Galectin Therapeutics (GALT) 10-K 30 Mar 23 2022 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Feb. 28, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Document Transition Report	false
Entity File Number	001-31791
Entity Registrant Name	GALECTIN THERAPEUTICS INC.
Entity Central Index Key	0001133416
Entity Incorporation, State or Country Code	NV
Entity Tax Identification Number	04-3562325
Entity Address, Address Line One	4960 Peachtree Industrial Blvd
Entity Address, Address Line Two	Suite 240
Entity Address, City or Town	Norcross
Entity Address, State or Province	GA
Entity Address, Postal Zip Code	30071
City Area Code	678
Local Phone Number	620-3186
Title of 12(b) Security	Common Stock, $0.001 Par Value Per Share
Trading Symbol	GALT
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 59
Entity Common Stock, Shares Outstanding		59,443,682
Auditor Firm ID	677
Auditor Name	CHERRY BEKAERT LLP
Auditor Location	Atlanta, Georgia

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 18,592,000	$ 39,648,000
Prepaid expenses and other current assets	1,960,000	2,172,000
Total current assets	20,552,000	41,820,000
Property and equipment, net	0	0
Other	733,000	7,000
Total assets	21,285,000	41,827,000
Current liabilities:
Accounts payable	3,890,000	1,805,000
Accrued expenses	9,058,000	7,163,000
Accrued dividends payable	64,000	65,000
Total current liabilities	13,012,000	9,033,000
Convertible note payable and accrued interest, net of debt discount - related party (Note 5)	29,964,000	29,048,000
Derivative liabilities (Note 6)	573,000	1,130,000
Borrowing and accrued interest under convertible line of credit, net of debt discount - related party (Note 10)	9,864,000	0
Other liabilities	66,000	0
Total liabilities	53,479,000	39,211,000
Commitments and contingencies (Note 12)
Series C 6% super dividend redeemable convertible preferred stock; 1,000 shares authorized, 176 issued and outstanding at December 31, 2022 and 2021, redemption value: $8,335,000, liquidation value: $1,786,000 at December 31, 2022	1,723,000	1,723,000
Stockholders' equity (deficit):
Undesignated stock, $0.01 par value; 20,000,000 shares authorized at December 31, 2022 and 2021, 20,000,000 shares designated at December 31, 2022 and 2021, respectively	0	0
Series A 12% convertible preferred stock; 1,742,500 shares authorized, 1,260,000 and 1,302,500 issued and outstanding at December 31, 2022 and 2021, respectively, liquidation value $1,260,000 at December 31, 2022	510,000	527,000
Common stock, $0.001 par value; 150,000,000 shares authorized at December 31, 2022 and 2021, 59,426,005 and 59,341,305 issued and outstanding at December 31, 2022 and 2021, respectively	59,000	59,000
Additional paid-in capital	275,081,000	271,001,000
Retained deficit	(309,567,000)	(270,694,000)
Total stockholders' equity (deficit)	(33,917,000)	893,000
Total liabilities, redeemable convertible preferred stock and stockholders' equity (deficit)	$ 21,285,000	$ 41,827,000

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
LIABILITIES, REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT)
Series C 6% super dividend redeemable convertible preferred stock, shares authorized (in shares)	1,000	1,000
Series C 6% super dividend redeemable convertible preferred stock, shares issued (in shares)	176	176
Series C 6% super dividend redeemable convertible preferred stock, shares outstanding (in shares)	176	176
Series C 6% super dividend redeemable convertible preferred stock, redemption value	$ 8,335,000
Series C 6% super dividend redeemable convertible preferred stock liquidation value	$ 1,786,000
Stockholders' equity (deficit):
Undesignated stock, par value (in dollars per share)	$ 0.01	$ 0.01
Undesignated stock, shares authorized (in shares)	20,000,000	20,000,000
Undesignated stock, shares designated (in shares)	20,000,000	20,000,000
Series A 12% convertible preferred stock, shares authorized (in shares)	1,742,500	1,742,500
Series A 12% convertible preferred stock, shares issued (in shares)	1,260,000	1,302,500
Series A 12% convertible preferred stock, shares outstanding (in shares)	1,260,000	1,302,500
Series A 12% convertible preferred stock, liquidation value	$ 1,260,000,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, issued (in shares)	59,426,005	59,341,305
Common stock, outstanding (in shares)	59,426,005	59,341,305

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating expenses:
Research and development	$ 31,737	$ 23,818
General and administrative	6,615	6,361
Total operating expenses	38,352	30,179
Total operating loss	(38,352)	(30,179)
Other income (expense):
Interest income	52	3
Interest expense	(1,033)	(489)
Change in fair value of derivatives	557	138
Total other income (expense)	(424)	(348)
Net loss	(38,776)	(30,527)
Preferred stock dividends	(97)	(171)
Net loss applicable to common stockholders	$ (38,873)	$ (30,698)
Net loss per common share - basic (in dollars per share)	$ (0.65)	$ (0.52)
Net loss per common share - diluted (in dollars per share)	$ (0.65)	$ (0.52)
Weighted average common and potential common shares outstanding - basic (in shares)	59,391	58,527
Weighted average common and potential common shares outstanding - diluted (in shares)	59,391	58,527

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Preferred Stock [Member] Series A 12% Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Deficit [Member]	Total
Beginning balance at Dec. 31, 2020					$ 1,723
Beginning balance (in shares) at Dec. 31, 2020					176
Ending balance at Dec. 31, 2021					$ 1,723
Ending balance (in shares) at Dec. 31, 2021					176
Beginning balance at Dec. 31, 2020	$ 527	$ 56	$ 261,883	$ (239,996)	$ 22,470
Beginning balance (in shares) at Dec. 31, 2020	1,302,500	57,077,055
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Series A 12% convertible preferred stock dividend			79	(79)
Series A 12% convertible preferred stock dividend (in shares)		26,050
Series C super dividend redeemable convertible preferred stock dividend			92	(92)
Series C super dividend redeemable convertible preferred stock dividend (in shares)		31,112
Issuance of common stock		$ 1	3,863		3,864
Issuance of common stock for exercise of options (in shares)		845,214
Issuance of common stock for warrant exercises		$ 2	2,948		$ 2,950
Issuance of common stock for warrant exercises (in shares)		1,180,240
Issuance of common stock for stock option exercises (in shares)		148,941			148,941
Stock-based compensation expense			2,136		$ 2,136
Stock-based compensation expense (in shares)		32,693
Net loss				(30,527)	(30,527)
Ending balance at Dec. 31, 2021	$ 527	$ 59	271,001	(270,694)	893
Ending balance (in shares) at Dec. 31, 2021	1,302,500	59,341,305
Ending balance at Dec. 31, 2022					$ 1,723
Ending balance (in shares) at Dec. 31, 2022					176
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Series A 12% convertible preferred stock dividend			40	(40)
Series A 12% convertible preferred stock dividend (in shares)		25,625
Series C super dividend redeemable convertible preferred stock dividend			57	(57)
Series C super dividend redeemable convertible preferred stock dividend (in shares)		35,200
Issuance of common stock from conversion of Series A convertible preferred stock	$ (17)		17
Issuance of common stock from conversion of Series A convertible preferred stock (in shares)	(42,500)	7,287
Issuance of common stock for stock option exercises (in shares)					0
Issuance of common stock purchase warrants in connection with related party line of credit			899		$ 899
Stock-based compensation expense			3,067		3,067
Stock-based compensation expense (in shares)		16,588
Net loss				(38,776)	(38,776)
Ending balance at Dec. 31, 2022	$ 510	$ 59	$ 275,081	$ (309,567)	$ (33,917)
Ending balance (in shares) at Dec. 31, 2022	1,260,000	59,426,005

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (38,776)	$ (30,527)
Adjustments to reconcile net loss to net cash flows from operating activities:
Amortization of right to use asset	32	41
Stock-based compensation expense	2,867	2,076
Non-cash interest expense	410	283
Change in fair value of derivative	(557)	(138)
Changes in operating assets and liabilities:
Prepaid expenses and other assets	101	65
Accrued interest on convertible notes payable and convertible line of credit - related party	623	206
Accounts payable, accrued expenses and other liabilities	4,244	3,686
Net cash flows from operating activities	(31,056)	(24,308)
CASH FLOWS FROM INVESTING ACTIVITIES:
Net cash from investing activities	0	0
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from convertible line of credit - related party	10,000	0
Net proceeds from convertible note payable - related party	0	30,000
Net proceeds from issuance of common stock	0	6,814
Net cash flows from financing activities	10,000	36,814
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(21,056)	12,506
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	39,648	27,142
CASH AND CASH EQUIVALENTS, END OF PERIOD	18,592	39,648
NONCASH FINANCING ACTIVITIES:
Payment of preferred stock dividends in common stock	97	171
Fair value of derivative related to related party convertible note payable	0	1,268
Reclassification of accrued bonus to additional paid in capital	200	60
Noncash right to use lease asset	111	0
Common stock purchase warrants issued in connection with related party line of credit	$ 899	$ 0

Nature of Business, Basis of Pr

Nature of Business, Basis of Presentation and Liquidity	12 Months Ended
	Dec. 31, 2022
Nature of Business, Basis of Presentation and Liquidity [Abstract]
Nature of Business, Basis of Presentation and Liquidity	1. Nature of Business, Basis of Presentation and Liquidity Galectin Therapeutics Inc. and subsidiaries (the “Company”) is a clinical stage biopharmaceutical company that is applying its leadership in galectin science and drug development to create new therapies for fibrotic disease and cancer. These candidates are based on the Company’s targeting of galectin proteins which are key mediators of biologic and pathologic function. These compounds also may have application for drugs to treat other diseases and chronic health conditions. The Company was founded in July 2000, was incorporated in the State of Nevada in January 2001 under the name “Pro-Pharmaceuticals, Inc.,” and changed its name to “Galectin Therapeutics Inc.” on May 26, 2011. The Company has operated at a loss since its inception and has had no revenues. The Company anticipates that losses will continue for the foreseeable future. At December 31, 2022, the company had $18,592,000 of unrestricted cash and cash equivalents available to fund future operations. In July 2022, the Company entered into a $60 million unsecured line of credit financing with its chairman, Richard E. Uihlein (See Note 10). The Company believes there is sufficient cash, including availability of the line of credit, to fund currently planned operations at least through December 31, 2024. To meet its future capital needs, the Company intends to raise additional capital through debt or equity financings, collaborations, partnerships or other strategic transactions. However, there can be no assurance that the Company will be able to complete any such transactions on acceptable terms or otherwise. The inability of the Company to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on the Company’s business, results of operations and financial condition. The Company has the ability to delay certain research activities and related clinical expenses if necessary due to liquidity concerns until a date when those concerns are relieved. The Company is subject to a number of risks similar to those of clinical stage companies, including dependence on key individuals, uncertainty of product development and generation of revenues, dependence on outside sources of capital, risks associated with clinical trials of products, dependence on third-party collaborators for research operations, need for regulatory approval of products, risks associated with protection of intellectual property, and competition with larger, better-capitalized companies. Successful completion of the Company’s development program and, ultimately, the attainment of profitable operations is dependent upon future events, including obtaining adequate financing to fulfill its development activities and achieving a level of revenues adequate to support the Company’s cost structure. There are no assurances that the Company will be able to obtain additional financing on favorable terms, or at all, or successfully market its products.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2022
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (“GAAP”). Basis of Consolidation. The consolidated financial statements include the accounts of the Company and Galectin Therapeutics Security Corp., its wholly-owned subsidiary, which was incorporated in Delaware on December 23, 2003 and Galectin Sciences LLC (see Note 13). All intercompany transactions have been eliminated. Use of Estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and judgments that may affect the reported amounts of assets, liabilities, equity, revenue, expenses and related disclosure of contingent assets and liabilities. Management’s estimates and judgments include assumptions used in stock option valuations, useful lives of property and equipment and intangible assets, accrued liabilities, derivative valuations, deferred income taxes and various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from those estimates under different assumptions or conditions. Fair Value Measurements . The Company has certain financial assets and liabilities recorded at fair value. Fair values determined by Level 1 inputs utilize observable data such as quoted prices in active markets. Fair values determined by Level 2 inputs utilize data points other than quoted prices in active markets that are observable either directly or indirectly. Fair values determined by Level 3 inputs utilize unobservable data points in which there is little or no market data, which require the reporting entity to develop its own assumptions. The estimated value of accounts payable and accrued expenses approximates their carrying value due to their short-term nature. See Cash and Cash Equivalents. The Company considers all highly-liquid investments with original maturities of 90 days or less at the time of acquisition to be cash equivalents. The Company had no cash equivalents at December 31, 2022 or 2021. Prepaid Expenses and Other Current Assets. Prepaid expenses and other assets consist principally of prepaid insurance, deposits related to the NAVIGATE trial and deferred financing costs (see Note 10). Property and Equipment. Property and equipment, including leasehold improvements, are stated at cost, net of accumulated depreciation and amortization, and are depreciated or amortized using the straight-line method over the estimated useful lives of the related assets of generally three years for computers and office equipment, five years for furniture and fixtures and the shorter of the useful life or life of the lease for leasehold improvements. Security Deposit. At December 31, 2022 and 2021, the Company had a security deposit of $6,000 for leased office space included in Prepaid Expenses and Other Current Assets. Long-Lived Assets. The Company reviews all long-lived assets for impairment whenever events or circumstances indicate the carrying amount of such assets may not be recoverable. Recoverability of assets to be held or used is measured by comparison of the carrying value of the asset to the future undiscounted net cash flows expected to be generated by the asset. If such asset is considered to be impaired, the impairment recognized is measured by the amount by which the carrying value of the asset exceeds the discounted future cash flows expected to be generated by the asset. There were no impairments of long-lived assets at December 31, 2022 or 2021. Accrued Expenses . As part of the process of preparing our consolidated financial statements, we are required to estimate accrued expenses. This process involves identifying services that third parties have performed on our behalf and estimating the level of service performed and the associated cost incurred on these services as of each balance sheet date in our consolidated financial statements. Examples of estimated accrued expenses include professional service fees, such as those arising from the services of attorneys and accountants and accrued payroll expenses. In connection with these service fees, our estimates are most affected by our understanding of the status and timing of services provided relative to the actual services incurred by the service providers. In the event that we do not identify certain costs that have been incurred or we under- or over-estimate the level of services or costs of such services, our reported expenses for a reporting period could be understated or overstated. The date on which certain services commence, the level of services performed on or before a given date, and the cost of services are often subject to our judgment. We make these judgments based upon the facts and circumstances known to us in accordance with accounting principles generally accepted in the U.S. Warrants. The Company has issued common stock warrants in connection with the execution of certain equity and debt financings. The fair value of warrants is determined using the Black-Scholes option-pricing model using assumptions regarding volatility of our common share price, remaining life of the warrant, and risk-free interest rates at each period end. There were no warrant liabilities as of December 31, 2022 or 2021. Research and Development Expenses. Research and development expenses, including personnel costs, allocated facility costs, lab supplies, outside services, contract laboratory costs related to manufacturing drug product, clinical trials and preclinical studies are charged to research and development expense as incurred. The Company accounts for nonrefundable advance payments for goods and services that will be used in future research and development activities as expense when the service has been performed or when the goods have been received. Our current NAVIGATE clinical trial is being supported by third-party contract research organizations, or CROs, and other vendors. We accrue expenses for clinical trial activities performed by CROs based upon the estimated amount of work completed on each trial. For clinical trial expenses and related expenses associated with the conduct of clinical trials, the significant factors used in estimating accruals include the number of patients enrolled, the number of active clinical sites, and the duration for which the patients have been enrolled in the trial. We monitor patient enrollment levels and related activities to the extent possible through internal reviews, review of contractual terms and correspondence with CROs. We base our estimates on the best information available at the time. We monitor patient enrollment levels and related activities to the extent possible through discussions with CRO personnel and based our estimates of clinical trial costs on the best information available at the time. However, additional information may become available to us which will allow us to make a more accurate estimate in future periods. In that event, we may be required to record adjustments to research and development expenses in future periods when the actual level of activity becomes more certain. Income Taxes. The Company accounts for income taxes in accordance with the accounting rules that requires an asset and liability approach to accounting for income taxes based upon the future expected values of the related assets and liabilities. Deferred income tax assets and liabilities are determined based on the differences between the financial reporting and tax bases of assets and liabilities and for tax loss and credit carry forwards and are measured using the expected tax rates estimated to be in effect when such basis differences reverse. Valuation allowances are established, if necessary, to reduce the deferred tax asset to the amount that will, more likely than not, be realized. Concentration of Credit Risk. Financial instruments that subject the Company to credit risk consist of cash and cash equivalents. The Company maintains cash and cash equivalents and certificates of deposit with well-capitalized financial institutions. At times, those amounts may exceed federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant credit risk beyond the normal credit risk associated with commercial banking relationships. The Company has no other significant concentrations of credit risk. Stock-Based Compensation. Stock-based compensation cost is measured at the grant date based on the fair value of the award and is recognized as expense over the service period, which generally represents the vesting period. For awards that have performance-based vesting conditions the Company recognizes the expense over the estimated period that the awards are expected to be earned. The Company generally uses the Black-Scholes option-pricing model to calculate the grant date fair value of stock options. The expense recognized over the service period is required to include an estimate of the awards that will be forfeited. Recent Accounting Standards.

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2022
Property and Equipment [Abstract]
Property and Equipment	3. Property and Equipment Property and equipment consist of the following at December 31: 2022 2021 (in thousands) Leasehold improvements $ 2 $ 2 Computer and office equipment 13 13 Furniture and fixtures 59 59 Total 74 74 Less accumulated depreciation and amortization (74 ) (74 ) Property and equipment — net $ — $ — Depreciation and amortization expense for the years ended December 31, 2022 and 2021 was $0 and $0, respectively.

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2022
Accrued Expenses [Abstract]
Accrued Expenses	4. Accrued Expenses Accrued expenses consist of the following at December 31: 2022 2021 (in thousands) Legal and accounting fees $ 65 $ 68 Accrued compensation 973 728 Lease liability 40 8 Accrued research and development costs and other 7,980 6,359 Total $ 9,058 $ 7,163

Convertible Notes Payable - Rel

Convertible Notes Payable - Related Party	12 Months Ended
	Dec. 31, 2022
Convertible Notes Payable - Related Party [Member]
Debt Instrument [Line Items]
Convertible Notes Payable - Related Party	5. Convertible Notes Payable – Related Party On April 16, 2021, the Company and Richard E. Uihlein entered into a debt financing arrangement whereby Mr. Uihlein loaned $10,000,000 to Company. In consideration for the loan, the Company issued a convertible promissory note (the “April 2021 Note”) in the principal amount of ten million dollars. The April 2021 Note has a maturity date of April 16, 2025, is prepayable at the option of the Company in whole or in part at any time and is convertible into the Company’s common stock at a conversion price equal to $5.00 per share at the option of the noteholder. The April 2021 Note bears interest at the rate of two percent (2%) per annum, compounded annually with an effective interest rate of approximately 3%. For the years ended December 31, 2022 and 2021, approximately $200,000 and $142,000, respectively, of interest expense was accrued and included with the principal in the financial statements. The April 2021 Note also includes a contingent interest component that requires the Company to pay additional interest at a rate of two and one-half percent (2.5%) per quarter (10% per annum) (the “Additional Interest”) beginning on the date of issuance of this Note and ending on the maturity date, provided however, that such payment is only required if and only if the noteholder elects to convert the entire balance of the April 2021 Note into the Company’s common stock on or prior to maturity. As the contingent event is not based on creditworthiness, such feature is not clearly and closely related to the host instrument and accordingly must be bifurcated and recognized as a derivative liability and a debt discount on the April 2021 Note at its inception. The fair value of the contingent interest derivative liability was $420,000 at note inception (April 16, 2021). The fair value of the contingent interest derivative liability was $249,000 and $495,000 and December 31, 2022 and 2021, respectively, and is recognized as a derivative liability in the consolidated balance sheet. The change in the fair value of the derivative liability from April 16, 2021 to December 31, 2021 and for the year ended December 31, 2022 of $75,000 and $(246,000), respectively, was charged to other expense/(income) for the years ended December 31, 2022 and 2021. The amortization of the original $420,000 debt discount of $105,000 and $74,000 was recorded as additional interest expense for the years ended December 31, 2022 and 2021, respectively. On September 17, 2021, the Company and Mr. Uihlein entered into a loan agreement in the aggregate of $20,000,000 (the “Loan Agreement”) to be funded in two closings and evidenced by two separate unsecured convertible promissory notes. The first of the two promissory notes was also executed and delivered on September 17, 2021, (the “September 2021 Note”) to evidence the first loan in the principal amount of $10,000,000. The second closing under the Loan Agreement for the remaining $10,000,000 occurred on December 20, 2021. The September 2021 Note has a maturity date of September 17, 2025, is prepayable at the option of the Company in whole or in part at any time and is convertible into the Company’s common stock at a conversion price equal to $8.64 per share at the option of the noteholder. The September 2021 Note bears interest at the rate of two percent (2%) per annum, compounded annually with an effective interest rate of approximately 3%. For the years ended December 31, 2022 and 2021, approximately $200,000 and $58,000, respectively, of interest expense was accrued and included with the principal in the financial statements. The September 2021 Note also includes a contingent interest component that requires the Company to pay additional interest at a rate of two and one-half percent (2.5%) per quarter (10% per annum) (the “Additional Interest”) beginning on the date of issuance of this Note and ending on the maturity date, provided however, that such payment is only required if and only if the noteholder elects to convert the entire balance of the September 2021 Note into the Company’s common stock on or prior to maturity. As the contingent event is not based on creditworthiness, such feature is not clearly and closely related to the host instrument and accordingly must be bifurcated and recognized as a derivative liability and a debt discount on the September Note at its inception. The fair value of the contingent interest derivative liability was $433,000 at note inception (September 17, 2021). The fair value of the contingent interest derivative liability was $109,000 and $250,000 and December 31, 2022 and 2021, respectively, and is recognized as a derivative liability in the consolidated balance sheet. The change in the fair value of the derivative liability from September 17, 2021 to December 31, 2021 and for the year ended December 31, 2022 of ($183,000) and ($141,000), respectively, was recorded to other expense/(income) for the years ended December 31, 2021 and 2022. The amortization of the original $433,000 debt discount of $108,000 and $32,000 was recorded as additional interest expense for the years ended December 31, 2022 and 2021, respectively. On December 20, 2021, the second of the two promissory notes under the Loan Agreement was executed and delivered, (the “December 2021 Note”) to evidence the second loan in the principal amount of $10,000,000. The December 2021 Note has a maturity date of December 20, 2025, is prepayable at the option of the Company in whole or in part at any time and is convertible into the Company’s common stock at a conversion price equal to $5.43 per share at the option of the noteholder. The December Note bears interest at the rate of two percent (2%) per annum, compounded annually with an effective interest rate of approximately 3%. For the year ended December 31, 2022 and 2021, approximately $200,000 and $7,000, respectively, of interest expense was accrued and included with the principal in the financial statements. The December 2021 Note also includes a contingent interest component that requires the Company to pay additional interest at a rate of two and one-half percent (2.5%) per quarter (10% per annum) (the “Additional Interest”) beginning on the date of issuance of this Note and ending on the maturity date, provided however, that such payment is only required if and only if the noteholder elects to convert the entire balance of the December 2021 Note into the Company’s common stock on or prior to maturity. As the contingent event is not based on creditworthiness, such feature is not clearly and closely related to the host instrument and accordingly must be bifurcated and recognized as a derivative liability and a debt discount on the December Note at its inception. The fair value of the contingent interest derivative liability was $415,000 at note inception (December 20, 2021). The fair value of the contingent interest derivative liability was $214,000 and $385,000 at December 31, 2022 and 2021, respectively, and is recognized as a derivative liability in the consolidated balance sheet. The change in the fair value of the derivative liability from December 20, 2021 to December 31, 2021 and for the year ended December 31, 2022 of ($30,000) and ($170,000), respectively was recorded to other expense/(income) for the years ended December 31, 2022 and 2021. The amortization of the original $415,000 debt discount of $104,000 and $3,000 was recorded as additional interest expense for the years ended December 31, 2022 and 2021, respectively. The Company’s contractual cash obligations related to the outstanding convertible notes payable is a repayment of the April 2021 Note of the $10,000,000 plus accrued interest on April 16, 2025 and a repayment of the September 2021 Note of the $10,000,000 plus accrued interest on September 17, 2025 and a repayment of the December 2021 Note of the $10,000,000 plus accrued interest on December 30, 2025, unless converted at the option of the noteholder.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2022
Fair Value of Financial Instruments [Abstract]
Fair Value of Financial Instruments	6. Fair Value of Financial Instruments There were no level 1 or 2 assets or liabilities at December 31, 2022 or 2021. Level 3 assets and liabilities measured and recorded at fair value on a recurring basis at December 31, 2022 and 2021 were as follows: December 31, 2022 December 31, 2021 Derivative Liability – Contingent Interest April Note $ 249,000 $ 495,000 Derivative Liability – Contingent Interest September Note $ 109,000 $ 250,000 Derivative Liability – Contingent Interest December Note $ 215,000 $ 385,000 The April 2021 Note derivative liability – contingent interest was valued using a Monte Carlo Geometric Brownian Stock Path Model. The key assumptions used in the model at December 31, 2022 and 2021 are as follows: December 31, 2022 December 31, 2021 Stock Price $ 1.13 $ 2.07 Conversion Price of conversion feature $ 5.00 $ 5.00 Term 2.29 3.29 years Risk Free Interest Rate 4.41 % 0.97 % Credit Adjusted Discount Rate 14.76 % 8.43 % Volatility 81 % 80 % Dividend Rate 0 % 0 % The roll forward of the April 2021 Note derivative liability – contingent interest is as follows: Balance – December 31, 2020 $ — Issuance of April convertible note payable – related party 420,000 Fair Value Adjustment 75,000 Balance – December 31, 2021 495,000 Fair Value Adjustment (246,000 ) Balance – December 31, 2022 $ 249,000 The September 2021 Note derivative liability – contingent interest was valued using a Monte Carlo Geometric Brownian Stock Path Model. The key assumptions used in the model at inception, and at December 31, 2022 and 2021 are as follows: December 31, 2022 December 31, 2021 Stock Price $ 1.13 $ 2.07 Conversion Price of conversion feature $ 8.64 $ 8.64 Term 2.72 years 3.72 years Risk Free Interest Rate 4.22 % 1.12 % Credit Adjusted Discount Rate 14.76 % 8.42 % Volatility 81 % 82 % Dividend Rate 0 % 0 % The roll forward of the September 2021 Note derivative liability – contingent interest is as follows: Balance – December 31, 2020 $ — Issuance of September convertible note payable – related party 433,000 Fair Value Adjustment (183,000 ) Balance – December 31, 2021 250,000 Fair Value Adjustment (141,000 ) Balance – December 31, 2022 $ 109,000 The December 2021 Note derivative liability – contingent interest was valued using a Monte Carlo Geometric Brownian Stock Path Model. The key assumptions used in the model at inception, and at December 31, 2022 and 2021 are as follows: December 31, 2022 December 31, 2021 Stock Price $ 1.13 $ 2.07 Conversion Price of conversion feature $ 5.43 $ 5.43 Term 2.97 3.97 Risk Free Interest Rate 4.22 % 1.12 % Credit Adjusted Discount Rate 14.76 % 8.42 % Volatility 83 % 84 % Dividend Rate 0 % 0 % The roll forward of the December 2021 Note derivative liability – contingent interest is as follows: Balance – December 31, 2020 $ — Issuance of September convertible note payable – related party 415,000 Fair Value Adjustment (30,000 ) Balance – December 31, 2021 385,000 Fair Value Adjustment (170,000 ) Balance – December 31, 2022 $ 215,000

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2022
Stockholders' Equity [Abstract]
Stockholders' Equity	7. Stockholders’ Equity At December 31, 2022, the Company had 150,000,000 shares of common stock and 20,000,000 undesignated shares authorized. As of December 31, 2022, 1,742,500 shares have been designated for Series A 12% Convertible Preferred Stock, 900,000 shares have been designated for Series B-1 Convertible Preferred Stock, 2,100,000 shares have been designated for Series B-2 Convertible Preferred Stock, 1,000 shares have been designated for Series C Super Dividend Convertible Preferred Stock, 2,508,000 shares have been designated for Series B-3 Convertible Preferred Stock, 12,748,500 have been designated as common stock and no shares remain undesignated. All issued and outstanding shares of Series B-1, Series B-2 and Series B-3 Preferred Stock were converted into Common Stock on January 19, 2019. 2020 At Market Issuance of Common Stock On May 11, 2020, the Company entered into an At Market Issuance Sales Agreement (the “2020 At Market Agreement”) with a sales agent under which the Company may issue and sell shares of its common stock having an aggregate offering price of up to $40.0 million from time to time through the sales agent. Sales of the Company’s common stock through the sales agent, if any, will be made by any method that is deemed an “at the market” offering as defined by the U.S. Securities and Exchange Commission. The Company will pay to the sales agent a commission rate equal to 3.0% of the gross proceeds from the sale of any shares of common stock sold through the sales agent under the 2020 At Market Agreement. During the year ended December 31, 2021, the Company issued 845,214 shares of common stock under the 2020 At Market Agreement for net proceeds of $3,864,000. There were no issuances of common stock under the 2020 At Market Agreement during the year ended December 31, 2022. Series A 12% Convertible Preferred Stock — February 4, 2008 Private Placement On February 4, 2008, the Company closed a private placement begun in October 2007 of its Series A 12% Convertible Preferred Stock (“Series A”) and related warrants. In this transaction, the Company sold units of securities at $6.00 per unit, each unit comprised of (i) one share of Series A Preferred, (ii) a warrant to purchase one share of common stock for $9.00, and (iii) a warrant to purchase one share of common stock for $12.00. Each share of the Series A is entitled to dividends at the rate of 12% per annum payable at the Company’s option in cash or shares of common stock valued at the higher of $6.00 per share or 100% of the value weighted average price of the Company’s share price for the 20 consecutive trading days prior to the applicable dividend payment date. Dividends are payable semi-annually on March 30 and September 30. The dividend paid on the initial dividend payment date is calculated from the date the Company deposited each subscription advance. The shares of Series A are entitled to vote as a class with the Company’s common stock and each share of Series A is convertible at any time to one-sixth of a share of common stock, subject to adjustment in the event of a stock dividend, stock split or combination, reclassification or similar event. The Company has the right to require conversion if the closing price of the common stock exceeds $18.00 for 15 consecutive trading days and a registration statement covering the resale of the shares of common stock issuable upon conversion of the Series A is then in effect. Each warrant is exercisable solely for cash beginning August 3, 2008 and expired on February 4, 2012. The exercise price of each warrant is adjustable in the event of a stock split or stock combination, capital reorganization, merger or similar event. In 2022, 42,500 shares of Series A were converted into 7,287 shares of common stock. There were no shares of Series A converted into shares of common stock in 2021. Prior to 2021, a total of 465,000 shares of Series A had been converted into 73,865 shares of common stock. Series C 6% Super Dividend Redeemable Convertible Preferred Stock On December 29, 2010, the Company designated and authorized the sale and issuance of up to 1,000 shares of Series C Super Dividend Redeemable Convertible Preferred Stock (“Series C”) with a par value of $0.01 and a stated value equal to $10,000 (the “Stated Value”). On December 30, 2010, the Company sold and issued 212 shares of Series C at a price of $10,000 per share for gross proceeds of $2,120,000. The Company incurred $47,000 of cash transaction costs resulting in net cash proceeds of $2,073,000. In addition, the Company issued 500 warrants exercisable at $7.20 to a placement agent which had a de minimis value. Additionally, in January 2011, the Company sold and issued 13 shares of Series C at a price of $10,000 per share for gross proceeds of $130,000. The terms of the Series C are as follows: Conversion Rights . Each holder of Series C may convert all, but not less than all, of his Series C shares plus accrued and unpaid dividends into Common Stock at the price of $6.00 per share of Common Stock (“Conversion Price”), such that approximately 1,667 shares of Common Stock will be issued per each converted share of Series C (accrued and unpaid dividends will be issued as additional shares). At December 31, 2018 and 2017, the 176 outstanding shares of Series C were convertible into a total of approximately 293,340 shares of Common Stock. Subject to the continuing obligation to pay post conversion dividends, the Company may convert all, but not less than all, of the Series C (plus all accrued and unpaid dividends) into Common Stock, at the Conversion Price, upon such time that the closing price of the Common Stock is no less than $18.00 per share for 15 consecutive trading days. Dividends . Holders of Series C shall be entitled to receive cumulative non-compounding dividends at the rate per share of Series C equal to the greater of (i) 6% per annum of the Stated Value (also defined as the “Floor”) or (ii) 2.5% of net sales until the total dividends paid is equal to the initial investment and 1.25% of net sales thereafter. The maximum amount each Series C shareholder will receive in dividend payments is equal to $100,000 (the “Maximum Payout”). For purposes of this dividend calculation, net sales shall mean gross revenues actually received by the Company, from the sale or licensing of the product DAVANAT ® The dividend shall be payable in arrears semiannually on March 31 and September 30, beginning with the first such date after the original issue date; provided, however, that all dividends and all other distributions shall cease, and no further dividends or other distributions shall be paid, in respect of each share of Series C from and after such time that the Maximum Payout has been paid in respect of such share of Series C. Such dividends shall be payable at the Company’s option either in cash or in duly authorized, fully paid and non-assessable shares of Common Stock valued at the higher of (i) $3.00 per share or (ii) the average of the Common Stock trading price for the ten (10) consecutive trading days ending on the trading day that is immediately prior to the dividend payment date. Series C Post Conversion Dividend Right . In the event that any share of Series C is converted into Common Stock before the Maximum Payout is paid in respect of such converted share of Series C, then the holder shall have the right to continue to receive dividends in respect of such converted share of Series C equal to the remaining payout (the “Series C Preferred Stock Post Conversion Dividend Right”) which shall be equal to the Maximum Payout less the cumulative dividends received through the conversion date. One share of Series C Preferred Stock Post Conversion Dividend Right shall be issued for each such converted share of Series C. The holder of each Series C Preferred Stock Post Conversion Dividend Right shall receive the remaining payout on an equal basis and in conjunction with the then outstanding shares of Series C and all the other then outstanding Series C Post Conversion Dividend Rights, in the same manner and subject to the same terms and conditions as applicable to the payment of dividends on each share of Series C, except that for purposes of calculating the dividend the Floor shall not apply. The Series C Preferred Stock Post Conversion Dividend Right shall have no stated value, liquidation preference or right to any dividends or distributions other than the remaining payout. The Series C Preferred Stock Post Conversion Right is subject to redemption in the same manner as outstanding Series C shares. At the date of issuance, the Series C have an embedded dividend right to continue to receive dividend payments after conversion to common stock (the Series C Post Conversion Dividend Right) which requires bifurcation. The value of this post conversion dividend right on the date of issuance was determined to be de minimis due to the fact that the payment of a dividend stream other than the 6% dividend and conversion of Series C prior to the Company achieving sales of GM-CT-01 was deemed improbable at that time. Upon a conversion of the Series C, the Company will be required to record a liability and the related expense during the period of conversion. In July 2011, 5 shares of Series C were converted into 8,334 shares of common stock and 5 Series C Post Conversion Dividend Rights (Dividend Rights) were issued. In 2013, 24 shares of Series C were converted into 40,193 shares of common stock and 24 Dividend Rights were issued. In 2014, 20 shares of Series C were converted into 33,756 shares of common stock and 20 Dividend Rights were issued. Per the terms of the Series C, these Dividend Rights shall continue to participate in dividends, however the Floor shall not apply. At December 31, 2016 and 2015, these Dividend Rights were determined to have a de minimis value, as the payment of a dividend is considered improbable at this time. The Company will continue to evaluate and assess the Series C Post Conversion Dividend Right for each reporting period. Liquidation Rights . In the event of any liquidation, dissolution or winding up of the Company, either voluntarily or involuntarily, the holders of Series C will receive $10,000 per share plus accrued and unpaid dividends, payable prior and in preference to any distributions to the holders of Common Stock but after and subordinate to the Series A 12% Convertible Preferred Stock (“Series A”), Series B-1 and Series B-2, subject to the Maximum Payout. Redemption . Upon a sale of the Company, the Company shall redeem all of the then outstanding shares of Series C and Series C Preferred Stock Post Conversion Rights within thirty (30) days after the transaction constituting the sale of the Company is closed and such closing is fully funded. The price to redeem a share of Series C and each redeemed Series C Preferred Stock Post Conversion Redemption Right shall be equal to (i) (A) the applicable return on investment (“ROI”) percentage, multiplied by (B) $10,000, minus (ii) the cumulative dividends received through the redemption date. The redemption price shall be payable at the Company’s option either in cash or in shares of common stock valued at the higher of (i) $3.00 per share or (ii) the average market price for the ten ROI Percentage 200% before the second anniversary of the date of issuance; 250% on or after the second anniversary of the date of issuance, but before the third anniversary of the date of issuance; 300 on or after the third anniversary of the date of issuance, but before the fourth anniversary of the date of issuance; 350 on or after the fourth anniversary of the date of issuance, but before the fifth anniversary of the date of issuance; 400 on or after the fifth anniversary of the date of issuance, but before the sixth anniversary of the date of issuance; 450 on or after the sixth anniversary of the date of issuance, but before the seventh anniversary of the date of issuance; 500 on or after the seventh anniversary of the date of issuance, but before the eighth anniversary of the date of issuance; and 550 on or after the eighth anniversary of the date of issuance, but before the ninth anniversary of the date of issuance. Due to the redemption feature, the Company has presented the Series C outside of permanent equity, in the mezzanine of the consolidated balance sheets at December 31, 2022 and 2021. At December 31, 2022, the Series C redemption value was $8,335,000. Voting Rights . The Series C shares have no voting rights.

Warrants

Warrants	12 Months Ended
	Dec. 31, 2022
Warrants [Abstract]
Warrants	8. Warrants Warrant activity is summarized as follows: Warrants Weighted average exercise price Outstanding at December 31, 2020 12,538,204 $ 4.22 Issued — Exercised (1,180,240 ) 2.50 Canceled (500,000 ) 5.00 Outstanding at December 31, 2021 10,857,964 $ 4.37 Issued 700,000 4.43 Exercised — Canceled — Outstanding at December 31, 2022 11,557,964 $ 4.37 The following table summarizes information with regard to outstanding warrants issued in connection with equity and debt financings and consultants as of December 31, 2022. Issued in Connection With Number Issued Exercise Price Exercisable Date Expiration Date February 12, 2009 3.00 1,200,000 $ 3.00 February 12, 2009 February 12, 2024 May 13, 2009 3.00 600,000 $ 3.00 May 13, 2009 May 13, 2024 June 30, 2009 3.00 333,333 $ 3.00 June 30, 2009 June 30, 2024 August 12, 2009 3.00 200,000 $ 3.00 August 12, 2009 August 12, 2024 September 30, 2009 3.00 216,666 $ 3.00 September 30, 2009 September 30, 2024 November 4, 2009 3.00 106,666 $ 3.00 November 4, 2009 November 4, 2024 December 8, 2009 3.00 133,143 $ 3.00 December 8, 2009 December 8, 2024 January 29, 2010 3.00 216,667 $ 3.00 January 29, 2010 January 29, 2025 March 8, 2010 3.00 223,334 $ 3.00 March 8, 2010 March 8, 2025 April 30, 2010 3.00 204,192 $ 3.00 April 30, 2010 April 30, 2025 May 10, 2010 3.00 143,166 $ 3.00 May 10, 2010 May 10, 2025 September 22, 2016 3.00 698,158 $ 3.00 September 22, 2016 September 22, 2023 September 29, 2016 3.00 846,100 $ 3.00 September 29, 2016 September 29, 2023 December 22, 2016 1,466,204 $ 5.00 December 22, 2016 December 23, 2023 December 23, 2016 3.00 924,780 $ 3.00 December 23, 2016 December 23, 2023 December 28, 2016 644,468 $ 5.00 December 28, 2016 December 28, 2023 February 27, 2017 76,776 $ 5.00 February 27, 2017 February 27, 2024 2018 and 2017 Warrants issued for services 2,157 $ 5.00 Various dates in 2018 and 2017 Various dates in 2025 and 2024 May 23, 2019 2,622,154 $ 7.00 May 23, 2019 May 23, 2026 July 22, 2022 500,000 $ 5.00 July 22, 2022 July 31, 2029 December 19, 2022 200,000 $ 3.00 December 19, 2022 July 31, 2029 Total outstanding warrants 11,557,964

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2022
Stock-Based Compensation [Abstract]
Stock-Based Compensation	9. Stock-Based Compensation Summary of Stock-Based Compensation Plans At December 31, 2022, the Company has a stock-based compensation plan where the Company’s common stock has been made available for equity-based incentive grants as part of the Company’s compensation programs. In December 2019, the Company adopted the 2019 Omnibus Equity Incentive Plan (the “2019 Plan”) which provided originally for the issuance of up to 4,000,000 shares of the Company’s common stock, subsequently increased to 7,000,000 in December 2021, in the form of options, stock appreciation rights, restricted stock and other stock-based awards to employees, officers, directors, consultants and other eligible persons. At December 31, 2022, 1,966,279 shares were available for future grant under the 2019 Plan. Also, the Company previously had the 2009 Incentive Compensation Plan (the “2009 Plan”) which, after amendments, provided for issuance of up to 6,733,334 shares of the Company’s common stock in the form of options, stock appreciation rights, restricted stock and other stock-based awards to employees, officers, directors, consultants and other eligible persons. Provisions of the 2009 Plan stipulated that no grants could be made after February 2019; however, grants made prior to that date remain outstanding for their legal term. Stock-Based Compensation Following is the stock-based compensation expense related to common stock options, restricted common stock, common stock warrants and deferred stock units: Year Ended December 31, 2022 2021 Research and development $ 810 $ 420 General and administrative 2,057 1,656 Total stock-based compensation expense $ 2,867 $ 2,076 The fair value of the options granted is determined using the Black-Scholes option-pricing model. The following weighted average assumptions were used: 2022 2021 Risk-free interest rate 1.85 % 0.66 % Expected life of the options 5.7 years 6.0 years Expected volatility of the underlying stock 93.7 % 91.7 % Expected dividend rate 0 % 0 % As noted above, the fair value of stock options is determined by using the Black-Scholes option pricing model. For all options granted since January 1, 2006 the Company has generally used option terms of between 5 to 10 years, generally with 5 to 6 years representing the estimated life of options granted to employees. The volatility of the common stock is estimated using historical volatility over a period equal to the expected life at the date of grant. The risk-free interest rate used in the Black-Scholes option pricing model is determined by reference to historical U.S. Treasury constant maturity rates with terms equal to the expected terms of the awards. An expected dividend yield of zero is used in the option valuation model, because the Company does not expect to pay any cash dividends on common stock in the foreseeable future. At December 31, 2022, the Company does not anticipate any option awards will be forfeited in the calculation of compensation expense due to the limited number of employees that receive stock option grants and the Company’s historical employee turnover; however, any forfeitures will be accounted for as incurred. The following table summarizes the stock option activity in the stock-based compensation plans: Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value (in thousands) Outstanding, December 31, 2020 3,987,575 $ 4.29 Granted 2,660,000 2.39 Forfeited/Cancelled (1,603,073 ) 5.31 Exercised (148,941 ) 2.35 Outstanding, December 31, 2021 4,895,561 $ 3.14 Granted 1,070,000 1.75 Forfeited/Cancelled (220,000 ) 2.68 Exercised — — Outstanding, December 31, 2022 5,745,561 $ 2.90 7.38 $ 30 Exercisable, December 31, 2022 3,551,395 $ 3.35 6.71 $ 29 The aggregate intrinsic value in the table above represents the total pre-tax amount, net of exercise price, which would have been received by option holders if all option holders had exercised all options with an exercise price lower than the market price on December 31, 2022, based on the closing price of the Company’s common stock of $1.13 on that date. The weighted-average grant-date fair values of options granted during 2022 and 2021 were $1.31 and $1.78, respectively. As of December 31, 2022 and 2021, there were unvested options to purchase 2,194,166 and 2,737,084 shares of common stock, respectively. Total expected unrecognized compensation cost related to such unvested options is $2,209,000 at December 31, 2022, which is expected to be recognized over a weighted-average period of 1.45 years. The aggregate intrinsic value of stock options exercised for the year ended December 31, 2022 and 2021 was $0 and $532,447, respectively. During the years ended December 31, 2022 and 2021, 1,452,918 and 284,583 options became vested, respectively. The total grant date fair value of options vested during the years ended December 31, 2022 and 2021 was $2,382,842 and $514,287, respectively. The following table summarizes additional information regarding outstanding and exercisable options under our stock-based compensation plans at December 31, 2022: Options Outstanding Options Exercisable Exercise Price (Range) Number of Shares Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Shares Weighted Average Exercise Price (in years) $0.87 – 1.00 120,500 3.96 $ 0.89 120,500 $ 0.89 $1.01 – 3.00 4,364,521 8.11 2.19 2,300,356 2.31 $3.01 – 5.00 903,040 5.85 4.14 773,039 4.31 $5.01 – 8.00 220,000 5.11 5.92 220,000 5.92 $8.01 – 13.38 137,500 1.06 13.38 137,500 13.38 5,745,561 7.38 $ 2.90 3,551,395 $ 3.35 Restricted Stock Issuances In March 2021, one director elected to take a restricted stock grant in lieu of cash retainers for 2021. In January 2022, one director elected to take a restricted stock grant in lieu of cash retainers for 202 Deferred Stock Units In September 2020, the Company entered into an employment agreement with its new Chief Executive Officer whereby 20% of his base salary and performance bonuses will be paid in cash, and 80% will be paid in the form of deferred stock units (“ DSUs Pursuant to an amendment to the DSU Agreement in July 2022, the Company shall issue the shares underlying the outstanding whole number of DSUs credited to Mr. Lewis as follows: twenty five percent shall be issued on March 1, 2023, fifty percent shall be issued on March 1, 2024 twenty five percent shall be issued on September 1, 2028 For the year ended December 31, 2022, $418,000 of Mr. Lewis’ compensation was recorded as stock compensation expense representing 268,596 shares of common stock to be issued under the DSU agreement with a weighted average grant date fair value of $1.56 per share. Also, Mr. Lewis’ bonus for the year ended December 31, 2021 of $200,000 (which was included in accrued compensation at December 31, 2021) was approved in January 2022, and represents 103,627 shares of common stock to be issued under the DSU agreement with a grant date fair value of $1.93 per share. The $200,000 was reclassified from accrued compensation to additional paid in capital in January 2022. For the year ended December 31, 2021, $400,000 of Mr. Lewis’ compensation was recorded as stock compensation expense representing 142,206 shares of common stock to be issued under the DSU agreement with a weighted average grant date fair value of $2.81 per share. Also, Mr. Lewis’ bonus for the year ended December 31, 2020 of $60,000 (which was included in accrued compensation at December 31, 2020) was approved in March 2021 and represents 27,027 shares of common stock to be issued under the DSU agreement with a grant date fair value of $2.22 per share. The $60,000 was reclassified from accrued compensation to additional paid in capital in March 2021. There is no unrecognized compensation expense related to the DSUs.

Convertible Line of Credit - Re

Convertible Line of Credit - Related Party	12 Months Ended
	Dec. 31, 2022
Convertible Line of Credit - Related Party [Member]
Debt Instrument [Line Items]
Convertible Line of Credit - Related Party	10. Convertible Line of Credit – Related Party On July 25, 2022, the Company and Richard E. Uihlein (the “Lender”) entered into a Line of Credit Letter Agreement (the “Credit Agreement”), pursuant to which the Lender shall provide the Company a line of credit of up to $60.0 million (the “Line of Credit”) to finance the Company’s working capital needs. The Company may draw upon the Line of Credit through July 31, 2024. Each advance made pursuant to the Credit Agreement shall be evidenced by an unsecured, convertible promissory note (individually, a “Promissory Note,” and collectively, the “Promissory Notes”), and bear interest at the Applicable Federal Rate for short term loans, plus two (2%) percent. Principal and interest on the Promissory Notes are due on or before January 31, 2026. Only with the consent of the Lender, may the Promissory Notes be prepaid, in whole or in part, at any time without premium or penalty, but with interest on the amount or amounts prepaid. At the election of Lender, the principal and accrued interest on Promissory Note(s) may be converted into the number of shares of the Company’s Common Stock equal to the amount of principal and accrued interest on such Promissory Note divided by the price equal to the closing price of the Common Stock on the date of such Promissory Note, but in no event less than $3.00 per share. In connection with the Credit Agreement, the Company agreed to issue the Lender warrants to purchase up to an aggregate of 1,700,000 shares of the Company’s common stock, par value $0.001 per share (collectively, the “Warrants”). Upon execution of the Credit Agreement, the Company issued the Lender a Warrant to purchase up to 500,000 shares of Company’s Common Stock at an exercise price of $5.00 per share, which Warrant is exercisable upon issuance. Further, pursuant to the Credit Agreement, the Company shall issue to the Lender additional Warrants to purchase up to the remaining 1,200,000 shares of the Company’s common stock, ratably, upon borrowings under the Credit Agreement, with exercise prices equal to 150% of the closing price of the Company’s common Stock on the date of the Promissory Note evidencing such draw, but in no event more than $10.00 per share nor less than $3.00 per share. The Warrants expire on July 31, 2029. The fair value of the 500,000 warrants vested at closing on July 25, 2022 was $738,000 at the date of issuance based on the following assumptions: an expected life of 7 years, volatility of 92%, risk free interest rate of 3.19% and zero dividends. The fair value of the vested warrants was recorded in other assets (non-current) as a deferred financing cost and will be amortized on a straight-line basis from July 25, 2022 through January 31, 2026. Amortization for the period ended December 31, 2022 of $92,000 was recorded as interest expense. On December 19, 2022, the Company executed a $10 million Promissory Note under the Line of Credit. The interest rate on this draw is 6.4% (Applicable Federal Rate for short term loans on date of draw of 4.46% plus 2%). The effective interest rate is approximately 7.1%. Accrued interest on this draw was $23,000 at December 31, 2022. The principal and accrued interest is convertible at the option of the Lender at $3.00 per share. In accordance with the Credit Agreement, the Company issued the Lender a Warrant to purchase up to 200,000 shares of Company’s Common Stock at an exercise price of $3.00 per share, which Warrant is exercisable upon issuance. The fair value of the 200,000 warrants vested at closing on December 19, 2022 was $160,780 at the date of issuance based on the following assumptions: an expected life of 7 years, volatility of 91%, risk free interest rate of 4.06% and zero dividends. The proceeds were allocated between the Promissory Note and the warrants issued, and the amount allocated to the warrants was recorded as a debt discount netted against principal to be amortized on a straight-line basis, which is not materially different than the effective interest method, from December 19, 2022 through January 31, 2026. Amortization for the period ended December 31, 2022 of $2,000 was recorded as interest expense. The fair value of warrants that vest in the future based on borrowings will be computed when those borrowings occur and amortized over the remaining period through January 31, 2026.

Loss Per Share

Loss Per Share	12 Months Ended
	Dec. 31, 2022
Loss Per Share [Abstract]
Loss Per Share	11. Loss Per Share Basic net loss per common share is computed by dividing the net loss available to common stockholders by the weighted average number of common shares outstanding during the period. For the years ended December 31, 2022 and 2021, as the Company was in a net loss position, the diluted loss per share computations for such periods did not assume the exercise of warrants and stock options or the conversion of Convertible Notes, or the conversion of convertible preferred stock as they would have had an anti-dilutive effect on loss per share. The following potentially dilutive securities have been excluded from the computations of diluted weighted average shares outstanding as of December 31, 2022 and 2021 as the inclusion thereof would have been anti-dilutive: Year Ended December 31, 2022 (Shares) 2021 (Shares) Warrants to purchase shares of common stock 11,557,964 10,857,964 Options to purchase shares of common stock 5,745,561 4,895,561 Shares of common stock issuable upon conversion of convertible notes payable – related party 5,815,514 5,214,806 Shares of common stock issuable upon conversion of convertible line of credit – related party 3,341,003 - Shares of common stock issuable upon conversion preferred stock 503,340 510,424 26,963,382 21,478,755

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies Lease Commitments The Company has one operating lease for its office space which was amended effective March 1, 2022 for a term of 38 months with no residual value guarantees or material restrictive covenants. The amended lease provided for free rent for the first six and one-half months other assets accrued expenses other long term liabilities The Company renewed its existing office space lease effective in February 2022 for 38 months at substantially the same terms. Maturity of operating lease as of December 31, 2022 in thousands: 2023 $ 50 2024 51 2025 18 Total 119 Less imputed interest 13 Present value of lease liability $ 106 The discount rate used in calculating the present value of the lease payments was 11%. Legal Proceedings The Company records accruals for such contingencies to the extent that the Company concludes that their occurrence is probable and the related damages are estimable. There are no pending legal proceedings. Clinical Trial and Research Contingencies The Company has entered into agreements with contractors for research and development activities to further its product candidates. The contracts generally may be canceled at any time by providing thirty days’ notice.

Galectin Sciences LLC

Galectin Sciences LLC	12 Months Ended
	Dec. 31, 2022
Galectin Sciences LLC [Abstract]
Galectin Sciences LLC	13. Galectin Sciences LLC In January 2014, we created Galectin Sciences, LLC (the “LLC” or “Investee”), a collaborative joint venture co-owned by SBH Sciences, Inc. (“SBH”), to research and develop small organic molecule inhibitors of galectin-3 for oral administration. The LLC was initially capitalized with a $400,000 cash investment to fund future research and development activities, which was provided by the Company, and specific in-process research and development (“IPR&D”) contributed by SBH. The estimated fair value of the IPR&D contributed by SBH, on the date of contribution, was $400,000. Initially, the Company and SBH have a 50% equity ownership interest in the LLC, with neither party having control over the LLC. Accordingly, from inception through the fourth quarter of 2014, the Company accounted for its investment in the LLC using the equity method of accounting. Under the equity method of accounting, the Company’s investment was initially recorded at cost with subsequent adjustments to the carrying value to recognize additional investments in or distributions from the Investee, as well as the Company’s share of the Investee’s earnings, losses and/or changes in capital. The estimated fair value of the IPR&D contributed to the LLC was immediately expensed upon contribution as there was no alternative future use available at the point of contribution. The operating agreement provides that if either party does not desire to contribute its equal share of funding required after the initial capitalization, then the other party, providing all of the funding, will have its ownership share increased in proportion to the total amount contributed from inception. In the fourth quarter of 2014, after the LLC had expended the $400,000 in cash, SBH decided not to contribute its share of the funding required. As a result, the Company contributed the $73,000 needed for the fourth quarter of 2014 expenses of the LLC and an additional $2,306,000 in total from 2015 through 2020. The Company contributed $213,000 and $226,000 for the LLC expenses (recorded in research and development expenses) in 2022 and 2021, and SBH contributed $35,000 in 2019 and a total of $123,000 in 2017 and 2016, respectively. As of December 31, 2022, the Company’s ownership percentage in the LLC was 85.3%. The Company accounts for the interest in the LLC as a consolidated, less than wholly owned subsidiary. Because the LLC’s equity is immaterial, the value of the non-controlling interest is also deemed to be immaterial. The Company’s portion of the LLC’s net loss for 2014, prior to the change in accounting discussed previously, was $400,000, which includes the Company’s proportionate share of the non-cash charge associated with the contributed IPR&D of $200,000.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2022
Income Taxes [Abstract]
Income Taxes	14. Income Taxes The components of the net deferred tax assets are as follows at December 31: 2022 2021 (in thousands) Operating loss carryforwards $ 53,119 $ 54,949 Tax credit carryforwards 3,558 3,720 Other temporary differences 9,168 1,652 65,845 60,321 Less valuation allowance (65,845 ) (60,321 ) Net deferred tax asset $ — $ — The primary factors affecting the Company’s income tax rates were as follows: 2022 2021 Tax benefit at U.S. statutory rates (21 %) (21 %) State tax benefit 4.2 % (4.7 %) Permanent differences 0.5 % 0.5 % Other (1.4 %) (0.1 %) Changes in valuation allowance 17.7 % 25.3 % 0 % 0 % As of December 31, 2022, the Company has federal and state net operating loss carryforwards totaling $80,810,000 and $87,141,000, respectively, which will never expire as a result of the 2017 Tax Act. As of December 31, 2022, the Company has federal and state net operating loss carryforwards totaling $131,317,000 and $102,003,000 respectively, which expire through 2037 2042 The Company is subject to taxation in the U.S. and various states. Based on the history of net operating losses all jurisdictions and tax years are open for examination until the operating losses are utilized or the statute of limitations expires. As of December 31, 2022 and 2021, the Company does not have any significant uncertain tax positions.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2022
Summary of Significant Accounting Policies [Abstract]
Basis of Consolidation	Basis of Consolidation. The consolidated financial statements include the accounts of the Company and Galectin Therapeutics Security Corp., its wholly-owned subsidiary, which was incorporated in Delaware on December 23, 2003 and Galectin Sciences LLC (see Note 13). All intercompany transactions have been eliminated.
Use of Estimates	Use of Estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and judgments that may affect the reported amounts of assets, liabilities, equity, revenue, expenses and related disclosure of contingent assets and liabilities. Management’s estimates and judgments include assumptions used in stock option valuations, useful lives of property and equipment and intangible assets, accrued liabilities, derivative valuations, deferred income taxes and various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from those estimates under different assumptions or conditions.
Fair Value Measurements	Fair Value Measurements . The Company has certain financial assets and liabilities recorded at fair value. Fair values determined by Level 1 inputs utilize observable data such as quoted prices in active markets. Fair values determined by Level 2 inputs utilize data points other than quoted prices in active markets that are observable either directly or indirectly. Fair values determined by Level 3 inputs utilize unobservable data points in which there is little or no market data, which require the reporting entity to develop its own assumptions. The estimated value of accounts payable and accrued expenses approximates their carrying value due to their short-term nature. See
Cash and Cash Equivalents	Cash and Cash Equivalents. The Company considers all highly-liquid investments with original maturities of 90 days or less at the time of acquisition to be cash equivalents. The Company had no cash equivalents at December 31, 2022 or 2021.
Prepaid Expenses and Other Current Assets	Prepaid Expenses and Other Current Assets. Prepaid expenses and other assets consist principally of prepaid insurance, deposits related to the NAVIGATE trial and deferred financing costs (see Note 10).
Property and Equipment	Property and Equipment. Property and equipment, including leasehold improvements, are stated at cost, net of accumulated depreciation and amortization, and are depreciated or amortized using the straight-line method over the estimated useful lives of the related assets of generally three years for computers and office equipment, five years for furniture and fixtures and the shorter of the useful life or life of the lease for leasehold improvements.
Security Deposit	Security Deposit. At December 31, 2022 and 2021, the Company had a security deposit of $6,000 for leased office space included in Prepaid Expenses and Other Current Assets.
Long-Lived Assets	Long-Lived Assets. The Company reviews all long-lived assets for impairment whenever events or circumstances indicate the carrying amount of such assets may not be recoverable. Recoverability of assets to be held or used is measured by comparison of the carrying value of the asset to the future undiscounted net cash flows expected to be generated by the asset. If such asset is considered to be impaired, the impairment recognized is measured by the amount by which the carrying value of the asset exceeds the discounted future cash flows expected to be generated by the asset. There were no impairments of long-lived assets at December 31, 2022 or 2021.
Accrued Expenses	Accrued Expenses . As part of the process of preparing our consolidated financial statements, we are required to estimate accrued expenses. This process involves identifying services that third parties have performed on our behalf and estimating the level of service performed and the associated cost incurred on these services as of each balance sheet date in our consolidated financial statements. Examples of estimated accrued expenses include professional service fees, such as those arising from the services of attorneys and accountants and accrued payroll expenses. In connection with these service fees, our estimates are most affected by our understanding of the status and timing of services provided relative to the actual services incurred by the service providers. In the event that we do not identify certain costs that have been incurred or we under- or over-estimate the level of services or costs of such services, our reported expenses for a reporting period could be understated or overstated. The date on which certain services commence, the level of services performed on or before a given date, and the cost of services are often subject to our judgment. We make these judgments based upon the facts and circumstances known to us in accordance with accounting principles generally accepted in the U.S.
Warrants	Warrants. The Company has issued common stock warrants in connection with the execution of certain equity and debt financings. The fair value of warrants is determined using the Black-Scholes option-pricing model using assumptions regarding volatility of our common share price, remaining life of the warrant, and risk-free interest rates at each period end. There were no warrant liabilities as of December 31, 2022 or 2021.
Research and Development Expenses	Research and Development Expenses. Research and development expenses, including personnel costs, allocated facility costs, lab supplies, outside services, contract laboratory costs related to manufacturing drug product, clinical trials and preclinical studies are charged to research and development expense as incurred. The Company accounts for nonrefundable advance payments for goods and services that will be used in future research and development activities as expense when the service has been performed or when the goods have been received. Our current NAVIGATE clinical trial is being supported by third-party contract research organizations, or CROs, and other vendors. We accrue expenses for clinical trial activities performed by CROs based upon the estimated amount of work completed on each trial. For clinical trial expenses and related expenses associated with the conduct of clinical trials, the significant factors used in estimating accruals include the number of patients enrolled, the number of active clinical sites, and the duration for which the patients have been enrolled in the trial. We monitor patient enrollment levels and related activities to the extent possible through internal reviews, review of contractual terms and correspondence with CROs. We base our estimates on the best information available at the time. We monitor patient enrollment levels and related activities to the extent possible through discussions with CRO personnel and based our estimates of clinical trial costs on the best information available at the time. However, additional information may become available to us which will allow us to make a more accurate estimate in future periods. In that event, we may be required to record adjustments to research and development expenses in future periods when the actual level of activity becomes more certain.
Income Taxes	Income Taxes. The Company accounts for income taxes in accordance with the accounting rules that requires an asset and liability approach to accounting for income taxes based upon the future expected values of the related assets and liabilities. Deferred income tax assets and liabilities are determined based on the differences between the financial reporting and tax bases of assets and liabilities and for tax loss and credit carry forwards and are measured using the expected tax rates estimated to be in effect when such basis differences reverse. Valuation allowances are established, if necessary, to reduce the deferred tax asset to the amount that will, more likely than not, be realized.
Concentration of Credit Risk	Concentration of Credit Risk. Financial instruments that subject the Company to credit risk consist of cash and cash equivalents. The Company maintains cash and cash equivalents and certificates of deposit with well-capitalized financial institutions. At times, those amounts may exceed federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant credit risk beyond the normal credit risk associated with commercial banking relationships. The Company has no other significant concentrations of credit risk.
Stock-Based Compensation	Stock-Based Compensation. Stock-based compensation cost is measured at the grant date based on the fair value of the award and is recognized as expense over the service period, which generally represents the vesting period. For awards that have performance-based vesting conditions the Company recognizes the expense over the estimated period that the awards are expected to be earned. The Company generally uses the Black-Scholes option-pricing model to calculate the grant date fair value of stock options. The expense recognized over the service period is required to include an estimate of the awards that will be forfeited.
Recent Accounting Standards	Recent Accounting Standards.

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2022
Property and Equipment [Abstract]
Property and Equipment	Property and equipment consist of the following at December 31: 2022 2021 (in thousands) Leasehold improvements $ 2 $ 2 Computer and office equipment 13 13 Furniture and fixtures 59 59 Total 74 74 Less accumulated depreciation and amortization (74 ) (74 ) Property and equipment — net $ — $ —

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2022
Accrued Expenses [Abstract]
Accrued Expenses	Accrued expenses consist of the following at December 31: 2022 2021 (in thousands) Legal and accounting fees $ 65 $ 68 Accrued compensation 973 728 Lease liability 40 8 Accrued research and development costs and other 7,980 6,359 Total $ 9,058 $ 7,163

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2022
Fair Value of Financial Instruments [Abstract]
Assets and Liabilities Measured and Recorded at Fair Value on Recurring Basis	Level 3 assets and liabilities measured and recorded at fair value on a recurring basis at December 31, 2022 and 2021 were as follows: December 31, 2022 December 31, 2021 Derivative Liability – Contingent Interest April Note $ 249,000 $ 495,000 Derivative Liability – Contingent Interest September Note $ 109,000 $ 250,000 Derivative Liability – Contingent Interest December Note $ 215,000 $ 385,000
April Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Key Assumptions Used in Model at Inception	The April 2021 Note derivative liability – contingent interest was valued using a Monte Carlo Geometric Brownian Stock Path Model. The key assumptions used in the model at December 31, 2022 and 2021 are as follows: December 31, 2022 December 31, 2021 Stock Price $ 1.13 $ 2.07 Conversion Price of conversion feature $ 5.00 $ 5.00 Term 2.29 3.29 years Risk Free Interest Rate 4.41 % 0.97 % Credit Adjusted Discount Rate 14.76 % 8.43 % Volatility 81 % 80 % Dividend Rate 0 % 0 %
Roll Forward of Derivative Liability - Contingent Interest	The roll forward of the April 2021 Note derivative liability – contingent interest is as follows: Balance – December 31, 2020 $ — Issuance of April convertible note payable – related party 420,000 Fair Value Adjustment 75,000 Balance – December 31, 2021 495,000 Fair Value Adjustment (246,000 ) Balance – December 31, 2022 $ 249,000
September Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Key Assumptions Used in Model at Inception	The September 2021 Note derivative liability – contingent interest was valued using a Monte Carlo Geometric Brownian Stock Path Model. The key assumptions used in the model at inception, and at December 31, 2022 and 2021 are as follows: December 31, 2022 December 31, 2021 Stock Price $ 1.13 $ 2.07 Conversion Price of conversion feature $ 8.64 $ 8.64 Term 2.72 years 3.72 years Risk Free Interest Rate 4.22 % 1.12 % Credit Adjusted Discount Rate 14.76 % 8.42 % Volatility 81 % 82 % Dividend Rate 0 % 0 %
Roll Forward of Derivative Liability - Contingent Interest	The roll forward of the September 2021 Note derivative liability – contingent interest is as follows: Balance – December 31, 2020 $ — Issuance of September convertible note payable – related party 433,000 Fair Value Adjustment (183,000 ) Balance – December 31, 2021 250,000 Fair Value Adjustment (141,000 ) Balance – December 31, 2022 $ 109,000
December Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Key Assumptions Used in Model at Inception	The December 2021 Note derivative liability – contingent interest was valued using a Monte Carlo Geometric Brownian Stock Path Model. The key assumptions used in the model at inception, and at December 31, 2022 and 2021 are as follows: December 31, 2022 December 31, 2021 Stock Price $ 1.13 $ 2.07 Conversion Price of conversion feature $ 5.43 $ 5.43 Term 2.97 3.97 Risk Free Interest Rate 4.22 % 1.12 % Credit Adjusted Discount Rate 14.76 % 8.42 % Volatility 83 % 84 % Dividend Rate 0 % 0 %
Roll Forward of Derivative Liability - Contingent Interest	The roll forward of the December 2021 Note derivative liability – contingent interest is as follows: Balance – December 31, 2020 $ — Issuance of September convertible note payable – related party 415,000 Fair Value Adjustment (30,000 ) Balance – December 31, 2021 385,000 Fair Value Adjustment (170,000 ) Balance – December 31, 2022 $ 215,000

Warrants (Tables)

Warrants (Tables)	12 Months Ended
	Dec. 31, 2022
Warrants [Abstract]
Summary of Warrants Activity, Outstanding Warrants Issued in Connection with Equity and Debt Financings and Consultants	Warrant activity is summarized as follows: Warrants Weighted average exercise price Outstanding at December 31, 2020 12,538,204 $ 4.22 Issued — Exercised (1,180,240 ) 2.50 Canceled (500,000 ) 5.00 Outstanding at December 31, 2021 10,857,964 $ 4.37 Issued 700,000 4.43 Exercised — Canceled — Outstanding at December 31, 2022 11,557,964 $ 4.37 The following table summarizes information with regard to outstanding warrants issued in connection with equity and debt financings and consultants as of December 31, 2022. Issued in Connection With Number Issued Exercise Price Exercisable Date Expiration Date February 12, 2009 3.00 1,200,000 $ 3.00 February 12, 2009 February 12, 2024 May 13, 2009 3.00 600,000 $ 3.00 May 13, 2009 May 13, 2024 June 30, 2009 3.00 333,333 $ 3.00 June 30, 2009 June 30, 2024 August 12, 2009 3.00 200,000 $ 3.00 August 12, 2009 August 12, 2024 September 30, 2009 3.00 216,666 $ 3.00 September 30, 2009 September 30, 2024 November 4, 2009 3.00 106,666 $ 3.00 November 4, 2009 November 4, 2024 December 8, 2009 3.00 133,143 $ 3.00 December 8, 2009 December 8, 2024 January 29, 2010 3.00 216,667 $ 3.00 January 29, 2010 January 29, 2025 March 8, 2010 3.00 223,334 $ 3.00 March 8, 2010 March 8, 2025 April 30, 2010 3.00 204,192 $ 3.00 April 30, 2010 April 30, 2025 May 10, 2010 3.00 143,166 $ 3.00 May 10, 2010 May 10, 2025 September 22, 2016 3.00 698,158 $ 3.00 September 22, 2016 September 22, 2023 September 29, 2016 3.00 846,100 $ 3.00 September 29, 2016 September 29, 2023 December 22, 2016 1,466,204 $ 5.00 December 22, 2016 December 23, 2023 December 23, 2016 3.00 924,780 $ 3.00 December 23, 2016 December 23, 2023 December 28, 2016 644,468 $ 5.00 December 28, 2016 December 28, 2023 February 27, 2017 76,776 $ 5.00 February 27, 2017 February 27, 2024 2018 and 2017 Warrants issued for services 2,157 $ 5.00 Various dates in 2018 and 2017 Various dates in 2025 and 2024 May 23, 2019 2,622,154 $ 7.00 May 23, 2019 May 23, 2026 July 22, 2022 500,000 $ 5.00 July 22, 2022 July 31, 2029 December 19, 2022 200,000 $ 3.00 December 19, 2022 July 31, 2029 Total outstanding warrants 11,557,964

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2022
Stock-Based Compensation [Abstract]
Components of Stock-Based Compensation Expense	Following is the stock-based compensation expense related to common stock options, restricted common stock, common stock warrants and deferred stock units: Year Ended December 31, 2022 2021 Research and development $ 810 $ 420 General and administrative 2,057 1,656 Total stock-based compensation expense $ 2,867 $ 2,076
Weighted Average Assumptions Used to Determine Fair Value of Options Granted	The fair value of the options granted is determined using the Black-Scholes option-pricing model. The following weighted average assumptions were used: 2022 2021 Risk-free interest rate 1.85 % 0.66 % Expected life of the options 5.7 years 6.0 years Expected volatility of the underlying stock 93.7 % 91.7 % Expected dividend rate 0 % 0 %
Stock Option Activity	The following table summarizes the stock option activity in the stock-based compensation plans: Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value (in thousands) Outstanding, December 31, 2020 3,987,575 $ 4.29 Granted 2,660,000 2.39 Forfeited/Cancelled (1,603,073 ) 5.31 Exercised (148,941 ) 2.35 Outstanding, December 31, 2021 4,895,561 $ 3.14 Granted 1,070,000 1.75 Forfeited/Cancelled (220,000 ) 2.68 Exercised — — Outstanding, December 31, 2022 5,745,561 $ 2.90 7.38 $ 30 Exercisable, December 31, 2022 3,551,395 $ 3.35 6.71 $ 29
Outstanding and Exercisable Options under Stock Based Compensation Plans	The following table summarizes additional information regarding outstanding and exercisable options under our stock-based compensation plans at December 31, 2022: Options Outstanding Options Exercisable Exercise Price (Range) Number of Shares Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Shares Weighted Average Exercise Price (in years) $0.87 – 1.00 120,500 3.96 $ 0.89 120,500 $ 0.89 $1.01 – 3.00 4,364,521 8.11 2.19 2,300,356 2.31 $3.01 – 5.00 903,040 5.85 4.14 773,039 4.31 $5.01 – 8.00 220,000 5.11 5.92 220,000 5.92 $8.01 – 13.38 137,500 1.06 13.38 137,500 13.38 5,745,561 7.38 $ 2.90 3,551,395 $ 3.35

Loss Per Share (Tables)

Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2022
Loss Per Share [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share	The following potentially dilutive securities have been excluded from the computations of diluted weighted average shares outstanding as of December 31, 2022 and 2021 as the inclusion thereof would have been anti-dilutive: Year Ended December 31, 2022 (Shares) 2021 (Shares) Warrants to purchase shares of common stock 11,557,964 10,857,964 Options to purchase shares of common stock 5,745,561 4,895,561 Shares of common stock issuable upon conversion of convertible notes payable – related party 5,815,514 5,214,806 Shares of common stock issuable upon conversion of convertible line of credit – related party 3,341,003 - Shares of common stock issuable upon conversion preferred stock 503,340 510,424 26,963,382 21,478,755

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies [Abstract]
Maturity of Operating Lease	Maturity of operating lease as of December 31, 2022 in thousands: 2023 $ 50 2024 51 2025 18 Total 119 Less imputed interest 13 Present value of lease liability $ 106

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2022
Income Taxes [Abstract]
Components of Net Deferred Tax Assets	The components of the net deferred tax assets are as follows at December 31: 2022 2021 (in thousands) Operating loss carryforwards $ 53,119 $ 54,949 Tax credit carryforwards 3,558 3,720 Other temporary differences 9,168 1,652 65,845 60,321 Less valuation allowance (65,845 ) (60,321 ) Net deferred tax asset $ — $ —
Primary Factors Affecting Income Tax Rates	The primary factors affecting the Company’s income tax rates were as follows: 2022 2021 Tax benefit at U.S. statutory rates (21 %) (21 %) State tax benefit 4.2 % (4.7 %) Permanent differences 0.5 % 0.5 % Other (1.4 %) (0.1 %) Changes in valuation allowance 17.7 % 25.3 % 0 % 0 %

Nature of Business, Basis of _2

Nature of Business, Basis of Presentation and Liquidity (Details) - USD ($)	Dec. 31, 2022	Jul. 25, 2022	Dec. 31, 2021
Nature of Business, Basis of Presentation and Liquidity [Abstract]
Cash and cash equivalents	$ 18,592,000		$ 39,648,000
Richard E. Uihlein [Member] | Unsecured Convertible Promissory Note [Member]
Nature of Business, Basis of Presentation and Liquidity [Abstract]
Line of credit		$ 60,000,000

Summary of Significant Accoun_3

Summary of Significant Accounting Policies, Cash and Cash Equivalents (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents [Abstract]
Cash equivalents	$ 0	$ 0

Summary of Significant Accoun_4

Summary of Significant Accounting Policies, Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2022
Computer and Office Equipment [Member]
Property and Equipment [Abstract]
Estimated useful life	3 years
Furniture and Fixtures [Member]
Property and Equipment [Abstract]
Estimated useful life	5 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies, Security Deposit (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Security Deposit [Abstract]
Security deposit for leased office space	$ 6,000	$ 6,000

Summary of Significant Accoun_6

Summary of Significant Accounting Policies, Long-Lived Assets (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Long-Lived Assets [Abstract]
Impairment of long-lived assets	$ 0	$ 0

Summary of Significant Accoun_7

Summary of Significant Accounting Policies, Warrants (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Warrants [Abstract]
Warrant liabilities	$ 0	$ 0

Property and Equipment (Details

Property and Equipment (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Property and Equipment [Abstract]
Property and equipment	$ 74,000	$ 74,000
Less accumulated depreciation and amortization	(74,000)	(74,000)
Property and equipment - net	0	0
Depreciation and amortization expense	0	0
Leasehold Improvements [Member]
Property and Equipment [Abstract]
Property and equipment	2,000	2,000
Computer and Office Equipment [Member]
Property and Equipment [Abstract]
Property and equipment	13,000	13,000
Furniture and Fixtures [Member]
Property and Equipment [Abstract]
Property and equipment	$ 59,000	$ 59,000

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Accrued Expenses [Abstract]
Legal and accounting fees	$ 65,000	$ 68,000
Accrued compensation	973,000	728,000
Lease liability	$ 40,000	$ 8,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total	Total
Accrued research and development costs and other	$ 7,980,000	$ 6,359,000
Total	$ 9,058,000	$ 7,163,000

Convertible Notes Payable - R_2

Convertible Notes Payable - Related Party (Details)								12 Months Ended
	Dec. 30, 2025 USD ($)	Sep. 17, 2025 USD ($)	Apr. 16, 2025 USD ($)	Dec. 31, 2021 USD ($)	Dec. 20, 2021 USD ($) PromissoryNote $ / shares	Sep. 17, 2021 USD ($) PromissoryNote loan	Apr. 16, 2021 USD ($)	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2021 USD ($)
Convertible Notes Payable - Related Party [Abstract]
Fair value of derivative liability				$ 1,130,000				$ 573,000	$ 1,130,000
Change in fair value of derivative								(557,000)	(138,000)
April Note [Member]
Convertible Notes Payable - Related Party [Abstract]
Change in fair value of derivative								(246,000)	75,000
Amortization of debt discount								420,000
Additional interest expense								$ 105,000	74,000
April Note [Member] | Forecast [Member]
Convertible Notes Payable - Related Party [Abstract]
Convertible note payable repayment			$ 10,000,000
April Note [Member] | Richard E. Uihlein [Member]
Convertible Notes Payable - Related Party [Abstract]
Debt financing arrangement							$ 10,000,000
Convertible note principal							$ 10,000,000
Maturity date								Apr. 16, 2025
Conversion price (in dollars per share) | $ / shares								$ 5
Interest rate compounded annually								2%
Effective interest rate								3%
Accrued interest expense								$ 200,000	142,000
Additional interest rate per quarter							2.50%
Additional interest rate per annum from issuance date to maturity date period							10%
Fair value of derivative liability				495,000			$ 420,000	249,000	495,000
September Note [Member]
Convertible Notes Payable - Related Party [Abstract]
Change in fair value of derivative								(141,000)	(183,000)
Amortization of debt discount								433,000
Additional interest expense								$ 108,000	32,000
September Note [Member] | Forecast [Member]
Convertible Notes Payable - Related Party [Abstract]
Convertible note payable repayment		$ 10,000,000
September Note [Member] | Richard E. Uihlein [Member]
Convertible Notes Payable - Related Party [Abstract]
Debt financing arrangement						$ 20,000,000
Maturity date								Sep. 17, 2025
Number of loans closing | loan						2
Number of promissory notes evidenced by loans agreement | PromissoryNote						2
Number of promissory notes executed | PromissoryNote						2
Conversion price (in dollars per share) | $ / shares								$ 8.64
Interest rate compounded annually								2%
Effective interest rate								3%
Accrued interest expense								$ 200,000	58,000
Additional interest rate per quarter						2.50%
Additional interest rate per annum from issuance date to maturity date period						10%
Fair value of derivative liability				250,000		$ 433,000		109,000	250,000
First Closing [Member] | Richard E. Uihlein [Member]
Convertible Notes Payable - Related Party [Abstract]
Debt financing arrangement						$ 10,000,000
Second Closing [Member] | Richard E. Uihlein [Member]
Convertible Notes Payable - Related Party [Abstract]
Debt financing arrangement					$ 10,000,000
December Note [Member]
Convertible Notes Payable - Related Party [Abstract]
Convertible note principal					$ 10,000,000
Maturity date					Dec. 20, 2025
Number of promissory notes evidenced by loans agreement | PromissoryNote					2
Conversion price (in dollars per share) | $ / shares					$ 5.43
Interest rate compounded annually					2%
Effective interest rate					3%
Accrued interest expense								200,000	7,000
Additional interest rate per quarter					2.50%
Additional interest rate per annum from issuance date to maturity date period					10%
Fair value of derivative liability				385,000	$ 415,000			214,000	385,000
Change in fair value of derivative				$ (170,000)					(30,000)
Amortization of debt discount								415,000
Additional interest expense								$ 104,000	$ 3,000
December Note [Member] | Forecast [Member]
Convertible Notes Payable - Related Party [Abstract]
Convertible note payable repayment	$ 10,000,000

Fair Value of Financial Instr_3

Fair Value of Financial Instruments, Assets and Liabilities Measured at Fair Value (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	$ 573,000	$ 1,130,000
April Note [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	249,000	495,000	$ 0
September Note [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	109,000	250,000	0
December Note [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	215,000	$ 385,000	$ 0
Recurring [Member] | April Note [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	495,000
Recurring [Member] | April Note [Member] | Level 3 [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	249,000
Recurring [Member] | September Note [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	250,000
Recurring [Member] | September Note [Member] | Level 3 [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	109,000
Recurring [Member] | December Note [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	385,000
Recurring [Member] | December Note [Member] | Level 3 [Member]
Assets and Liabilities Measured at Fair Value [Abstract]
Derivative Liability - Contingent Interest	$ 215,000

Fair Value of Financial Instr_4

Fair Value of Financial Instruments, Key Assumptions (Details)				12 Months Ended
	Dec. 20, 2021	Sep. 17, 2021	Apr. 16, 2021	Dec. 31, 2022
Stock Price [Member] | April Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input			1.13	2.07
Stock Price [Member] | September Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input		1.13		2.07
Stock Price [Member] | December Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input	1.13			2.07
Conversion Price of Conversion Feature [Member] | April Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input			5	5
Conversion Price of Conversion Feature [Member] | September Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input		8.64		8.64
Conversion Price of Conversion Feature [Member] | December Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input	5.43			5.43
Term [Member] | April Note [Member]
Key Assumptions [Abstract]
Term			2 years 3 months 14 days	3 years 3 months 14 days
Term [Member] | September Note [Member]
Key Assumptions [Abstract]
Term		2 years 8 months 19 days		3 years 8 months 19 days
Term [Member] | December Note [Member]
Key Assumptions [Abstract]
Term	2 years 11 months 19 days			3 years 11 months 19 days
Risk Free Interest Rate [Member] | April Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input			0.0441	0.0097
Risk Free Interest Rate [Member] | September Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input		0.0422		0.0112
Risk Free Interest Rate [Member] | December Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input	0.0422			0.0112
Credit Adjusted Discount Rate [Member] | April Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input			0.1476	0.0843
Credit Adjusted Discount Rate [Member] | September Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input		0.1476		0.0842
Credit Adjusted Discount Rate [Member] | December Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input	0.1476			0.0842
Volatility [Member] | April Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input			0.81	0.80
Volatility [Member] | September Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input		0.81		0.82
Volatility [Member] | December Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input	0.83			0.84
Dividend Rate [Member] | April Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input			0	0
Dividend Rate [Member] | September Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input		0		0
Dividend Rate [Member] | December Note [Member]
Key Assumptions [Abstract]
Derivative liability, measurement input	0			0

Fair Value of Financial Instr_5

Fair Value of Financial Instruments, Roll Forward of Derivative Liability (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Roll Forward of Derivative Liability [Roll Forward]
Balance	$ 1,130,000
Fair Value Adjustment	(557,000)	$ (138,000)
Balance	573,000	1,130,000
April Note [Member]
Roll Forward of Derivative Liability [Roll Forward]
Balance	495,000	0
Issuance of convertible note payable - related party		420,000
Fair Value Adjustment	(246,000)	75,000
Balance	249,000	495,000
September Note [Member]
Roll Forward of Derivative Liability [Roll Forward]
Balance	250,000	0
Issuance of convertible note payable - related party		433,000
Fair Value Adjustment	(141,000)	(183,000)
Balance	109,000	250,000
December Note [Member]
Roll Forward of Derivative Liability [Roll Forward]
Balance	385,000	0
Issuance of convertible note payable - related party		415,000
Fair Value Adjustment	(170,000)	(30,000)
Balance	$ 215,000	$ 385,000

Stockholders' Equity, Issuance

Stockholders' Equity, Issuance of Common Stock (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Stockholders' Equity [Abstract]
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Undesignated stock, shares authorized (in shares)	20,000,000	20,000,000
Convertible preferred stock, shares authorized (in shares)	1,742,500	1,742,500
Issuance of common stock (in shares)	59,426,005	59,341,305
Net proceeds from issuance of common stock	$ 0	$ 6,814,000
2020 Market Agreement [Member]
Stockholders' Equity [Abstract]
Aggregate offering price		$ 40,000,000
Percentage of commission rate to be paid to sales agent		3%
Issuance of common stock (in shares)	0	845,214
Net proceeds from issuance of common stock		$ 3,864,000
Common Stock [Member]
Stockholders' Equity [Abstract]
Convertible preferred stock, shares authorized (in shares)	12,748,500
Series A 12% Convertible Preferred Stock [Member]
Stockholders' Equity [Abstract]
Convertible preferred stock, shares authorized (in shares)	1,742,500
Series B-1 Convertible Preferred Stock [Member]
Stockholders' Equity [Abstract]
Convertible preferred stock, shares authorized (in shares)	900,000
Series B-2 Convertible Preferred Stock [Member]
Stockholders' Equity [Abstract]
Convertible preferred stock, shares authorized (in shares)	2,100,000
Series B-3 Convertible Preferred Stock [Member]
Stockholders' Equity [Abstract]
Convertible preferred stock, shares authorized (in shares)	2,508,000
Series C 6% Super Dividend Redeemable Convertible Preferred Stock [Member]
Stockholders' Equity [Abstract]
Convertible preferred stock, shares authorized (in shares)	1,000

Stockholders' Equity, Series A

Stockholders' Equity, Series A 12% Convertible Preferred Stock (Details) - $ / shares		12 Months Ended
	Feb. 04, 2008	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Stockholders' Equity [Abstract]
Share price (in dollars per share)		$ 1.13
Series A 12% Convertible Preferred Stock [Member]
Stockholders' Equity [Abstract]
Preferred stock, dividend rate	12%
Shares issued, price (in dollars per share)	$ 6
Number of shares issued upon exercise of warrant (in shares)	1
Weighted average price percentage	100%
Convertible preferred stock (in shares)		42,500	0	465,000
Common stock issued upon conversion (in shares)		7,287		73,865
Series A 12% Convertible Preferred Stock [Member] | Scenario 1 [Member]
Stockholders' Equity [Abstract]
Exercise price of warrant (in dollars per share)	$ 9
Number of consecutive trading days	20 days
Series A 12% Convertible Preferred Stock [Member] | Scenario 2 [Member]
Stockholders' Equity [Abstract]
Exercise price of warrant (in dollars per share)	$ 12
Number of consecutive trading days	15 days
Series A 12% Convertible Preferred Stock [Member] | Minimum [Member]
Stockholders' Equity [Abstract]
Share price (in dollars per share)	$ 18

Stockholders' Equity, Series C

Stockholders' Equity, Series C 6% Super Dividend Redeemable Convertible Preferred Stock (Details) - USD ($)						1 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Jul. 31, 2011	Dec. 30, 2010	Dec. 29, 2010	Jan. 31, 2011	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2018	Dec. 31, 2017
Redeemable Convertible Preferred Stock [Abstract]
Warrants issued (in shares)							11,557,964
Common stock shares outstanding (in shares)							59,426,005	59,341,305
Minimum closing price of common stock (in dollars per share)							$ 1.13
Common Stock [Member]
Redeemable Convertible Preferred Stock [Abstract]
Preferred stock issued (in shares)								845,214
Series C 6% Super Dividend Redeemable Convertible Preferred Stock [Member]
Redeemable Convertible Preferred Stock [Abstract]
Preferred stock issued (in shares)				212		13
Preferred stock par value (in dollars per share)					$ 0.01
Shares issued, price (in dollars per share)				$ 10,000		$ 10,000
Stated value of dividend payment (in dollars per share)				$ 10,000
Gross proceeds from issuance of preferred stock				$ 2,120,000		$ 130,000
Transaction costs				47,000
Net proceeds from issuance of preferred stock				$ 2,073,000
Warrants issued (in shares)				500
Exercise price of warrant (in dollars per share)				$ 7.2
Common stock share conversion price (in dollars per share)				$ 6
Common stock shares issued (in shares)				1,667
Preferred stock shares upon conversion (in shares)	33,756	40,193	8,334	293,340
Number of consecutive trading days				15 days			10 days
Preferred stock, dividend rate				6%
Preferred stock redemption price (in dollars per share)				$ 3			$ 3
Post conversion dividend rights (in shares)	20	24	5
Post conversion redemption right, return on investment multiplier amount							$ 10,000
Closing days after conversion rights							30 days
Series C 6% Super Dividend Redeemable Convertible Preferred Stock [Member] | Maximum [Member]
Redeemable Convertible Preferred Stock [Abstract]
Preferred stock issued (in shares)					1,000
Stated value of dividend payment (in dollars per share)					$ 10,000
Convertible preferred stock dividend				$ 100,000
Series C 6% Super Dividend Redeemable Convertible Preferred Stock [Member] | Common Stock [Member]
Redeemable Convertible Preferred Stock [Abstract]
Common stock shares outstanding (in shares)									176	176
Minimum closing price of common stock (in dollars per share)				$ 18
Series C 6% Super Dividend Redeemable Convertible Preferred Stock [Member] | Dividend Payment Scenario One [Member]
Redeemable Convertible Preferred Stock [Abstract]
Dividend as percentage of net sales				2.50%
Series C 6% Super Dividend Redeemable Convertible Preferred Stock [Member] | Dividend Payment Scenario Two [Member]
Redeemable Convertible Preferred Stock [Abstract]
Dividend as percentage of net sales				1.25%

Stockholders' Equity, Return on

Stockholders' Equity, Return on Investment (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) Rights	Dec. 31, 2021 USD ($)
ROI Percentage [Abstract]
ROI before second anniversary of date of issuance	200%
ROI after second anniversary but before third anniversary of date of issuance	250%
ROI after third anniversary but before fourth anniversary of date of issuance	300%
ROI after fourth anniversary but before fifth anniversary of date of issuance	350%
ROI after fifth anniversary but before sixth anniversary of date of issuance	400%
ROI after sixth anniversary but before seventh anniversary of date of issuance	450%
ROI after seventh anniversary but before eighth anniversary of date of issuance	500%
ROI after eighth anniversary but before ninth anniversary of date of issuance	550%
Redeemable Convertible Preferred Stock [Abstract]
Convertible preferred stock, redemption value	$ 8,335,000
Series C 6% Super Dividend Redeemable Convertible Preferred Stock [Member]
Redeemable Convertible Preferred Stock [Abstract]
Convertible preferred stock, redemption value		$ 8,335,000
Convertible preferred stock, voting rights | Rights	0

Warrants, Summary of Warrant Ac

Warrants, Summary of Warrant Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Weighted Average Exercise Price [Abstract]
Outstanding at beginning of period (in dollars per share)	$ 4.37	$ 4.22
Issued (in dollars per share)	4.43
Exercised (in dollars per share)		2.5
Cancelled (in dollars per share)		5
Outstanding at end of period (in dollars per share)	$ 4.37	$ 4.37
Warrants [Member]
Warrants Activity [Roll Forward]
Outstanding at beginning of period (in shares)	10,857,964	12,538,204
Issued (in shares)	700,000	0
Exercised (in shares)	0	(1,180,240)
Cancelled (in shares)	0	(500,000)
Outstanding at end of period (in shares)	11,557,964	10,857,964

Warrants, Summary of Outstandin

Warrants, Summary of Outstanding Warrants Issued in Connection with Equity and Debt Financing and Consultants (Details)	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	11,557,964
February 12, 2009 Series B-1 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	1,200,000
Exercise price (in dollars per share)	$ 3
Exercisable date	Feb. 12, 2009
Expiration date	Feb. 12, 2024
Warrant issue date	Feb. 12, 2009
Warrants issued price (in dollars per share)	$ 3
May 13, 2009 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	600,000
Exercise price (in dollars per share)	$ 3
Exercisable date	May 13, 2009
Expiration date	May 13, 2024
Warrant issue date	May 13, 2009
Warrants issued price (in dollars per share)	$ 3
June 30, 2009 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	333,333
Exercise price (in dollars per share)	$ 3
Exercisable date	Jun. 30, 2009
Expiration date	Jun. 30, 2024
Warrant issue date	Jun. 30, 2009
Warrants issued price (in dollars per share)	$ 3
August 12, 2009 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	200,000
Exercise price (in dollars per share)	$ 3
Exercisable date	Aug. 12, 2009
Expiration date	Aug. 12, 2024
Warrant issue date	Aug. 12, 2009
Warrants issued price (in dollars per share)	$ 3
September 30, 2009 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	216,666
Exercise price (in dollars per share)	$ 3
Exercisable date	Sep. 30, 2009
Expiration date	Sep. 30, 2024
Warrant issue date	Sep. 30, 2009
Warrants issued price (in dollars per share)	$ 3
November 4, 2009 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	106,666
Exercise price (in dollars per share)	$ 3
Exercisable date	Nov. 04, 2009
Expiration date	Nov. 04, 2024
Warrant issue date	Nov. 04, 2009
Warrants issued price (in dollars per share)	$ 3
December 8, 2009 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	133,143
Exercise price (in dollars per share)	$ 3
Exercisable date	Dec. 08, 2009
Expiration date	Dec. 08, 2024
Warrant issue date	Dec. 08, 2009
Warrants issued price (in dollars per share)	$ 3
January 29, 2010 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	216,667
Exercise price (in dollars per share)	$ 3
Exercisable date	Jan. 29, 2010
Expiration date	Jan. 29, 2025
Warrant issue date	Jan. 29, 2010
Warrants issued price (in dollars per share)	$ 3
March 8, 2010 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	223,334
Exercise price (in dollars per share)	$ 3
Exercisable date	Mar. 08, 2010
Expiration date	Mar. 08, 2025
Warrant issue date	Mar. 08, 2010
Warrants issued price (in dollars per share)	$ 3
April 30, 2010 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	204,192
Exercise price (in dollars per share)	$ 3
Exercisable date	Apr. 30, 2010
Expiration date	Apr. 30, 2025
Warrant issue date	Apr. 30, 2010
Warrants issued price (in dollars per share)	$ 3
May 10, 2010 Series B-2 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	143,166
Exercise price (in dollars per share)	$ 3
Exercisable date	May 10, 2010
Expiration date	May 10, 2025
Warrant issue date	May 10, 2010
Warrants issued price (in dollars per share)	$ 3
September 22, 2016 Series B-3 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	698,158
Exercise price (in dollars per share)	$ 3
Exercisable date	Sep. 22, 2016
Expiration date	Sep. 22, 2023
Warrant issue date	Sep. 22, 2016
Warrants issued price (in dollars per share)	$ 3
September 29, 2016 Series B-3 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	846,100
Exercise price (in dollars per share)	$ 3
Exercisable date	Sep. 29, 2016
Expiration date	Sep. 29, 2023
Warrant issue date	Sep. 29, 2016
Warrants issued price (in dollars per share)	$ 3
December 22, 2016 Private Placement Warrants [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	1,466,204
Exercise price (in dollars per share)	$ 5
Exercisable date	Dec. 22, 2016
Expiration date	Dec. 23, 2023
Warrant issue date	Dec. 22, 2016
December 23, 2016 Series B-3 Transaction [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	924,780
Exercise price (in dollars per share)	$ 3
Exercisable date	Dec. 23, 2016
Expiration date	Dec. 23, 2023
Warrant issue date	Dec. 23, 2016
Warrants issued price (in dollars per share)	$ 3
December 28, 2016 Private Placement Warrants [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	644,468
Exercise price (in dollars per share)	$ 5
Exercisable date	Dec. 28, 2016
Expiration date	Dec. 28, 2023
Warrant issue date	Dec. 28, 2016
February 27, 2017 Private Placement Warrants [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	76,776
Exercise price (in dollars per share)	$ 5
Exercisable date	Feb. 27, 2017
Expiration date	Feb. 27, 2024
Warrant issue date	Feb. 27, 2017
2018 and 2017 Warrants issued for services [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	2,157
Exercise price (in dollars per share)	$ 5
May 23, 2019 Rights offering warrants [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	2,622,154
Exercise price (in dollars per share)	$ 7
Exercisable date	May 23, 2019
Expiration date	May 23, 2026
Warrant issue date	May 23, 2019
July 22, 2022 Warrants issued in connection of related party line of credit [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	500,000
Exercise price (in dollars per share)	$ 5
Exercisable date	Jul. 22, 2022
Expiration date	Jul. 31, 2029
Warrant issue date	Jul. 22, 2022
December 19, 2022 Warrants issued for draw on related party line of credit [Member]
Outstanding Warrants [Abstract]
Number issued (in shares) | shares	200,000
Exercise price (in dollars per share)	$ 3
Exercisable date	Dec. 19, 2022
Expiration date	Jul. 31, 2029
Warrant issue date	Dec. 19, 2022

Stock-Based Compensation, Summa

Stock-Based Compensation, Summary of Stock-Based Compensation Plans (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	May 31, 2008
Stock-Based Compensation Expense [Abstract]
Non-plan stock option grants to employees and non-employees (in shares)	1,070,000	2,660,000
Non-plan grants outstanding (in shares)	5,745,561	4,895,561	3,987,575
Equity Incentive Plan 2019 [Member]
Stock-Based Compensation Expense [Abstract]
Number of shares authorized for issuance (in shares)	7,000,000			4,000,000
Stock awards, available for future grant (in shares)	1,966,279
Incentive Compensation Plan 2009 [Member]
Stock-Based Compensation Expense [Abstract]
Number of shares authorized for issuance (in shares)					6,733,334

Stock-Based Compensation, Compo

Stock-Based Compensation, Components of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Stock-Based Compensation Expense [Abstract]
Total stock-based compensation expense	$ 2,867	$ 2,076
Research and Development [Member]
Stock-Based Compensation Expense [Abstract]
Total stock-based compensation expense	810	420
General and Administrative [Member]
Stock-Based Compensation Expense [Abstract]
Total stock-based compensation expense	$ 2,057	$ 1,656

Stock-Based Compensation, Weigh

Stock-Based Compensation, Weighted Average Assumptions Used to Determine Fair Value of Options Granted (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Weighted Average Assumptions for Stock Options Granted [Abstract]
Risk-free interest rate	1.85%	0.66%
Expected life of the options	5 years 8 months 12 days	6 years
Expected volatility of the underlying stock	93.70%	91.70%
Expected dividend rate	0%	0%
Expected dividend yield used in the option valuation model	0%	0%
Minimum [Member]
Weighted Average Assumptions for Stock Options Granted [Abstract]
Expected life of the options	5 years
Award term	5 years
Maximum [Member]
Weighted Average Assumptions for Stock Options Granted [Abstract]
Expected life of the options	6 years
Award term	10 years

Stock-Based Compensation, Stock

Stock-Based Compensation, Stock Option Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Stock Option Activity [Roll Forward]
Outstanding at beginning of period (in shares)	4,895,561	3,987,575
Granted (in shares)	1,070,000	2,660,000
Forfeited/cancelled (in shares)	(220,000)	(1,603,073)
Exercised (in shares)	0	(148,941)
Outstanding at end of period (in shares)	5,745,561	4,895,561
Exercisable, end of period (in shares)	3,551,395
Weighted Average Exercise Price [Abstract]
Outstanding at beginning of period (in dollars per share)	$ 3.14	$ 4.29
Granted (in dollars per share)	1.75	2.39
Forfeited/cancelled (in dollars per share)	2.68	5.31
Exercised (in dollars per share)	0	2.35
Outstanding at beginning of period (in dollars per share)	2.9	3.14
Exercisable, end of period (in dollars per share)	$ 3.35
Weighted Average Remaining Contractual Life [Abstract]
Outstanding end of the period	7 years 4 months 17 days
Exercisable, end of the period	6 years 8 months 15 days
Aggregate Intrinsic Value [Abstract]
Outstanding at end of period	$ 30,000
Exercisable, end of period	$ 29,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized [Abstract]
Common stock price (in dollars per share)	$ 1.13
Weighted-average grant-date fair values of options granted (in dollars per share)	$ 1.31	$ 1.78
Unvested option (in shares)	2,194,166	2,737,084
Unrecognized compensation cost	$ 2,209,000
Unrecognized compensation cost, recognition period	1 year 5 months 12 days
Intrinsic value of stock options	$ 0	$ 532,447
Options vested (in shares)	1,452,918	284,583
Total fair value of options vested	$ 2,382,842	$ 514,287

Stock-Based Compensation, Outst

Stock-Based Compensation, Outstanding and Exercisable Options under Stock Based Compensation Plans (Details)	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Options Outstanding [Abstract]
Options Outstanding, Number of Shares (in shares) | shares	5,745,561
Options Outstanding, Weighted Average Remaining Contractual Life	7 years 4 months 17 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 2.9
Options Exercisable [Abstract]
Options Exercisable, Number of Shares (in shares) | shares	3,551,395
Options Exercisable, Number of Shares (in dollars per share)	$ 3.35
$0.87-$1.00 [Member]
Options Outstanding [Abstract]
Options Outstanding, Number of Shares (in shares) | shares	120,500
Options Outstanding, Weighted Average Remaining Contractual Life	3 years 11 months 15 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 0.89
Options Exercisable [Abstract]
Options Exercisable, Number of Shares (in shares) | shares	120,500
Options Exercisable, Number of Shares (in dollars per share)	$ 0.89
$1.01-$3.00 [Member]
Options Outstanding [Abstract]
Options Outstanding, Number of Shares (in shares) | shares	4,364,521
Options Outstanding, Weighted Average Remaining Contractual Life	8 years 1 month 9 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 2.19
Options Exercisable [Abstract]
Options Exercisable, Number of Shares (in shares) | shares	2,300,356
Options Exercisable, Number of Shares (in dollars per share)	$ 2.31
$3.01-$5.00 [Member]
Options Outstanding [Abstract]
Options Outstanding, Number of Shares (in shares) | shares	903,040
Options Outstanding, Weighted Average Remaining Contractual Life	5 years 10 months 6 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 4.14
Options Exercisable [Abstract]
Options Exercisable, Number of Shares (in shares) | shares	773,039
Options Exercisable, Number of Shares (in dollars per share)	$ 4.31
$5.01 - $8.00 [Member]
Options Outstanding [Abstract]
Options Outstanding, Number of Shares (in shares) | shares	220,000
Options Outstanding, Weighted Average Remaining Contractual Life	5 years 1 month 9 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 5.92
Options Exercisable [Abstract]
Options Exercisable, Number of Shares (in shares) | shares	220,000
Options Exercisable, Number of Shares (in dollars per share)	$ 5.92
$8.01-$13.38 [Member]
Options Outstanding [Abstract]
Options Outstanding, Number of Shares (in shares) | shares	137,500
Options Outstanding, Weighted Average Remaining Contractual Life	1 year 21 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 13.38
Options Exercisable [Abstract]
Options Exercisable, Number of Shares (in shares) | shares	137,500
Options Exercisable, Number of Shares (in dollars per share)	$ 13.38
Minimum [Member] | $0.87-$1.00 [Member]
Options Outstanding [Abstract]
Minimum Exercise Price (in dollars per share)	0.87
Minimum [Member] | $1.01-$3.00 [Member]
Options Outstanding [Abstract]
Minimum Exercise Price (in dollars per share)	1.01
Minimum [Member] | $3.01-$5.00 [Member]
Options Outstanding [Abstract]
Minimum Exercise Price (in dollars per share)	3.01
Minimum [Member] | $5.01 - $8.00 [Member]
Options Outstanding [Abstract]
Minimum Exercise Price (in dollars per share)	5.01
Minimum [Member] | $8.01-$13.38 [Member]
Options Outstanding [Abstract]
Minimum Exercise Price (in dollars per share)	8.01
Maximum [Member] | $0.87-$1.00 [Member]
Options Outstanding [Abstract]
Maximum Exercise Price (in dollars per share)	1
Maximum [Member] | $1.01-$3.00 [Member]
Options Outstanding [Abstract]
Maximum Exercise Price (in dollars per share)	3
Maximum [Member] | $3.01-$5.00 [Member]
Options Outstanding [Abstract]
Maximum Exercise Price (in dollars per share)	5
Maximum [Member] | $5.01 - $8.00 [Member]
Options Outstanding [Abstract]
Maximum Exercise Price (in dollars per share)	8
Maximum [Member] | $8.01-$13.38 [Member]
Options Outstanding [Abstract]
Maximum Exercise Price (in dollars per share)	$ 13.38

Stock-Based Compensation, Restr

Stock-Based Compensation, Restricted Stock Issuances (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) Director shares	Dec. 31, 2021 USD ($) Director shares
Share-based Payment Arrangement, Noncash Expense [Abstract]
Amortized expense	$ 2,867,000	$ 2,076,000
Restricted Stock [Member]
Share-based Payment Arrangement, Noncash Expense [Abstract]
Number of Directors | Director	1	1
Restricted stock awards granted (in shares) | shares	17,677	16,588
Amortized expense	$ 35,000	$ 35,000

Stock-Based Compensation, Defer

Stock-Based Compensation, Deferred Stock Units (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Restricted Stock Grants [Abstract]
Unrecognized compensation cost	$ 2,209,000
Chief Executive Officer [Member]
Restricted Stock Grants [Abstract]
Unrecognized compensation cost		$ 0
Chief Executive Officer [Member] | Deferred Bonus [Member]
Restricted Stock Grants [Abstract]
Percentage of base salary paid in cash	20%
Percentage of base salary paid in deferred stock units	80%
Percentage of DSUs shall be credited on March 1, 2021	25%
Percentage of DSUs shall be credited on September 1, 2021	25%
Percentage of DSUs shall be credited on March 1, 2024	50%
Stock based compensation expense	$ 418,000	$ 400,000
Common stock reserved for future issuance (in shares)	268,596	142,206
Common Stock Weighted average Grant Date fair Value (in dollars per share)	$ 1.56	$ 2.81
Chief Executive Officer [Member] | Bonus Shares [Member]
Restricted Stock Grants [Abstract]
Stock based compensation expense	$ 200,000	$ 60,000
Common stock reserved for future issuance (in shares)	103,627	27,027
Common Stock Weighted average Grant Date fair Value (in dollars per share)	$ 1.93	$ 2.22
Reclassification of accrued compensation to additional paid in capital	$ 200,000	$ 60,000

Convertible Line of Credit - _2

Convertible Line of Credit - Related Party (Details) - USD ($)			12 Months Ended
	Dec. 19, 2022	Jul. 25, 2022	Dec. 31, 2022	Dec. 31, 2021
Convertible Line of Credit - Related Party [Abstract]
Share price (in dollars per share)			$ 1.13
Proceeds from lines of credit			$ 10,000,000	$ 0
Common stock, par value (in dollars per share)			$ 0.001	$ 0.001
Expected life			5 years 8 months 12 days	6 years
Expected volatility			93.70%	91.70%
Risk free interest rate			1.85%	0.66%
Expected dividend			0%	0%
Warrants [Member]
Convertible Line of Credit - Related Party [Abstract]
Warrants issuance value		$ 738,000
Expected life			7 years
Expected volatility			92%
Risk free interest rate			3.19%
Expected dividend			0%
Amortization of interest expense			$ 92,000
Warrant One [Member]
Convertible Line of Credit - Related Party [Abstract]
Warrants issuance value	$ 160,780
Expected life			7 years
Expected volatility			91%
Risk free interest rate			4.06%
Expected dividend			0%
Amortization of interest expense			$ 2,000
Minimum [Member]
Convertible Line of Credit - Related Party [Abstract]
Expected life			5 years
Maximum [Member]
Convertible Line of Credit - Related Party [Abstract]
Expected life			6 years
Richard E. Uihlein [Member]
Convertible Line of Credit - Related Party [Abstract]
Common stock, par value (in dollars per share)		$ 0.001
Percentage of warrants equal to the closing price of common stock		150%
Warrants expiry date			Jul. 31, 2029
Richard E. Uihlein [Member] | Warrants [Member]
Convertible Line of Credit - Related Party [Abstract]
Exercise price of warrant (in dollars per share)		$ 5
Richard E. Uihlein [Member] | Warrant One [Member]
Convertible Line of Credit - Related Party [Abstract]
Exercise price of warrant (in dollars per share)	$ 3
Richard E. Uihlein [Member] | Unsecured Convertible Promissory Note [Member]
Convertible Line of Credit - Related Party [Abstract]
Line of credit		$ 60,000,000
Additional short term borrowing interest rate	2%	2%
Borrowings repayment due date		Jan. 31, 2026
Share price (in dollars per share)			$ 3
Proceeds from lines of credit	$ 10,000,000
Interest rate on short term loans	6.40%
Short term borrowing interest rate	4.46%
Short term borrowing effective interest rate	7.10%
Accrued interest			$ 23,000
Richard E. Uihlein [Member] | Unsecured Convertible Promissory Note [Member] | Minimum [Member]
Convertible Line of Credit - Related Party [Abstract]
Share price (in dollars per share)		$ 3
Richard E. Uihlein [Member] | Unsecured Convertible Promissory Note [Member] | Maximum [Member]
Convertible Line of Credit - Related Party [Abstract]
Share price (in dollars per share)		$ 10
Common Stock [Member] | Richard E. Uihlein [Member]
Convertible Line of Credit - Related Party [Abstract]
Warrants to purchase common stock (in shares)		1,700,000
Common Stock [Member] | Richard E. Uihlein [Member] | Maximum [Member]
Convertible Line of Credit - Related Party [Abstract]
Warrants to purchase common stock (in shares)	200,000	500,000
Warrants to purchase additional common stock (in shares)		1,200,000

Loss Per Share, Antidilutive Se

Loss Per Share, Antidilutive Securities (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Abstract]
Amount excluded from calculation (in shares)	26,963,382	21,478,755
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Abstract]
Amount excluded from calculation (in shares)	11,557,964	10,857,964
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Abstract]
Amount excluded from calculation (in shares)	5,745,561	4,895,561
Convertible Notes Payable - Related Party [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Abstract]
Amount excluded from calculation (in shares)	5,815,514	5,214,806
Convertible Line of Credit - Related Party [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Abstract]
Amount excluded from calculation (in shares)	3,341,003	0
Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Abstract]
Amount excluded from calculation (in shares)	503,340	510,424

Commitments and Contingencies_2

Commitments and Contingencies (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) Lease	Dec. 31, 2021 USD ($)	Feb. 28, 2022
Lease Commitments [Abstract]
Number of operating leases | Lease	1
Term of contract	38 months
Free rent period	6 months 15 days
Security deposit	$ 6,000	$ 6,000
Right to use lease asset	$ 86,000
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent
Current lease liability	$ 40,000	$ 8,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued expenses	Accrued expenses
Non-current lease liability	$ 66,000
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other liabilities
Lease renewal term			38 months
Maturity of Operating Lease [Abstract]
2023	$ 50,000
2024	51,000
2025	18,000
Total	119,000
Less imputed interest	13,000
Present value of lease liability	$ 106,000
Discount rate on present value of lease payments	11%
Clinical Trial and Research Contingencies [Abstract]
Contract cancelation notice period	30 days
General and Administrative Expense [Member]
Lease Commitments [Abstract]
Lease cost	$ 43,000	$ 44,000

Galectin Sciences LLC (Details)

Galectin Sciences LLC (Details) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended				24 Months Ended	72 Months Ended
	Jan. 31, 2014	Dec. 31, 2014	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2019	Dec. 31, 2014	Dec. 31, 2017	Dec. 31, 2020
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]
Amount expanded in cash			$ (21,056,000)	$ 12,506,000
Galectin Sciences, LLC [Member]
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]
Initial cash investment	$ 400,000
Ownership percentage			85.30%
Amount expanded in cash		$ 400,000
Contribution for expenses		$ 73,000	$ 213,000	$ 226,000				$ 2,306,000
Loss from equity method investment						$ 400,000
Non-cash charge for in-process research and development						$ 200,000
Galectin Sciences, LLC [Member] | SBH [Member]
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]
Ownership percentage	50%
Contribution for expenses					$ 35,000		$ 123,000
Galectin Sciences, LLC [Member] | SBH [Member] | IPR&D [Member]
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]
Estimated fair value of asset contributed to joint venture	$ 400,000

Income Taxes, Components of Net

Income Taxes, Components of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred Tax Assets [Abstract]
Operating loss carryforwards	$ 53,119	$ 54,949
Tax credit carryforwards	3,558	3,720
Other temporary differences	9,168	1,652
Deferred tax assets, gross	65,845	60,321
Less valuation allowance	(65,845)	(60,321)
Net deferred tax asset	$ 0	$ 0

Income Taxes, Primary Factors A

Income Taxes, Primary Factors Affecting Income Tax Rates (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Primary Factors Affecting Income Tax Rates [Abstract]
Tax benefit at U.S. statutory rates	(21.00%)	(21.00%)
State tax benefit	4.20%	(4.70%)
Permanent differences	0.50%	0.50%
Other	(1.40%)	(0.10%)
Changes in valuation allowance	17.70%	25.30%
Income tax rate, total	0%	0%
Federal and Sate [Abstract]
Deferred tax asset valuation allowance percentage in each of the last two years		100%
Operating loss carryforwards expiration year		2037
Federal and state research and development credits expiration year		2042
Federal [Member]
Federal and Sate [Abstract]
Research and development credits		$ 2,276,000
Federal [Member] | Expiring as a Result of 2017 Tax Act [Member]
Federal and Sate [Abstract]
Net operating loss carryforwards	$ 80,810,000
Federal [Member] | Expiring Through 2037 [Member]
Federal and Sate [Abstract]
Net operating loss carryforwards	131,317,000
State [Member]
Federal and Sate [Abstract]
Research and development credits		$ 1,282,000
State [Member] | Expiring as a Result of 2017 Tax Act [Member]
Federal and Sate [Abstract]
Net operating loss carryforwards	87,141,000
State [Member] | Expiring Through 2037 [Member]
Federal and Sate [Abstract]
Net operating loss carryforwards	$ 102,003,000