted		43,479			1.15
Forfeited		(448	)		9.84
Unvested balance – March 31, 2023		812,170		$	9.38

As of March 31, 2023, we had approximately $0.1 million of unrecognized stock-based compensation costs related to non-vested stock awards which is expected to be recognized over a weighted-average period of 0.98 years. As of December 31, 2022, we had no unrecognized stock-based compensation costs related to non-vested stock awards.

Condensed Consolidated Balance Sheets (Current period Unaudited) (Parentheticals) - $ / shares	Mar. 31, 2023	Dec. 31, 2022	Dec. 30, 2020
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	77,987,349	74,759,591
Common stock, shares outstanding (in shares)	77,987,349	74,759,591

Note 6 - Accrued Liabilities

3 Months Ended

Mar. 31, 2023

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

Note 6. Accrued Liabilities

Accrued liabilities as of March 31, 2023 and December 31, 2022 were as follows:

	*March 31,*		*December 31,*
(in thousands)	*2023*		*2022*
Accrued compensation and benefits	$	2,638	$	2,007
Accrued CRO and clinical fees		2,752		1,297
Other		543		559
Total accrued liabilities	$	5,933	$	3,863

Note 9 - Commitments and Contingencies

3 Months Ended

Mar. 31, 2023

Commitments and Contingencies Disclosure [Text Block]

Note 9. 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 March 31, 2023 and December 31, 2022, we had commitments under various agreements for capital expenditures totaling $0.5 million and $1.6 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 $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 March 31, 2023, 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 condensed 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 6 - Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Accrued compensation and benefits	$ 2,638	$ 2,007
Accrued CRO and clinical fees	2,752	1,297
Other	543	559
Total accrued liabilities	$ 5,933	$ 3,863

Note 17 - Subsequent Events (Details Textual) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended
	Apr. 01, 2023	May 09, 2023	Mar. 31, 2023	Mar. 31, 2022
Proceeds from Issuance of Common Stock			$ 4,266	$ 0
Subsequent Event [Member]
Proceeds from Issuance of Common Stock	$ 400
Subsequent Event [Member] \| Lincoln Park [Member] \| Purchase Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)		400,000
Proceeds from Issuance of Common Stock		$ 400
Subsequent Event [Member] \| Lincoln Park [Member] \| Purchase Agreement [Member] \| Commitment Shares [Member]
Stock Issued During Period, Shares, New Issues (in shares)		2,893

Note 8 - Notes Payable and Convertible Notes Payable (Details Textual)			1 Months Ended				3 Months Ended		12 Months Ended
	Apr. 30, 2019 USD ($)	Feb. 28, 2019 USD ($)	Dec. 31, 2022 USD ($) $ / shares	May 31, 2022 USD ($)	Sep. 30, 2021 USD ($)	May 31, 2021 USD ($) $ / shares shares	Mar. 31, 2023 USD ($) $ / shares shares	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) $ / shares
Proceeds from Notes Payable, Total							$ 350,000	$ 0
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) \| shares							4,477,045
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							$ 10,000	10,000
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							12,000
Proceeds from Loans							$ 1,000,000.0
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%
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%
Interest Expense, Debt							$ 74,000
Debt Issuance Costs, Gross			$ 100,000						$ 100,000
Debt Instrument, Convertible, Minimum Increment of Principal for Exercise			$ 1,000,000.0						$ 1,000,000.0
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
Coupon Interest Expense							75,000
Amortization of Debt Issuance Costs and Discounts							$ 1,000
Debt Instrument, Interest Rate, Effective Percentage							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							$ 2,000	2,000
The 2021 Avenue Loan [Member] \| Avenue [Member]
Debt Instrument, Face Amount						$ 30,000,000.0
Debt Instrument, Interest Rate, Stated Percentage						3.25%
Interest Expense, Debt							$ 1,000,000.0	700,000
Debt Instrument, Convertible, Conversion Price (in dollars per share) \| $ / shares							$ 10.36
Debt Instrument, Interest Rate During Period							14.60%		14.10%
Debt Instrument, Interest Only Payments, Period (Month)						12 months
Debt Instrument, First Interest-only Period Extension (Month)						12 months
Debt Instrument, Term (Month)						42 months
Additional Payment at Debt Maturity, Percentage of Principal						4.25%
Additional Payment at Debt Maturity						$ 900,000
Debt Issuance Costs, Net							$ 600,000
Debt Issuance Costs Expensed							47,000
Debt Instrument, Convertible, Maximum Conversion Amount							5,000,000.0
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net			$ 200,000				100,000		$ 200,000
Debt Instrument, Covenant, Cash and Certain Cash Equivalents, Minimum						5,000,000.0
Warrants and Rights Outstanding						1,500,000
The 2021 Avenue Loan [Member] \| Avenue [Member] \| Convertible Notes Payable [Member]
Interest Expense, Debt							240,000	180,000
Coupon Interest Expense							177,000	123,000
Amortization of Debt Issuance Costs and Discounts							$ 63,000	$ 57,000
Debt Instrument, Interest Rate, Effective Percentage							20.17%	15.71%
The 2021 Avenue Loan [Member] \| Avenue [Member] \| Notes Payable, Tranche 1 [Member]
Proceeds from Notes Payable, Total					$ 5,000,000.0	15,000,000.0
The 2021 Avenue Loan [Member] \| Avenue [Member] \| Notes Payable, Tranche 2 [Member]
Debt Instrument, Unfunded Balance						$ 10,000,000.0
The 2021 Avenue Loan [Member] \| Avenue [Member] \| Prime Rate [Member]
Debt Instrument, Basis Spread on Variable Rate						6.60%

Note 16 - Segment Information (Tables)

3 Months Ended

Mar. 31, 2023

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

	*Three Months Ended March 31,*
(in thousands)	*2023*			*2022*
Drugs:
Revenue from external customers	$	—		$	—
Loss from operations		(10,798	)		(13,343	)
Supplements:
Revenue from external customers	$	107		$	30
Income from operations		66			7
Consolidated:
Revenue from external customers	$	107		$	30
Loss from operations		(10,732	)		(13,336	)

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

	*Three Months Ended March 31,*
(in thousands)	*2023*			*2022*
Segment loss from operations	$	(10,732	)	$	(13,336	)
Total other income (expense), net		(1,038	)		(18	)
Net loss before income taxes	$	(11,770	)	$	(13,354	)

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

	*March 31,*		*December 31,*
(in thousands)	*2023*		*2022*
Total assets:
Drugs	$	20,875	$	20,476
Supplements		272		386
Corporate		18,741		23,631
Consolidated	$	39,888	$	44,493

Note 11 - Benefit Plans (Details Textual) - USD ($)		3 Months Ended		12 Months Ended
Note 11 - Benefit Plans (Details Textual) - USD ($)	May 09, 2023	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)		16,205,404		15,260,297
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)		1,077,432
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 100,000		$ 0
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		11 months 23 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 0.99	$ 2.25
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 16,800,000		$ 18,200,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		2 years 4 months 9 days		2 years 6 months 29 days
The 2014 Stock Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)		5,367,340
The 2020 Stock Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)		12,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)		11,933,488
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)		66,512
Common Stock, Capital Shares Reserved for Future Issuance, (Increase) (Decrease) During Period (in shares)	6,400,000
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		$ 100,000	$ 100,000

Note 1 - Nature of the Business

3 Months Ended

Mar. 31, 2023

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 15).

Clene Nanomedicine, Inc. (“Clene Nanomedicine”) became a public company on December 30, 2020 (the “Closing Date”) when it completed a reverse recapitalization (the “Reverse Recapitalization”) with Tottenham Acquisition I Limited (“Tottenham”), Tottenham’s wholly-owned subsidiary and our predecessor, Chelsea Worldwide Inc., and Creative Worldwide Inc., a wholly-owned subsidiary of Chelsea Worldwide Inc. On the Closing Date, Chelsea Worldwide Inc. changed its name to Clene Inc. and listed its shares of common stock, par value $0.0001 per share (“Common Stock”) on the Nasdaq Capital Market (“Nasdaq”) under the symbol “CLNN.”

Going Concern

We incurred a loss from operations of $10.7 million and $13.3 million for the three months ended March 31, 2023 and 2022, respectively. Our accumulated deficit was $205.0 million and $193.2 million as of March 31, 2023 and December 31, 2022, respectively. Our cash, cash equivalents, and marketable securities totaled $18.4 million and $23.3 million as of March 31, 2023 and December 31, 2022, respectively, and net cash used in operating activities was $9.2 million and $13.1 million for the three months ended March 31, 2023 and 2022, 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 will not have sufficient cash and other resources on hand to sustain our current operations or meet our obligations as they become due unless we 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 8). 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 and equity purchase agreement. 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 March 31, 2023, we have raised $0.4 million through our equity purchase agreement. 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 condensed consolidated financial statements are issued.

The accompanying condensed 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 condensed 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 condensed 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 3 - Marketable Securities - Available for Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Amortized cost		$ 4,997
Gross unrealized gains		0
Gross unrealized losses		(14)
Fair value	$ 0	4,983
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 8 - Notes Payable and Convertible Notes Payable

3 Months Ended

Mar. 31, 2023

Debt Disclosure [Text Block]

Note 8. Notes Payable and Convertible Notes Payable

Our notes payable and convertible notes payable as of March 31, 2023 and December 31, 2022 was as follows:

	*Stated*			*March 31,*			*December 31,*
(in thousands, except interest rates)	*Interest Rate*			*2023*			*2022*
Notes payable
Advance Cecil, Inc. (commenced April 2019)		8.00	%	$	132		$	130
Maryland DHCD (commenced February 2019)		8.00	%		664			654
Maryland DHCD (commenced May 2022)		6.00	%		1,032			682
Avenue Venture Opportunities Fund, L.P. (commenced May 2021)		14.60	%		15,000			15,000
					16,828			16,466
Accrued and unpaid interest					35			22
Less unamortized discount and debt issuance costs					(399	)		(587	)
Less notes payable, current portion, net of unamortized discount and debt issuance costs					(9,751	)		(6,418	)
Total notes payable, net of current portion				$	6,713		$	9,483

Convertible notes payable
Avenue Venture Opportunities Fund, L.P. (commenced May 2021)		14.60	%	$	5,000		$	5,000
Maryland DHCD (commenced December 2022)		6.00	%		5,000			5,000
					10,000			10,000
Accrued and unpaid interest					83			7
Less unamortized discount and debt issuance costs					(176	)		(237	)
Total convertible notes payable				$	9,907		$	9,770

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, for a term loan of $0.5 million bearing simple interest at an annual rate of 8.00%. We are subject to covenants until maturity, including 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. We are not in violation of any covenants. The 2019 MD Loan established “Phantom Shares” 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 (i) principal plus accrued interest or (ii) the Phantom Shares multiplied by the closing price of our Common Stock on Nasdaq at the end of each reporting period. As of March 31, 2023 and December 31, 2022, the 2019 MD Loan was recorded at principal plus accrued interest as it was greater than the value of the Phantom Shares. We recognized interest expense of $10,000 and $10,000 for the three months ended March 31, 2023 and 2022, 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 our production activities. As of March 31, 2023, we had drawn $1.0 million under the term loan, with the remainder available for future Asset purchases until May 17, 2024. The first twelve payments, commencing July 1, 2022, are deferred, followed by eighteen monthly installments of interest-only based on the amount advanced under the loan, each up to a maximum amount of $15,000; followed by monthly installments of principal and interest in the amount of $33,306, payable for the lesser of thirty months or until the principal and accrued and unpaid interest is fully repaid, with a balloon payment of all remaining principal and accrued and unpaid interest due on the maturity date of July 1, 2027. We incurred $31,000 of debt issuance costs which were recorded as a debt discount. Under a priority of liens agreement by and between DHCD and Avenue, an existing secured creditor of the Company, DHCD was granted a continuing security interest in the Assets as collateral which shall be a first priority lien. We recognized interest expense of $12,000 for the three months ended March 31, 2023.

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 first twelve payments, commencing January 1, 2023, are deferred, followed by 48 monthly installments of interest-only, with a balloon payment of all principal and accrued and unpaid interest due on the maturity date of January 1, 2028. We incurred $0.1 million of debt issuance costs which were recorded as a debt discount. At any time after December 8, 2023, DHCD may, in its sole discretion, convert any portion of the outstanding principal into Common Stock in increments of $1.0 million, at a price equal to the greater of: (i) 97% of the 30-day trailing VWAP of our Common Stock, ending on and including the conversion date; or (ii) $4.00 per share (the “DHCD Conversion Feature”). The DHCD Conversion Feature did not meet the requirements for derivative accounting. For the three months ended March 31, 2023, we recognized (i) total interest expense of $74,000, (ii) coupon interest expense of $75,000, and (iii) amortization of debt issuance costs of ($1,000), 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, for a term loan of $0.1 million bearing simple interest at an annual rate of 8.00%. The 2019 Cecil Loan established “Phantom Shares” 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 (i) principal plus accrued interest or (ii) the Phantom Shares multiplied by the closing price of our Common Stock on Nasdaq at the end of each reporting period. As of March 31, 2023 and December 31, 2022, the 2019 Cecil Loan was recorded at principal plus accrued interest as it was greater than the value of the Phantom Shares. We recognized interest expense of $2,000 and $2,000 for the three months ended March 31, 2023 and 2022, respectively.

Avenue Loan

In May 2021, we entered into a loan agreement (the “2021 Avenue Loan”) with Avenue for a term loan of up to $30.0 million, bearing interest at a variable rate equal to (i) the greater of (a) the prime rate or (b) 3.25%, plus (ii) 6.60%. As of March 31, 2023 and December 31, 2022, the interest rate was 14.60% and 14.10%, respectively. The first tranche consisted of $15.0 million funded in May 2021 plus $5.0 million funded in September 2021 (“Tranche 1”). The remaining unfunded $10.0 million (“Tranche 2”) was not drawn and expired on December 31, 2022. Payments are interest-only for the first twelve months and were extended an additional twelve months due to our achievement of a statistically significant result in certain clinical trials, followed by equal monthly installments of principal plus interest payments at the variable rate then in effect until the end of the 42-month term on December 1, 2024. An additional payment of 4.25% of the funded principal, equal to $0.9 million (the “Final Payment”), is due at maturity and was recorded as a debt premium. We incurred $0.6 million of debt issuance costs of which $47,000 was expensed immediately and the remainder was recorded as a debt discount.

At any time between May 21, 2022 and May 21, 2024, Avenue may, in its sole discretion, convert up to $5.0 million of outstanding principal into Common Stock at a price per share equal to $10.36 (the “Avenue Conversion Feature”), subject to certain minimum price and volume restrictions related to our Common Stock on Nasdaq. The Final Payment and Avenue Conversion Feature did not meet the requirements for derivative accounting. As of March 31, 2023 and December 31, 2022, unamortized debt discount and issuance costs related to the convertible note were $0.1 million and $0.2 million, respectively. For the convertible note for the three months ended March 31, 2023 and 2022, we recognized (i) total interest expense of $240,000 and $180,000, respectively; (ii) coupon interest expense of $177,000 and $123,000, respectively; and (iii) amortization of debt discount and issuance costs of $63,000 and $57,000, respectively; and the effective interest rate was 20.17% and 15.71%, respectively.

We are subject to covenants until maturity, including limitations on our ability to retire, repurchase, or redeem our Common Stock, options, and warrants other than per the terms of the securities; limitations on our ability to pay dividends of cash or property; and we are required to maintain unrestricted cash and cash equivalents of at least $5.0 million. We are not in violation of any covenants. Under the 2021 Avenue Loan, Avenue also has the ability to immediately accelerate all obligations under the 2021 Avenue Loan upon the occurrence of certain events of default or material adverse effects. 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. We recognized interest expense of $1.0 million and $0.7 million for the three months ended March 31, 2023 and 2022, respectively.

Additionally, we issued a warrant to purchase Common Stock to Avenue based on the amount of funded principal, equal to 115,851 shares of Common Stock at an exercise price of $8.63 per share (the “Avenue Warrant”). A portion of net proceeds from the issuance of the 2021 Avenue Loan were allocated to the Avenue Warrant in an amount equal to its fair value of $1.5 million, which was recorded as a debt discount.

Debt Maturities

Future principal payments, net of unamortized discounts, and without giving effect to any potential future exercise of conversion features, are as follows:

(in thousands)	2019 MD Loan		2019 Cecil Loan		2021 Avenue Loan			2022 MD Loan			2022 DHCD Loan
2023 (remainder)	$	—	$	—	$	6,667		$	—		$	—
2024		—		—		13,333			—			—
2025		—		—		—			347			—
2026		—		—		—			369			—
2027		—		—		—			317			—
2028		—		—		—			—			5,000
Thereafter		664		132		—			—			—
Subtotal of future principal payments		664		132		20,000			1,033			5,000
Accrued and unpaid interest		—		—		—			35			83
Less unamortized discount and debt issuance costs		—		—		(497	)		(26	)		(52	)
Total	$	664	$	132	$	19,503		$	1,042		$	5,031

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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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/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Note 8 - Note Payable and Convertible Notes Payable - Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Less notes payable, current portion, net of unamortized discount and debt issuance costs	$ (9,751)	$ (6,418)
Notes payable, net of current portion	6,713	9,483
Convertible notes payable	9,907	9,770
Notes Payable [Member]
Total	16,828	16,466
Notes payable	16,828	16,466
Accrued and unpaid interest	35	22
Less unamortized discount and debt issuance costs	(399)	(587)
Less notes payable, current portion, net of unamortized discount and debt issuance costs	(9,751)	(6,418)
Notes payable, net of current portion	6,713	9,483
Convertible Notes Payable [Member]
Total	10,000	10,000
Notes payable	10,000	10,000
Accrued and unpaid interest	83	7
Less unamortized discount and debt issuance costs	(176)	(237)
Convertible notes payable	$ 9,907	9,770
The 2019 Cecil Loan [Member] \| Notes Payable [Member]
Interest Rate	8.00%
Total	$ 132	130
Notes payable	132	130
Accrued and unpaid interest	$ 0
The 2019 Maryland DHCD [Member] \| Notes Payable [Member]
Interest Rate	8.00%
Total	$ 664	654
Notes payable	$ 664	654
The 2022 Maryland DHCD [Member] \| Notes Payable [Member]
Interest Rate	6.00%
Total	$ 1,032	682
Notes payable	$ 1,032	682
Avenue [Member] \| Notes Payable [Member]
Interest Rate	14.60%
Total	$ 15,000	15,000
Notes payable	$ 15,000	15,000
Avenue [Member] \| Convertible Notes Payable [Member]
Interest Rate	14.60%
Total	$ 5,000	5,000
Notes payable	5,000	5,000
The 2022 DHCD Loan [Member] \| Notes Payable [Member]
Total	5,031
Notes payable	5,031
Accrued and unpaid interest	$ 83
The 2022 DHCD Loan [Member] \| Convertible Notes Payable [Member]
Interest Rate	6.00%
Total	$ 5,000	5,000
Notes payable	$ 5,000	$ 5,000

Note 5 - Property and Equipment, Net (Tables)

3 Months Ended

Mar. 31, 2023

Property, Plant and Equipment [Table Text Block]

	*March 31,*			*December 31,*
(in thousands)	*2023*			*2022*
Lab equipment	$	3,923		$	3,934
Office equipment		178			177
Computer software		459			459
Leasehold improvements		9,966			5,677
Construction in progress		1,652			5,664
		16,178			15,911
Less accumulated depreciation		(5,664	)		(5,273	)
Total property and equipment, net	$	10,514		$	10,638

Depreciation Of Property Plant And Equipment [Table Text Block]

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
General and administrative	$	67	$	29
Research and development		335		166
Total depreciation expense	$	402	$	195

Note 7 - Leases - Components of Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Amortization	$ 20	$ 20
Interest on lease liabilities	6	5
Operating lease costs	253	230
Variable lease costs	50	65
Total lease costs	$ 329	$ 320

Note 15 - Related Party Transactions (Details Textual) - 4Life [Member] - Supply Agreement [Member]	1 Months Ended
	Aug. 31, 2018
Related Party Transaction, Exclusive License Term (Year)	5 years
Related Party Transaction, Royalty Fee Rate for Revenues	3.00%

Note 3 - Marketable Securities (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Debt Securities, Available-for-Sale, Total	$ 0		$ 4,983
Proceeds from Sale and Maturity of Debt Securities, Available-for-Sale	$ 5,000	$ 0
Debt Securities, Available-for-Sale, Allowance for Credit Loss			$ 0

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenue:
Total revenue	$ 107	$ 30
Operating expenses:
Cost of revenue	5	0
Research and development	7,395	8,580
General and administrative	3,439	4,786
Total operating expenses	10,839	13,366
Loss from operations	(10,732)	(13,336)
Other income (expense), net:
Interest income	172	24
Interest expense	(1,066)	(782)
Gain on termination of lease	0	420
Commitment share expense	(399)	0
Change in fair value of common stock warrant liability	0	(18)
Change in fair value of Clene Nanomedicine contingent earn-out liability	(55)	(57)
Change in fair value of Initial Stockholders contingent earn-out liability	(7)	(12)
Research and development tax credits and unrestricted grants	314	299
Other income (expense), net	3	108
Total other income (expense), net	(1,038)	(18)
Net loss before income taxes	(11,770)	(13,354)
Income tax expense	0	0
Net loss	(11,770)	(13,354)
Other comprehensive income:
Unrealized gain (loss) on available-for-sale securities	14	(50)
Foreign currency translation adjustments	4	50
Total other comprehensive income	18	0
Comprehensive loss	$ (11,752)	$ (13,354)
Net loss per share – basic and diluted (in dollars per share)	$ (0.15)	$ (0.21)
Weighted average common shares used to compute basic and diluted net loss per share (in shares)	76,049,665	62,852,863
Product [Member]
Revenue:
Total revenue	$ 64	$ 7
Royalty [Member]
Revenue:
Total revenue	$ 43	$ 23

Note 9 - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Sep. 30, 2019	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Government Assistance, Amount		$ 314	$ 299
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		$ 500		$ 1,600

Significant Accounting Policies (Policies)	3 Months Ended
Significant Accounting Policies (Policies)	Mar. 31, 2023
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	*Basis of Presentation* The accompanying condensed consolidated financial statements include the accounts of Clene Inc. and our wholly-owned subsidiaries, Clene Nanomedicine, Inc., 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 condensed consolidated financial statements in accordance with United States (“U.S.”) Generally Accepted Accounting Principles (“GAAP”) for interim financial reporting and as required by Regulation S-X, Rule 10-01. The condensed consolidated financial statements have been prepared on the same basis as our audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which are normal and recurring in nature, necessary for fair financial statement presentation. The financial data and other information disclosed in the condensed consolidated financial statements and related notes for the three months ended March 31, 2023 and 2022 are unaudited. Results of operations for the three months ended March 31, 2023 and 2022 are not necessarily indicative of the results for the entire fiscal year or any other period. The condensed consolidated financial statements for the three months ended March 31, 2023 and 2022 should be read in conjunction with the audited consolidated financial statements included in our Annual Report on Form 10-K.
Use of Estimates, Policy [Policy Text Block]	*Use of Estimates* The preparation of condensed 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 condensed 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 held in financial institutions and 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 is classified as current and noncurrent on the condensed 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 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.
Inventory, Policy [Policy Text Block]	*Inventory* Inventory is stated at historic cost on a first-in first-out basis. Our inventory consisted of $0.1 million in raw materials and $19,000 in finished goods as of March 31, 2023, and $29,000 in raw material and $14,000 in finished goods as of December 31, 2022. Inventory 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 condensed 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.
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 condensed consolidated statements of operations and comprehensive loss.
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 condensed consolidated balance sheets. We recognize lease expense for these short-term leases on a straight-line basis over the lease term in the condensed 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 condensed 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 of Clene Nanomedicine’s stockholders are entitled to receive additional shares (the “Clene Nanomedicine Contingent Earn-out”) of Common Stock as follows: (i) 3,338,483 shares of Common Stock if (a) the volume-weighted average price (“VWAP”) 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 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) 2,503,851 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 Reverse Recapitalization (the requirements in (a) and (b) collectively, “Milestone 2”). If Milestone 1 is not achieved but Milestone 2 is achieved, the Clene Nanomedicine stockholders will receive an additional issuance equal to Milestone 1. Tottenham’s former officers and directors, sponsor, and public stockholders (the “Initial Stockholders”) are entitled to receive earn-out shares (the “Initial Stockholders Contingent Earn-out,” and collectively with the Clene Nanomedicine Contingent Earn-out, the “Contingent Earn-outs”) as follows: (i) 375,000 shares of Common Stock upon the achievement of Milestone 1; and (ii) 375,000 shares of Common Stock upon achievement of Milestone 2. If Milestone 1 is not achieved but Milestone 2 is achieved, the Initial Stockholders will receive an additional issuance equal to Milestone 1. In accordance with ASC 815, the Contingent Earn-outs are not indexed to our own stock and therefore were accounted for as a liability at the Reverse Recapitalization date and are subsequently remeasured to fair value at each reporting date with changes 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.
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 condensed consolidated statements of operations and comprehensive loss. We accrue certain research and development tax credits receivable in other current assets (see Note 4) in the condensed 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 condensed 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 condensed 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 condensed consolidated balance sheets if the conditions or performance obligations are expected to be met within the next twelve months. We did not fulfill any grant conditions or performance obligations during the three months ended March 31, 2023 and 2022.
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 condensed 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 (deficit) is translated using historical rates. Adjustments resulting from the translation of the condensed 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 (deficit). 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 (deficit) 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 gain (loss) on available-for-sale securities.
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 condensed 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 condensed 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 condensed 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. 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 Nasdaq on the date of grant. The fair value of stock awards with market conditions are determined using a Monte Carlo valuation model.
New Accounting Pronouncements, Policy [Policy Text Block]	*Recently Adopted Accounting Pronouncements* 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 was effective for our fiscal years beginning after December 15, 2022. The adoption of this guidance did not have an impact on our condensed consolidated financial statements.

Note 7 - Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating cash flows from operating leases	$ (303)	$ (295)
Operating cash flows from finance leases	(6)	(5)
Payments of finance lease obligations	$ (28)	$ (32)

Note 5 - Property and Equipment, Net

3 Months Ended

Mar. 31, 2023

Property, Plant and Equipment Disclosure [Text Block]

Note 5. Property and Equipment, Net

Property and equipment, net, as of March 31, 2023 and December 31, 2022 were as follows:

	*March 31,*			*December 31,*
(in thousands)	*2023*			*2022*
Lab equipment	$	3,923		$	3,934
Office equipment		178			177
Computer software		459			459
Leasehold improvements		9,966			5,677
Construction in progress		1,652			5,664
		16,178			15,911
Less accumulated depreciation		(5,664	)		(5,273	)
Total property and equipment, net	$	10,514		$	10,638

Depreciation expense recorded in research and development expense and general and administrative expense for the three months ended March 31, 2023 and 2022 was as follows:

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
General and administrative	$	67	$	29
Research and development		335		166
Total depreciation expense	$	402	$	195

Note 12 - Fair Value - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Clene Nanomedicine contingent earn-out liability	$ 2,319		$ 2,264
Initial Stockholders contingent earn-out liability	298		291
Fair value	0		4,983
Commercial Paper [Member]
Fair value			3,482
Corporate Debt Securities [Member]
Fair value			1,501
Fair Value, Inputs, Level 1 [Member]
Clene Nanomedicine contingent earn-out liability	0		0
Initial Stockholders contingent earn-out liability	0		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 2 [Member]
Clene Nanomedicine contingent earn-out liability	0		0
Initial Stockholders contingent earn-out liability	0		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 3 [Member]
Clene Nanomedicine contingent earn-out liability	2,319		2,264
Initial Stockholders contingent earn-out liability	298		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
Money Market Funds [Member]
Cash Equivalents	15,981		14,317
Money Market Funds [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash Equivalents	15,981		14,317
Money Market Funds [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash Equivalents	0		0
Money Market Funds [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash Equivalents	0		$ 0
Clene Nanomedicine Contingent Earn-out [Member]
Balance	2,264	$ 18,100
Change in fair value	55	57
Balance – March 31, 2023	2,319	18,157
Reclassification from liability to equity		0
Initial Stockholders Contingent Earn-out [Member]
Balance	291	2,317
Change in fair value	7	12
Balance – March 31, 2023	$ 298	2,329
Reclassification from liability to equity		0
Common Stock Warrant Liability [Member]
Balance		474
Change in fair value		18
Balance – March 31, 2023		187
Reclassification from liability to equity		$ (305)

Note 14 - Net Loss Per Share

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Text Block]

Note 14. Net Loss Per Share

The computation of basic and diluted net loss per share attributable to common stockholders for the three months ended March 31, 2023 and 2022 was as follows:

	*Three Months Ended March 31,*
(in thousands, except share and per share data)	*2023*			*2022*
Numerator:
Net loss attributable to common stockholders	$	(11,770	)	$	(13,354	)
Denominator:
Weighted average common shares outstanding		76,049,665			62,852,863
Net loss per share attributable to common stockholders – basic and diluted	$	(0.15	)	$	(0.21	)

The following shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the three months ended March 31, 2023 and 2022 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:

	*Three Months Ended March 31,*
	*2023*		*2022*
Convertible notes payable (see Note 8)		1,732,703		482,703
Common stock warrants (see Note 13)		4,477,045		4,477,045
Options to purchase common stock (see Note 11)		16,205,404		11,944,789
Unvested restricted stock awards (see Note 11)		812,170		914,876
Contingent earn-out shares (see Note 2)		6,592,334		6,592,334
Total		29,819,656		24,411,747

Note 11 - Benefit Plans - Activity Related to Restricted Stock Awards (Details)	3 Months Ended
	Mar. 31, 2023 $ / shares shares
Granted, number of restricted stock awards (in shares) \| shares	43,479
Granted, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 1.15
Restricted Stock [Member]
Unvested balance, number of restricted stock awards (in shares) \| shares	769,139
Unvested balance, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 9.84
Forfeited, number of restricted stock awards (in shares) \| shares	(448)
Forfeited, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 9.84
Unvested balance, number of restricted stock awards (in shares) \| shares	812,170
Unvested balance, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 9.38

Note 7 - Leases

3 Months Ended

Mar. 31, 2023

Lessee, Operating and Finance Leases [Text Block]

Note 7. 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

Operating leases primarily consist of real estate leases for office and laboratory space. We have three real estate leases: (i) a laboratory and manufacturing facility which commenced in September 2021 with a ten-year term and an option to extend for two five-year periods; (ii) a laboratory and manufacturing facility which commenced in February 2022 with a seven-year term and an option to extend for two five-year periods, which replaced a previous lease for the same facility and resulted a gain on termination of $0.4 million for the year ended December 31, 2022; and (iii) our corporate office which commenced a renewed term in September 2022 for seven years with an option to extend for five years. We did not recognize the payments to be made in the option periods as part of the right-of-use asset or lease liability because the exercise of the option is not reasonably certain.

As of March 31, 2023 and December 31, 2022, our operating lease obligations had a weighted-average discount rate of 9.6% and 9.6%, respectively; and a weighted-average remaining term of 7.1 years and 7.3 years, respectively.

Finance Leases

Assets recorded under finance lease obligations and included in property and equipment as of March 31, 2023 and December 31, 2022 were as follows:

	*March 31,*			*December 31,*
(in thousands)	*2023*			*2022*
Lab equipment	$	408		$	408
Work in process		228			228
Total		636			636
Less accumulated depreciation		(346	)		(326	)
Net	$	290		$	310

As of March 31, 2023 and December 31, 2022, our finance lease obligations had a weighted-average interest rate of 10.8% and 10.2%, respectively; and a weighted-average remaining term of 1.0 years and 1.2 years, respectively.

Maturity Analysis of Leases

The maturity analysis of our finance and operating leases as of March 31, 2023 was as follows:

(in thousands)	*Finance Leases*			*Operating Leases*
2023 (remainder)	$	65		$	767
2024		27			1,171
2025		—			1,202
2026		—			1,231
2027		—			1,129
2028		—			1,092
Thereafter		—			1,694
Total undiscounted cash flows		92			8,286
Less amount representing interest/discounting		(13	)		(2,379	)
Present value of future lease payments		79			5,907
Less lease obligations, current portion		(76	)		(508	)
Lease obligations, long term portion	$	3		$	5,399

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 three months ended March 31, 2023 and 2022 were as follows:

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
Finance lease costs:
Amortization	$	20	$	20
Interest on lease liabilities		6		5
Operating lease costs		253		230
Variable lease costs		50		65
Total lease costs	$	329	$	320

Supplemental Cash Flow Information

	*Three Months Ended March 31,*
(in thousands)	*2023*			*2022*
Operating cash flows from operating leases	$	(303	)	$	(295	)
Operating cash flows from finance leases	$	(6	)	$	(5	)
Financing cash flows from finance leases	$	(28	)	$	(32	)

Note 16 - Segment Information - Reconciliation of the Reportable Segments' Loss From Operations to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Segment loss from operations	$ (10,732)	$ (13,336)
Total other income (expense), net	(1,038)	(18)
Net loss before income taxes	$ (11,770)	$ (13,354)

Note 15 - Related Party Transactions - Revenue From 4Life Agreement (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenue	$ 107	$ 30
Related Party [Member]
Revenue	106	23
Product [Member]
Revenue	64	7
Product [Member] \| Related Party [Member]
Revenue	63	0
Royalty [Member]
Revenue	43	23
Royalty [Member] \| Related Party [Member]
Revenue	$ 43	$ 23

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Note 12 - Fair Value (Tables)

3 Months Ended

Mar. 31, 2023

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

	*March 31, 2023*
(in thousands)	*Level 1*		*Level 2*		*Level 3*		*Total*
Cash equivalents
Money market funds	$	15,981	$	—	$	—	$	15,981
Clene Nanomedicine contingent earn-out liability		—		—		2,319		2,319
Initial Stockholders contingent earn-out liability		—		—		298		298

	*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

(in thousands)	*Clene Nanomedicine Contingent Earn-out*		*Initial Stockholders Contingent Earn-out*
Balance – December 31, 2022	$	2,264	$	291
Change in fair value		55		7
Balance – March 31, 2023	$	2,319	$	298

(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		18			57		12
Reclassification from liability to equity		(305	)		—		—
Balance – March 31, 2022	$	187		$	18,157	$	2,329

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

	*March 31,*			*December 31,*
	*2023*			*2022*
Expected stock price volatility		115.00	%		115.00	%
Risk-free interest rate		3.90	%		4.20	%
Expected dividend yield		0.00	%		0.00	%
Expected term (in years)		2.75			3.00

Note 2 - Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2023

Significant Accounting Policies [Text Block]

Note 2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying condensed consolidated financial statements include the accounts of Clene Inc. and our wholly-owned subsidiaries, Clene Nanomedicine, Inc., 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 condensed consolidated financial statements in accordance with United States (“U.S.”) Generally Accepted Accounting Principles (“GAAP”) for interim financial reporting and as required by Regulation S-X, Rule 10-01. The condensed consolidated financial statements have been prepared on the same basis as our audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which are normal and recurring in nature, necessary for fair financial statement presentation. The financial data and other information disclosed in the condensed consolidated financial statements and related notes for the three months ended March 31, 2023 and 2022 are unaudited.

Results of operations for the three months ended March 31, 2023 and 2022 are not necessarily indicative of the results for the entire fiscal year or any other period. The condensed consolidated financial statements for the three months ended March 31, 2023 and 2022 should be read in conjunction with the audited consolidated financial statements included in our Annual Report on Form 10-K.

Use of Estimates

The preparation of condensed 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 condensed 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 held in financial institutions and 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 is classified as current and noncurrent on the condensed 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 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.

Inventory

Inventory is stated at historic cost on a first-in first-out basis. Our inventory consisted of $0.1 million in raw materials and $19,000 in finished goods as of March 31, 2023, and $29,000 in raw material and $14,000 in finished goods as of December 31, 2022. Inventory 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 condensed 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.

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 condensed consolidated statements of operations and comprehensive loss.

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 condensed consolidated balance sheets. We recognize lease expense for these short-term leases on a straight-line basis over the lease term in the condensed 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 condensed 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 of Clene Nanomedicine’s stockholders are entitled to receive additional shares (the “Clene Nanomedicine Contingent Earn-out”) of Common Stock as follows: (i) 3,338,483 shares of Common Stock if (a) the volume-weighted average price (“VWAP”) 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 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) 2,503,851 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 Reverse Recapitalization (the requirements in (a) and (b) collectively, “Milestone 2”). If Milestone 1 is not achieved but Milestone 2 is achieved, the Clene Nanomedicine stockholders will receive an additional issuance equal to Milestone 1. Tottenham’s former officers and directors, sponsor, and public stockholders (the “Initial Stockholders”) are entitled to receive earn-out shares (the “Initial Stockholders Contingent Earn-out,” and collectively with the Clene Nanomedicine Contingent Earn-out, the “Contingent Earn-outs”) as follows: (i) 375,000 shares of Common Stock upon the achievement of Milestone 1; and (ii) 375,000 shares of Common Stock upon achievement of Milestone 2. If Milestone 1 is not achieved but Milestone 2 is achieved, the Initial Stockholders will receive an additional issuance equal to Milestone 1.

In accordance with ASC 815, the Contingent Earn-outs are not indexed to our own stock and therefore were accounted for as a liability at the Reverse Recapitalization date and are subsequently remeasured to fair value at each reporting date with changes 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.

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 condensed consolidated statements of operations and comprehensive loss. We accrue certain research and development tax credits receivable in other current assets (see Note 4) in the condensed 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 condensed 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 condensed 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 condensed consolidated balance sheets if the conditions or performance obligations are expected to be met within the next twelve months. We did not fulfill any grant conditions or performance obligations during the three months ended March 31, 2023 and 2022.

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 condensed 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 (deficit) is translated using historical rates.

Adjustments resulting from the translation of the condensed 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 (deficit). 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 (deficit) 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 gain (loss) on available-for-sale securities.

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 condensed 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 condensed 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 condensed 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. 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 Nasdaq on the date of grant. The fair value of stock awards with market conditions are determined using a Monte Carlo valuation model.

Recently Adopted Accounting Pronouncements

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 was effective for our fiscal years beginning after December 15, 2022. The adoption of this guidance did not have an impact on our condensed consolidated financial statements.

Note 11 - Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2023

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

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
General and administrative	$	1,250	$	1,458
Research and development		973		744
Total stock-based compensation expense	$	2,223	$	2,202

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
Stock options	$	2,222	$	2,202
Stock awards		1		—
Total stock-based compensation expense	$	2,223	$	2,202

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, 2022		15,260,297		$	2.98		7.28	$	2,348
Granted		1,077,432			1.30		9.89		—
Forfeited		(132,325	)		5.83		—		—
Outstanding – March 31, 2023		16,205,404		$	2.85		7.22	$	2,923
Vested and exercisable – March 31, 2023		8,085,513		$	2.76		5.29	$	2,855
Vested, exercisable or expected to vest – March 31, 2023		16,205,404		$	2.85		7.22	$	2,923

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

	*Three Months Ended March 31,*
	*2023*			*2022*
Expected stock price volatility		96.22% – 103.24%			89.57% – 93.07%
Risk-free interest rate		3.38% – 3.98%			1.65% – 2.02%
Expected dividend yield		0.00	%		0.00	%
Expected term of options (in years)		5.00 – 6.08			5.00 – 6.98

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

	*Number of Stock Awards*			*Weighted Average Grant Date Fair Value*
Unvested balance – December 31, 2022		769,139		$	9.84
Granted		43,479			1.15
Forfeited		(448	)		9.84
Unvested balance – March 31, 2023		812,170		$	9.38

Note 13 - Capital Stock (Details Textual) - USD ($)					1 Months Ended	3 Months Ended		12 Months Ended
Note 13 - Capital Stock (Details Textual) - USD ($)	Apr. 01, 2023	Mar. 03, 2023	Apr. 14, 2022	Dec. 30, 2020	Oct. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	May 09, 2023	May 31, 2021
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
Preferred Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.0001
Common Stock, Shares, Issued (in shares)						77,987,349		74,759,591
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 Issuance of Common Stock						$ 4,266,000	$ 0
Purchase Price, Sales						$ 0
Common Stock, Shares, Outstanding (in shares)						77,987,349		74,759,591
Preferred Stock, Shares Outstanding (in shares)						0		0
Lincoln Park Capital Fund, LLC [Member]
Stock Issued During Period, Shares, New Issues (in shares)		332,668
Purchase Agreement, Commencing Period (Month)		36 months
Purchase Agreement, Regular Purchase (in shares)		75,000
Purchase Agreement, Regular Purchase, Shares, Closing Price One (in shares)		100,000
Purchase Agreement, Closing Price One (in dollars per share)		$ 1.00
Purchase Agreement, Regular Purchase, Shares, Closing Price Two (in shares)		150,000
Purchase Agreement, Closing Price Two (in dollars per share)		$ 2.00
Purchase Agreement, Regular Purchase, Shares, Closing Price Three (in shares)		200,000
Purchase Agreement, Closing Price Three (in dollars per share)		$ 4.00
Purchase Agreement, Accelerated Purchase, Maximum Percentage of Regular Purchase		300.00%
Purchase Agreement, Accelerated Purchase, Maximum Percentage Of Prior Day Volume		30.00%
Purchase Agreement, Additional Accelerated Purchase, Maximum Percentage of Regular Purchase		300.00%
Purchase Agreement, Additional Accelerated Purchase, Maximum Percentage of Prior Day Volume		30.00%
Purchase Agreement, Price Discount of Additional Purchases		97.00%
Derivative, Notional Amount		$ 0
Purchase Agreement, Additional Commitment Shares (in shares)		166,334
Purchase Agreement, Shares Sell Limitation (in shares)		15,310,115
Purchase Agreement, Shares Sell Limitation, Percentage Of Outstanding Shares		19.99%
Percentage of Common Stock Beneficial Ownership		4.99%
Lincoln Park Capital Fund, LLC [Member] \| Maximum [Member]
Purchase Agreement, Amount Of Shares Commit To Purchase		$ 25,000,000.0
Percentage of Common Stock Beneficial Ownership		9.99%
Lincoln Park Capital Fund, LLC [Member] \| Minimum [Member]
Purchase Agreement, Minimum Average Price Per Share To Avoid Sell Limitation (in dollars per share)		$ 1.2404
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)						2,895,090
Proceeds from Issuance of Common Stock						$ 4,500,000
Aggregate Offering Price			$ 50,000,000.0
Fixed Commission Rate Percentage			3.00%
Payments for Commissions						$ 100,000
Warrants with Tranche 2 of 2021 Avenue Loan [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)										115,851
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 with Tranche 2 of 2021 Avenue Loan [Member]
Class of Warrant or Right, Exercised During Period (in shares)						0		0
Subsequent Event [Member]
Common Stock, Shares Authorized (in shares)									300,000,000
Proceeds from Issuance of Common Stock	$ 400,000

Note 15 - Related Party Transactions

3 Months Ended

Mar. 31, 2023

Note 15. 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 three months ended March 31, 2023 and 2022 was as follows:

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
Product revenue from related parties	$	63	$	—
Royalty revenue from related parties		43		23
Total revenue from related parties	$	106	$	23

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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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/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Note 3 - Marketable Securities

3 Months Ended

Mar. 31, 2023

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

Note 3. Marketable Securities

Available-for-Sale Securities

We had no available-for-sale securities as of March 31, 2023. 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

We received proceeds from maturities of available-for-sale securities of $5.0 million and $0 for the three months ended March 31, 2023 and 2022, respectively. As of December 31, 2022, we did not have any allowance for credit losses or impairments of available-for-sale securities.

Note 8 - Notes Payable and Convertible Notes Payable - Schedule of Future Payments (Details) - Notes Payable [Member] - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Accrued and unpaid interest	$ 35	$ 22
Total	16,828	16,466
The 2019 MD Loan [Member]
2023 (remainder)	0
2024	0
2025	0
2026	0
2027	0
2028	0
Thereafter	664
Subtotal of future principal payments	664
Accrued and unpaid interest	0
Less unamortized discount and debt issuance costs	0
Total	664
The 2019 Cecil Loan [Member]
2023 (remainder)	0
2024	0
2025	0
2026	0
2027	0
2028	0
Thereafter	132
Subtotal of future principal payments	132
Accrued and unpaid interest	0
Less unamortized discount and debt issuance costs	0
Total	132	$ 130
The 2021 Avenue Loan [Member]
2023 (remainder)	6,667
2024	13,333
2025	0
2026	0
2027	0
2028	0
Thereafter	0
Subtotal of future principal payments	20,000
Accrued and unpaid interest	0
Less unamortized discount and debt issuance costs	(497)
Total	19,503
The 2022 MD Loan [Member]
2023 (remainder)	0
2024	0
2025	347
2026	369
2027	317
2028	0
Thereafter	0
Subtotal of future principal payments	1,033
Accrued and unpaid interest	35
Less unamortized discount and debt issuance costs	(26)
Total	1,042
The 2022 DHCD Loan [Member]
2023 (remainder)	0
2024	0
2025	0
2026	0
2027	0
2028	5,000
Thereafter	0
Subtotal of future principal payments	5,000
Accrued and unpaid interest	83
Less unamortized discount and debt issuance costs	(52)
Total	$ 5,031

Note 7 - Leases - Assets Recorded Under Finance Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Finance lease asset, gross	$ 636	$ 636
Less accumulated depreciation	(346)	(326)
Net	290	310
Equipment [Member]
Finance lease asset, gross	408	408
Construction in Progress [Member]
Finance lease asset, gross	$ 228	$ 228

Note 12 - Fair Value

3 Months Ended

Mar. 31, 2023

Fair Value Disclosures [Text Block]

Note 12. Fair Value

Cash, cash equivalents, and marketable securities 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. Our remaining fair value measures are discussed below.

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 March 31, 2023 is as follows:

	*March 31, 2023*
(in thousands)	*Level 1*		*Level 2*		*Level 3*		*Total*
Cash equivalents
Money market funds	$	15,981	$	—	$	—	$	15,981
Clene Nanomedicine contingent earn-out liability		—		—		2,319		2,319
Initial Stockholders contingent earn-out liability		—		—		298		298

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

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 three months ended March 31, 2023 were as follows:

(in thousands)	*Clene Nanomedicine Contingent Earn-out*		*Initial Stockholders Contingent Earn-out*
Balance – December 31, 2022	$	2,264	$	291
Change in fair value		55		7
Balance – March 31, 2023	$	2,319	$	298

Changes in the fair value of our Level 3 financial instruments for the three months ended March 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		18			57		12
Reclassification from liability to equity		(305	)		—		—
Balance – March 31, 2022	$	187		$	18,157	$	2,329

Valuation of Notes Payable and Convertible Notes Payable

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 (see Note 8), which approximates fair value. The 2021 Avenue Loan, 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. Our notes payable and convertible notes payable are categorized within Level 3 of the fair value hierarchy.

Valuation of the Common Stock Warrant Liability

The Avenue Warrant, comprised of the Tranche 1 warrant and the contingently issuable Tranche 2 warrant to purchase shares of Common Stock, were classified as liabilities and recorded at fair value at inception of the 2021 Avenue Loan. As of March 31, 2022, the exercise price and quantity of shares for 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 condensed consolidated statements of operations and comprehensive loss and the Tranche 1 warrant liability was reclassified to additional paid-in capital. Our ability to draw Tranche 2 expired on December 31, 2022 and the Tranche 2 warrant liability was extinguished and we recognized income of $0.2 million as of December 31, 2022.

Valuation of the Contingent Earn-Out Liabilities

The Contingent Earn-outs are carried at fair value, 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:

	*March 31,*			*December 31,*
	*2023*			*2022*
Expected stock price volatility		115.00	%		115.00	%
Risk-free interest rate		3.90	%		4.20	%
Expected dividend yield		0.00	%		0.00	%
Expected term (in years)		2.75			3.00

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 - Related Party Transactions (Tables)

3 Months Ended

Mar. 31, 2023

	*Three Months Ended March 31,*
(in thousands)	*2023*		*2022*
Product revenue from related parties	$	63	$	—
Royalty revenue from related parties		43		23
Total revenue from related parties	$	106	$	23

Note 14 - Net Loss Per Share Attributable to Common Stockholders - Antidilutive Securities Excluded from Computation (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Antidilutive securities (in shares)	29,819,656	24,411,747
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)	16,205,404	11,944,789
Restricted Stock [Member]
Antidilutive securities (in shares)	812,170	914,876
Contingent Earnout Shares [Member]
Antidilutive securities (in shares)	6,592,334	6,592,334

Note 3 - Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2023