Seelos Therapeutics (SEELQ) 10-Q 14 Nov 23 2023 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2023	Nov. 06, 2023
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	000-22245
Entity Registrant Name	SEELOS THERAPEUTICS, INC.
Entity Incorporation, State or Country Code	NV
Entity Tax Identification Number	87-0449967
Entity Address, Address Line One	300 Park Avenue
Entity Address, Address Line Two	2nd Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10022
City Area Code	646
Local Phone Number	293-2100
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	SEEL
Security Exchange Name	NASDAQ
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
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		161,379,805
Entity Central Index Key	0001017491
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets
Cash	$ 2,584	$ 15,533
Grant receivable	221
Prepaid expenses and other current assets	3,383	7,141
Total current assets	6,188	22,674
Operating lease right-of-use asset	30	72
Total assets	6,218	22,746
Current liabilities
Accounts payable	9,320	3,626
Accrued expenses	6,340	7,282
Licenses payable		2,195
Short-term portion of convertible notes payable, at fair value	15,573	11,865
Warrant liabilities, at fair value	4,063	132
Operating lease liability	31	58
Total current liabilities	35,327	25,158
Convertible notes payable, at fair value	1,303	8,184
Operating lease liability, long-term		15
Total liabilities	36,630	33,357
Commitments and contingencies (note 12)
Stockholders' equity (deficit)
Preferred stock, $0.001 par value, 10,000,000 shares authorized, no shares issued or outstanding as of September 30, 2023 and December 31, 2022
Common stock, $0.001 par value, 480,000,000 and 240,000,000 shares authorized, 159,502,724 and 107,168,256 issued and outstanding as of September 30, 2023 and December 31, 2022, respectively	159	107
Additional paid-in-capital	216,602	204,026
Accumulated deficit	(247,173)	(214,744)
Total stockholders' equity (deficit)	(30,412)	(10,611)
Total liabilities and stockholders' equity (deficit)	$ 6,218	$ 22,746

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Condensed Consolidated Balance Sheets
Preferred stock, par value (in USD per share)	$ 0.001	$ 0.001
Preferred stock, authorized (in shares)	10,000,000	10,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in USD per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	480,000,000	240,000,000
Common stock, issued (in shares)	159,502,724	107,168,256
Common stock, outstanding (in shares)	159,502,724	107,168,256

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue
Total revenue	$ 406		$ 1,550
Revenue, Product and Service [Extensible Enumeration]	us-gaap:GrantMember	us-gaap:GrantMember	us-gaap:GrantMember	us-gaap:GrantMember
Operating expense
Research and development	$ 10,022	$ 14,750	$ 24,199	$ 43,115
General and administrative	2,987	2,660	9,839	9,544
Total operating expense	13,009	17,410	34,038	52,659
Loss from operations	(12,603)	(17,410)	(32,488)	(52,659)
Other income (expense)
Interest income	36	36	186	81
Interest expense	(42)	(2)	(56)	(14)
Change in fair value of convertible notes	(799)	(2,137)	(1,349)	(2,477)
Loss on extinguishment of debt	(3,631)		(9,151)
Loss on issuance of common stock and warrants			(4,301)
Change in fair value of warrant liabilities	27,537	(91)	14,730	192
Total other income (expense)	23,101	(2,194)	59	(2,218)
Net income (loss) and comprehensive income (loss)	$ 10,498	$ (19,604)	$ (32,429)	$ (54,877)
Total income (loss) per share basic	$ 0.08	$ (0.18)	$ (0.26)	$ (0.52)
Total loss per share-diluted	$ (0.12)	$ (0.18)	$ (0.26)	$ (0.52)
Weighted-average common shares outstanding used for basic	135,330,494	106,689,924	126,672,513	106,100,413
Weighted-average common shares outstanding used for diluted	148,138,721	106,689,924	126,672,513	106,100,413

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Changes in Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Total
Beginning balance, value at Dec. 31, 2021	$ 105	$ 198,428	$ (141,210)	$ 57,323
Beginning Balance (in shares) at Dec. 31, 2021	105,500,445
Stock-based compensation expense		4,166		4,166
Issuance of common stock, ESPP		99		99
Issuance of common stock, ESPP (in shares)	111,561
Issuance of common stock for prepaid services		167		167
Issuance of common stock for prepaid services (in shares)	200,000
Issuance of common stock for license acquired	$ 1	840		841
Issuance of common stock for license acquired (in shares)	1,000,000
Issuance of common stock in at-the-market offering, net of issuance costs	$ 1	151		152
Issuance of common stock in at-the-market offering, net of issuance costs (in shares)	350,000
Issuance of common stock, options exercised		8		$ 8
Issuance of common stock, options exercised (in shares)	6,250			6,250
Net loss			(54,877)	$ (54,877)
Ending balance, value at Sep. 30, 2022	$ 107	203,859	(196,087)	7,879
Ending Balance (in shares) at Sep. 30, 2022	107,168,256
Beginning balance, value at Jun. 30, 2022	$ 106	202,604	(176,483)	26,227
Beginning Balance (in shares) at Jun. 30, 2022	106,190,773
Stock-based compensation expense		973		973
Issuance of common stock, ESPP		24		24
Issuance of common stock, ESPP (in shares)	27,483
Issuance of common stock for prepaid services		107		107
Issuance of common stock for prepaid services (in shares)	100,000
Issuance of common stock for license acquired (in shares)	500,000
Issuance of common stock in at-the-market offering, net of issuance costs	$ 1	151		152
Issuance of common stock in at-the-market offering, net of issuance costs (in shares)	350,000
Net loss			(19,604)	(19,604)
Ending balance, value at Sep. 30, 2022	$ 107	203,859	(196,087)	7,879
Ending Balance (in shares) at Sep. 30, 2022	107,168,256
Beginning balance, value at Dec. 31, 2022	$ 107	204,026	(214,744)	$ (10,611)
Beginning Balance (in shares) at Dec. 31, 2022	107,168,256			107,168,256
Stock-based compensation expense		3,024		$ 3,024
Issuance of common stock, warrant exercise	$ 19	1,981		2,000
Issuance of common stock, warrant exercise (in shares)	19,331,819
Issuance of common stock for payment of convertible notes payable	$ 6	3,923		3,929
Issuance of common stock for payment of convertible notes payable (in shares)	5,468,461
Issuance of common stock and warrants	$ 27	2,283		2,310
Issuance of common stock and warrants (in shares)	27,059,298
Issuance of common stock, ESPP		97		97
Issuance of common stock, ESPP (in shares)	149,122
Issuance of common stock for prepaid services		190		190
Issuance of common stock for prepaid services (in shares)	250,000
Issuance of common stock in at-the-market offering, net of issuance costs		68		$ 68
Issuance of common stock in at-the-market offering, net of issuance costs (in shares)	75,768
Repurchase and retirement of common stock	$ (1)	1
Repurchase and retirement of common stock (in shares)	(1,000,000)
Issuance of common stock, options exercised (in shares)				0
Issuance of common stock for convertible note amendment	$ 1	1,009		$ 1,010
Issuance of common stock for convertible note amendment (in shares)	1,000,000
Net loss			(32,429)	(32,429)
Ending balance, value at Sep. 30, 2023	$ 159	216,602	(247,173)	$ (30,412)
Ending Balance (in shares) at Sep. 30, 2023	159,502,724			159,502,724
Beginning balance, value at Jun. 30, 2023	$ 124	210,367	(257,671)	$ (47,180)
Beginning Balance (in shares) at Jun. 30, 2023	124,188,236
Stock-based compensation expense		974		974
Issuance of common stock, warrant exercise	$ 19	1,981		2,000
Issuance of common stock, warrant exercise (in shares)	19,331,819
Issuance of common stock for payment of convertible notes payable	$ 1	961		962
Issuance of common stock for payment of convertible notes payable (in shares)	925,192
Issuance of common stock and warrants	$ 15	2,283		2,298
Issuance of common stock and warrants (in shares)	15,000,000
Issuance of common stock, ESPP		36		36
Issuance of common stock, ESPP (in shares)	57,477
Net loss			10,498	10,498
Ending balance, value at Sep. 30, 2023	$ 159	$ 216,602	$ (247,173)	$ (30,412)
Ending Balance (in shares) at Sep. 30, 2023	159,502,724			159,502,724

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities
Net loss	$ (32,429)	$ (54,877)
Adjustments to reconcile net loss to net cash used in operating activities
Stock-based compensation expense	3,024	4,166
Change in fair value of warrant liability	(14,730)	(192)
Change in fair value of convertible notes payable	1,349	2,477
Research and development expense - license amendment		841
Loss on issuance of common stock and warrants	4,301
Amortization of right-of-use asset	42
Net loss on extinguishment of debt	9,151
Changes in operating assets and liabilities
Grant receivable	(221)
Prepaid expenses and other current assets	3,948	(5,103)
Accounts payable	5,693	4,259
Accrued expenses	(1,087)	289
Derivative liability		(1,174)
Lease liability	(42)
Licenses payable	(1,000)	800
Net cash used in operating activities	(22,001)	(48,514)
Cash flows (used in) provided by financing activities
Payment on convertible notes	(5,487)
Proceeds from issuance of common stock and warrants	15,569
Proceeds from issuance of common stock in at-the-market offering	68	457
Payment of deferred offering costs		(273)
Payment for repurchase of common stock	(1,195)
Proceeds from exercise of options		8
Proceeds from sales of common stock under ESPP	97	99
Net cash (used in) provided by financing activities	9,052	291
Net (decrease) increase in cash	(12,949)	(48,223)
Cash, beginning of period	15,533	78,734
Cash, end of period	2,584	30,511
Supplemental disclosure of cash flow information:
Cash paid for interest	316	11
Non-cash investing and financing activities:
Fair value of warrants issued	17,415
Fair value of warrants issued in extinguishment of convertible notes	3,247
Increase in principal in extinguishment of convertible notes	4,882
Issuance of common stock for license payable		840
Deferred offering costs, accrued but not paid	145	$ 32
Issunce of common stock for cashless exercise	2,000
Issunce of common stock for modification of convertible debt	1,010
Issuance of common stock for pincipal payments on convertible notes	3,498
Issuance of common stock for interest payments on convertible notes	$ 431

Organization and Description of

Organization and Description of Business	9 Months Ended
	Sep. 30, 2023
Organization and Description of Business
Organization and Description of Business	1. Organization and Description of Business Seelos Therapeutics, Inc. (together with its subsidiaries, the “Company”) is a clinical-stage biopharmaceutical company focused on achieving efficient development of products that address significant unmet needs in Central Nervous System (“CNS”) disorders and other rare disorders. The Company’s lead programs are SLS-002 for the potential treatment of acute suicidal ideation and behavior in patients with major depressive disorder (“ASIB in MDD”) and SLS-005 for the potential treatment of Amyotrophic Lateral Sclerosis (“ALS”) and Spinocerebellar Ataxia (“SCA”). SLS-005 for the potential treatment of Sanfilippo Syndrome currently requires additional natural history data, which is being considered. Additionally, the Company is developing several preclinical programs, most of which have well-defined mechanisms of action, including: SLS-004, SLS-006 and SLS-007 for the potential treatment of Parkinson’s Disease (“PD”). On March 29, 2023, the Company announced that it plans to focus the majority of its resources on the Phase II study of SLS-002 for ASIB in MDD and the fully enrolled Phase II/III study of SLS-005 in ALS. The Company further announced that it has temporarily paused additional enrollment of patients in the SLS-005-302 study in SCA. Patients already enrolled will continue in the study and data will continue to be collected in order to make decisions for resuming enrollment in the future. The Company also announced that it is pausing all non-essential preclinical work.

Liquidity and Going Concern

Liquidity and Going Concern	9 Months Ended
	Sep. 30, 2023
Liquidity and Going Concern
Liquidity and Going Concern	2. Liquidity and Going Concern The accompanying condensed consolidated unaudited financial statements have been prepared assuming the Company will continue to operate as a going concern, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from uncertainty related to its ability to continue as a going concern. The Company has generated limited revenues, has incurred operating losses since inception, and expects to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of September 30, 2023, the Company had $2.6 On September 21, 2023, the Company entered into a Securities Purchase Agreement (the “September 2023 Securities Purchase Agreement”) with certain purchasers identified on the signature pages thereto (the “Purchasers”), pursuant to which, on September 25, 2023, the Company issued and sold 15,000,000 shares (the “Shares”) of its common stock and accompanying common stock warrants to purchase up to 10,010,010 shares of common stock (the “September 2023 Warrants”) in a registered direct offering (the “September 2023 RDO”). The Shares and the September 2023 Warrants were offered by the Company pursuant to its shelf registration statement on Form S-3 (File No. 333-251356) filed with the Securities and Exchange Commission (the “SEC”) on December 15, 2020, as amended by Amendment No. 1 thereto filed with the SEC on December 22, 2020 and declared effective on December 23, 2020 (as amended, the “Registration Statement”). The exercise price of the September 2023 Warrants was $0.325 per share, subject to adjustment as provided therein, and the September 2023 Warrants were immediately exercisable upon issuance and were to expire on the date that is five years following the original issuance date. In addition, the September 2023 Warrants contained an alternative “cashless exercise” provision whereby a September 2023 Warrant could be exchanged cashlessly for shares of common stock at the rate of 0.999 of a share of common stock per full share otherwise issuable upon a cash exercise. The combined purchase price for one Share and accompanying September 2023 Warrant to purchase shares of common stock was $0.30. The aggregate net proceeds from the September 2023 RDO, after deducting the fees payable to financial advisors and other estimated offering expenses, were approximately $4.1 million (see Note 6). The fair value of the September 2023 Warrants upon issuance was $1.9 million and such amount was included within warrant liabilities, at fair value on the condensed consolidated balance sheets. On September 26, 2023 and September 27, 2023, the holders of the September 2023 Warrants elected to cashlessly exchange their September 2023 Warrants in full for an aggregate issuance of 2,222,222 and 7,777,778 shares of common stock, respectively, and, thereafter, no September 2023 Warrants remain outstanding. As a result of the exercise of the September 2023 Warrants, the Company recognized a $100,000 expense within change in fair value of warrant liabilities on the condensed consolidated statement of operations. On March 10, 2023, the Company entered into a Securities Purchase Agreement (the “March 2023 Securities Purchase Agreement”) with a life sciences-focused investment fund (the “Investor”), pursuant to which, on March 14, 2023, the Company issued and sold an aggregate of 12,059,298 shares of common stock, pre-funded warrants exercisable for an aggregate of 9,340,702 shares of common stock (the “March 2023 Pre-Funded Warrants”) and accompanying common warrants exercisable for an aggregate of 26,750,000 shares of common stock in a registered direct offering (the “March 2023 RDO”), resulting in total net proceeds of $10.4 million, after deducting financial advisor fees and other offering expenses (see Note 6). On May 19, 2023, the Company entered into Amendment No. 1 to the March 2023 Securities Purchase Agreement (the “2023 Purchase Agreement Amendment”), pursuant to which the Investor agreed to, among other things, waive certain restrictions on issuing and registering shares of common stock contained within the March 2023 Securities Purchase Agreement to permit the Company to make the May Through September Payments (as defined below) in a combination of cash and shares of common stock as contemplated in the 2021 Note Amendment (as defined below). In consideration for entering into the 2023 Purchase Agreement Amendment, on May 19, 2023, the Company issued to the Investor warrants to purchase up to an aggregate of 4,000,000 shares of common stock. The fair value of these warrants upon issuance was $3.2 million and such amount is included within loss on extinguishment of debt on the condensed consolidated statement of operations. On July 3, 2023 and September 19, 2023, the holders of the March 2023 Pre-Funded Warrants exercised their March 2023 Warrants on a cashless basis for an issuance of an aggregate of 2,719,999 and 6,611,820 shares of common stock, respectively, and, thereafter, no March 2023 Pre-Funded Warrants remain outstanding. On May 12, 2022, the Company entered into an Open Market Sale Agreement SM three On November 21, 2022, the Company received a written notice from Nasdaq indicating that, for the last thirty consecutive business days, the bid price for its common stock had closed below the minimum $1.00 per share requirement for continued listing on the Nasdaq Capital Market under Nasdaq Listing Rule 5550(a)(2) (“Rule 5550(a)(2)”). In accordance with Nasdaq Listing Rule 5810(c)(3)(A), the Company was provided an initial period of 180 calendar days, or until May 22, 2023, to regain compliance. On May 23, 2023, Nasdaq provided a notice to the Company that the Company has not regained compliance with Rule 5550(a)(2) and was not eligible for a second 180 On November 1, 2023, the Company received an additional written notice from Nasdaq indicating that, for the last thirty consecutive business days, the bid price for its common stock had closed below the minimum $1.00 per share requirement for continued listing on the Nasdaq Capital Market under Rule 5550(a)(2). In accordance with Nasdaq Listing Rule 5810(c)(3)(A), the Company has been provided an initial period of 180 calendar days, or until April 29, 2024, to regain compliance. The Nasdaq staff will provide written confirmation that the Company has achieved compliance with Rule 5550(a)(2) if at any time before April 29, 2024, the bid price of the Company’s common stock closes at $1.00 per share or more for a minimum of ten consecutive business days. In addition, on November 2, 2023, the Company received an additional written notice from Nasdaq indicating that, for the last thirty-two consecutive business days, the market value of the Company’s listed securities has been below the minimum requirement of $35 million for continued listing on the Nasdaq Capital Market under Nasdaq Listing Rule 5550(b)(2) (“Rule 5550(b)(2)”). In accordance with Nasdaq Listing Rule 5810(c)(3)(C), the Company has been provided a period of 180 Pursuant to the Registration Statement, the Company may offer from time to time any combination of debt securities, common and preferred stock, and warrants. As of September 30, 2023, the Company had approximately $59.4 million available under the Registration Statement (inclusive of the $49.5 million that remained allocated to sales of shares pursuant to the Sale Agreement as of such date). The Company also has the ability to raise funds through other means, such as through the filing of a registration statement on Form S-1 or in private placements. The rules and regulations of the SEC or any other regulatory agencies may restrict the Company’s ability to conduct certain types of financing activities or may affect the timing of and amounts it can raise by undertaking such activities. The Company evaluated whether there are any conditions and events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year beyond the filing of this Quarterly Report on Form 10-Q. Based on such evaluation and the Company’s current plans (including the ongoing clinical programs for SLS-002, SLS-005, and other product candidates), which are subject to change, management believes that the Company’s existing cash and cash equivalents as of September 30, 2023 are not sufficient to satisfy its operating cash needs and that there is substantial doubt about its ability to continue as a going concern for the year after the filing of this Quarterly Report on Form 10-Q. The Company’s future liquidity and capital funding requirements will depend on numerous factors, including: ● its ability to raise additional funds to finance its operations; ● its ability to maintain compliance with the listing requirements of the Nasdaq Capital Market; ● the outcome, costs and timing of clinical trial results for the Company’s current or future product candidates; ● potential litigation expenses; ● the emergence and effect of competing or complementary products or product candidates; ● its ability to maintain, expand and defend the scope of its intellectual property portfolio, including the amount and timing of any payments the Company may be required to make, or that it may receive, in connection with the licensing, filing, prosecution, defense and enforcement of any patents or other intellectual property rights; ● its ability to retain its current employees and the need and ability to hire additional management and scientific and medical personnel; ● the terms and timing of any collaborative, licensing, or other arrangements that it has or may establish; ● the trading price of its common stock; and ● its ability to increase the number of authorized shares as may be required to facilitate future financing events. The Company may raise substantial additional funds, and if it does so, it may do so through one or more of the following: issuance of additional debt or equity and/or the completion of a licensing or other commercial transaction for one or more of the Company’s product candidates. If the Company is unable to maintain sufficient financial resources, its business, financial condition, and results of operations will be materially and adversely affected. This could affect future development and business activities and potential future clinical studies and/or other future ventures. Failure to obtain additional equity or debt financing will have a material, adverse impact on the Company’s business operations. There can be no assurance that the Company will be able to obtain the needed financing on acceptable terms or at all. Additionally, equity or convertible debt financings will likely have a dilutive effect on the holdings of the Company’s existing stockholders.

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
Significant Accounting Policies
Significant Accounting Policies	3. Significant Accounting Policies Basis of Presentation The accompanying unaudited interim condensed consolidated financial statements should be read in conjunction with the audited financial statements and notes thereto as of and for the year ended December 31, 2022, included in the Company’s Annual Report on Form 10-K (the “Annual Report”) filed with the SEC on March 10, 2023. The accompanying financial statements have been prepared by the Company in accordance with United States generally accepted accounting principles (“U.S. GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. In the opinion of management, the accompanying unaudited condensed consolidated financial statements for the periods presented reflect all adjustments, consisting of only normal, recurring adjustments, necessary to fairly state the Company’s financial position, results of operations and cash flows. The December 31, 2022 condensed consolidated balance sheet was derived from audited financial statements, but it does not include all U.S. GAAP disclosures. The unaudited condensed consolidated financial statements for the interim periods are not necessarily indicative of results for the full year. The preparation of these unaudited condensed consolidated financial statements requires the Company to make estimates and judgments that affect the amounts reported in the financial statements and the accompanying notes. The Company’s actual results may differ from these estimates under different assumptions or conditions. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. The most significant estimates in the Company’s financial statements relate to the valuation of warrants, valuation of convertible notes payable, and the valuation of stock options. These estimates and assumptions are based on current facts, historical experience and various other factors believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of expenses that are not readily apparent from other sources. Actual results may differ materially and adversely from these estimates. To the extent there are material differences between the estimates and actual results, the Company’s future results of operations will be affected. Fair Value Measurements The Company follows the accounting guidance in the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 820, Fair Value Measurements and Disclosures (“ASC 820”), for its fair value measurements of financial assets and liabilities measured at fair value on a recurring basis. Under this accounting guidance, fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. The accounting guidance requires fair value measurements be classified and disclosed in one of the following three categories: Level 1: Quoted prices in active markets for identical assets or liabilities. Level 2: Observable inputs other than Level 1 prices, for similar assets or liabilities that are directly or indirectly observable in the marketplace. Level 3: Unobservable inputs which are supported by little or no market activity and that are financial instruments whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant judgment or estimation. The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Fair Value Option As permitted under FASB ASC Topic 825, Financial Instruments (“ASC 825”), the Company elected the fair value option to account for its November 2021 and December 2021 convertible notes (collectively, the “2021 Convertible Notes”). In accordance with ASC 825, the Company records these convertible notes at fair value with changes in fair value recorded in the Condensed Consolidated Statement of Operations and Comprehensive Loss. As a result of applying the fair value option, direct costs and fees related to the convertible notes were expensed as incurred and were not deferred. Stock-based Compensation The Company expenses stock-based compensation to employees, non-employees and board members over the requisite service period based on the estimated grant-date fair value of the awards and forfeitures rates. The Company accounts for forfeitures as they occur. Stock-based awards with graded-vesting schedules are recognized on a straight-line basis over the requisite service period for each separately vesting portion of the award. The Company estimates the fair value of stock option grants using the Black-Scholes option pricing model, and the assumptions used in calculating the fair value of stock-based awards represent management’s best estimates and involve inherent uncertainties and the application of management’s judgment. All stock-based compensation costs are recorded in general and administrative or research and development costs in the statements of operations based upon the underlying individual’s role at the Company. Performance share awards are initially valued based on the Company’s closing stock price on the date of grant. The number of performance share awards that vest will be determined based on the achievement of specified performance milestones by the end of the performance period. Compensation expense for performance awards is recognized over the service period and will vary based on remeasurement during the performance period. If achievement of the performance milestone is not probable of achievement during the performance period, compensation expense is reversed. Income (Loss) Per Common Share Basic income (loss) per share is computed by dividing net income (loss) applicable to common stockholders by the weighted average number of shares of common stock outstanding during each period. Diluted loss per share includes the effect, if any, from the potential exercise or conversion of securities, such as convertible debt, warrants, performance-based restricted stock unit awards and stock options that would result in the issuance of incremental shares of common stock. For warrants that are liability-classified, during periods when the impact is dilutive, the Company assumes share settlement of the instruments as of the beginning of the reporting period and adjusts the numerator to remove the change in fair value of the warrant liability and adjusts the denominator to include the dilutive shares calculated using the treasury stock method. The following table sets forth the computation of basic and diluted income (loss) per share (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ ​ 2023 ​ 2022 ​ 2023 ​ 2022 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) attributable to common stockholders - basic ​ $ 10,498 ​ $ (19,604) ​ $ (32,429) $ (54,877) Less: change in fair value of warrant liabilities ​ (27,637) ​ — ​ — ​ — Net income (loss) attributable to common stockholders - diluted ​ $ (17,139) ​ $ (19,604) ​ $ (32,429) $ (54,877) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator: ​ ​ ​ ​ Weighted average common shares outstanding- basic ​ 135,330,494 ​ 106,689,924 ​ 126,672,513 ​ 106,100,413 Effect of dilutive securities ​ 12,808,227 ​ — ​ — ​ — Weighted average common shares outstanding - diluted ​ 148,138,721 ​ 106,689,924 ​ 126,672,513 ​ 106,100,413 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) per share attributable to common stockholders - basic ​ $ 0.08 ​ $ (0.18) ​ $ (0.26) $ (0.52) Net income (loss) per share attributable to common stockholders - diluted ​ $ (0.12) ​ $ (0.18) ​ $ (0.26) $ (0.52) ​ The following potentially dilutive securities outstanding for the three and nine months ended September 30, 2023 and 2022 have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months ​ Nine Months ​ ​ Ended September 30, ​ Ended September 30, ​ 2023 2022 2023 2022 Outstanding stock options ​ 15,342 ​ 10,400 ​ 15,342 ​ 10,400 Outstanding warrants 1,222 2,545 32,274 2,545 Convertible debt 2,806 3,704 2,806 3,704 ​ 19,370 16,649 50,422 16,649 ​ Amounts in the table reflect the common stock equivalents of the noted instruments. Recent Accounting Pronouncements In August 2020, the FASB issued Accounting Standards Update (“ASU”) No. 2020-06: Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”). This standard simplifies the accounting for convertible debt instruments by removing the separation models for convertible debt with a cash conversion feature, as well as convertible instruments with a beneficial conversion feature. As a result, entities will account for a convertible debt instrument wholly as debt, unless certain other conditions are met. The elimination of these models will reduce non-cash interest expense for entities that have issued a convertible instrument that was within the scope of those models before the adoption of ASU 2020-06. Additionally, ASU 2020-06 requires the application of the if-converted method for calculating diluted earnings per share and precludes the use of the treasury stock method for certain debt instruments. The provisions of ASU 2020-06 are applicable for the Company beginning after January 1, 2024, with early adoption permitted no earlier than fiscal years beginning after December 15, 2020, and an entity should adopt the provisions at the beginning of its annual fiscal year. The Company has decided to early adopt the provisions of ASU 2020-06 as of January 1, 2023, and the Company does not expect the adoption of ASU 2020-06 to have an impact on its consolidated financial statements and related disclosures. In June 2022, the FASB issued ASU No. 2022-03: ASC Subtopic 820 - Value Measurement of Equity Securities Subject to Contractual Sale Restrictions (“ASU 2022-03”). ASU 2022-03 amends ASC 820 to clarify that a contractual sales restriction is not considered in measuring an equity security at fair value and to introduce new disclosure requirements for equity securities subject to contractual sale restrictions that are measured at fair value. ASU 2022-03 applies to both holders and issuers of equity and equity-linked securities measured at fair value. The amendments in ASU 2022-03 are effective for the Company for fiscal years beginning after December 15, 2023, and the interim periods within those fiscal years. Early adoption is permitted for both interim and annual financial statements that have not yet been issued or made available for issuance. The Company is evaluating the impact of this pronouncement on its consolidated financial statements and related disclosures.

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2023
Fair Value Measurement
Fair Value Measurement	​ 4. Fair Value Measurement The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values. There were no transfers between fair value measurement levels during the three and nine months ended September 30, 2023. The Company’s financial assets and liabilities measured at fair value at September 30, 2023 and December 31, 2022 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ as of September 30, 2023 ​ (Level 1) (Level 2) (Level 3) Total Assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 2,584 ​ $ — ​ $ — ​ $ 2,584 Liabilities: ​ ​ ​ ​ ​ Convertible notes payable, at fair value ​ $ — ​ $ — ​ $ 16,876 ​ $ 16,876 Warrant liabilities, at fair value ​ — ​ — ​ 4,063 ​ 4,063 ​ ​ $ — ​ $ — ​ $ 20,939 ​ $ 20,939 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ as of December 31, 2022 ​ (Level 1) (Level 2) (Level 3) Total Assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 15,533 ​ $ — ​ $ — ​ $ 15,533 Liabilities: ​ ​ ​ ​ Convertible notes payable, at fair value ​ $ — ​ $ — ​ $ 20,049 ​ $ 20,049 Warrant liabilities, at fair value ​ — ​ — ​ 132 ​ 132 ​ ​ $ — ​ $ — ​ $ 20,181 ​ $ 20,181 ​ The fair value of the Company’s money market funds is based on quoted active market prices for the funds and is determined using the market approach. The Company measures the 2021 Convertible Notes and warrant liabilities at fair value based on significant inputs not observable in the market, which causes them to be classified as a Level 3 measurement within the fair value hierarchy. These valuations use assumptions and estimates the Company believes would be made by a market participant in making the same valuation. The Company assesses these assumptions and estimates on an on-going basis as additional data impacting the assumptions and estimates are obtained. Changes in the fair value of the convertible notes payable and warrant liabilities related to updated assumptions and estimates are recognized within the Condensed Consolidated Statements of Operations and Comprehensive Loss. The fair value of the 2021 Convertible Notes and warrant liabilities may change significantly as additional data is obtained, impacting the Company’s assumptions regarding probabilities of outcomes used to estimate the fair value of the liabilities. The estimates of fair value may not be indicative of the amounts that could be realized in a current market exchange. Accordingly, the use of different market assumptions and/or different valuation techniques may have a material effect on the estimated fair value amounts, and such changes could materially impact the Company’s results of operations in future periods. 2021 Convertible Notes The 2021 Convertible Notes are valued using a Monte Carlo simulation model. The following assumptions were used in determining the fair value of the 2021 Convertible Notes as of September 30, 2023 and December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2023 December 31, 2022 Risk-free interest rate ​ 5.41 % ​ 4.24 % Volatility ​ 125 % ​ 105 % Dividend yield ​ — % ​ — % Contractual term (years) ​ 1.1 ​ 1.9 ​ Stock price ​ $ 0.18 ​ $ 0.68 ​ ​ Warrant Liabilities The common stock warrant liabilities are recorded at fair value using the Black-Scholes option pricing model. The following assumptions were used in determining the fair value of the warrant liabilities valued using the Black-Scholes option pricing model as of September 30, 2023 and December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2023 December 31, 2022 Risk-free interest rate ​ 4.60% - 5.56 % ​ 4.71 % Volatility ​ 121.0% - 125.0 % ​ 91.90 % Dividend yield ​ — % ​ — % Expected term (years) ​ 0.32 - 5.14 ​ 1.07 ​ Weighted-average fair value ​ $ 0.03 - 0.13 ​ $ 0.44 ​ ​ The following table is a reconciliation for the common stock warrant liabilities and convertible notes measured at fair value using Level 3 unobservable inputs (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Convertible notes, ​ Warrant liabilities Derivative liability at fair value Balance as of December 31, 2021 ​ $ 424 ​ $ 1,174 ​ $ 18,920 Settlement of derivative liability ​ — ​ (1,174) ​ — Principal payment of convertible notes, at fair value ​ ​ — ​ ​ — ​ ​ (1,888) Issuance of derivative liability ​ ​ — ​ ​ — ​ ​ — Change in fair value measurement of derivative liability ​ — ​ — ​ — Change in fair value measurement of convertible notes ​ — ​ — ​ 3,017 Change in fair value measurement of warrant liability ​ (292) ​ — ​ — Balance as of December 31, 2022 ​ $ 132 ​ $ — ​ $ 20,049 Principal payment of convertible notes, at fair value ​ — ​ — ​ (8,672) Interest payment of convertible notes, at fair value ​ — ​ — ​ (745) Issuance of convertible note ​ ​ — ​ ​ — ​ ​ 4,882 Loss on extinguishment of debt ​ ​ — ​ ​ — ​ ​ 13 Change in fair value measurement of convertible notes ​ ​ — ​ ​ — ​ ​ 1,349 Fair value of warrants issued ​ ​ 20,661 ​ ​ — ​ ​ — Warrant exercised ​ ​ (2,000) ​ ​ — ​ ​ — Change in fair value measurement of warrant liability ​ (14,730) ​ — ​ — Balance as of September 30, 2023 ​ $ 4,063 ​ $ — ​ $ 16,876 ​ For the three and nine months ended September 30, 2023, and the year ended December 31, 2022, the changes in fair value of the convertible notes and warrant liability primarily resulted from the volatility of the Company’s common stock and the change in risk-free interest rates.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	9 Months Ended
	Sep. 30, 2023
Prepaid Expenses and Other Current Assets.
Prepaid Expenses and Other Current Assets	5. Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets are comprised of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2023 2022 Prepaid insurance ​ $ 249 ​ $ 104 Prepaid clinical costs ​ 3,081 ​ 6,837 Other ​ 53 ​ 200 Prepaid expenses and other current assets ​ $ 3,383 ​ $ 7,141 ​

Common Stock Offerings

Common Stock Offerings	9 Months Ended
	Sep. 30, 2023
Common Stock Offerings
Common Stock Offerings	6. March 2023 Registered Direct Offering On March 10, 2023, the Company entered into the March 2023 Securities Purchase Agreement, pursuant to which the Company issued and sold an aggregate of 12,059,298 shares of common stock, pre-funded warrants exercisable for an aggregate of 9,340,702 shares of common stock (the “March 2023 Pre-Funded Warrants”) and accompanying common stock warrants exercisable for an aggregate of 26,750,000 shares of common stock (“March 2023 Common Warrants” and together with the March 2023 Pre-Funded Warrants, the “March 2023 Warrants”) in the March 2023 RDO, resulting in total net proceeds of $10.4 million, after deducting financial advisor fees and other offering expenses. The securities were offered by the Company pursuant to the Registration Statement. The March 2023 Pre-Funded Warrants were exercisable immediately upon issuance and had an exercise price of $0.001 per share of common stock. During the quarter ended September 30, 2023, all of the Pre-Funded Warrants were exercised in full on a cashless basis, and no March 2023 Pre-Funded Warrants remain outstanding. The March 2023 Common Warrants have an exercise price of $0.60 per share of common stock, became exercisable on September 11, 2023, and will expire on September 10, 2028. The combined purchase price for one share and one accompanying March 2023 Common Warrant to purchase 1.25 shares of common stock in the March 2023 RDO was $0.525 and the combined purchase price for one March 2023 Pre-Funded Warrant and one accompanying March 2023 Common Warrant to purchase 1.25 shares of common stock in the March 2023 RDO was $0.524. The closing of the March 2023 RDO occurred on March 14, 2023. On May 19, 2023, the Company entered into the 2023 Purchase Agreement Amendment pursuant to which the Investor agreed to, among other things, waive certain restrictions on issuing and registering shares of common stock contained within the 2023 Securities Purchase Agreement to permit the Company to make the May Through September Payments (as defined below) in a combination of cash and shares of common stock as contemplated in the 2021 Note Amendment (as defined below). In consideration for entering into the 2023 Purchase Agreement Amendment, on May 19, 2023, the Company issued to the Investor warrants to purchase up to an aggregate of 4,000,000 shares of common stock. The exercise price of the May 2023 Warrants is $1.06 per share, subject to adjustment as provided therein, and the May 2023 Warrants will be exercisable beginning on November 19, 2023 and will expire on November 20, 2028. The fair value of these warrants upon issuance was $3.2 million and such amount is included within loss on extinguishment of debt on the condensed consolidated statement of operations. September 2023 Registered Direct Offering On September 21, 2023, The Company entered into the September 2023 Securities Purchase Agreement with certain Purchasers, pursuant to which the Company agreed to issue and sell 15,000,000 shares (the “Shares”) of its common stock and accompanying common stock warrants to purchase up to 10,010,010 shares of common stock in a registered direct offering. The Shares and the September 2023 Warrants were offered by the Company pursuant to its Registration Statement. The exercise price of the September 2023 Warrants was $0.325 per share, subject to adjustment as provided therein, and the September 2023 Warrants were immediately exercisable upon issuance and expire on the date that is five years following the original issuance date. In addition, the September 2023 Warrants contained an alternative “cashless exercise” provision whereby a September 2023 Warrant could be exchanged cashlessly for shares of common stock at the rate of 0.999 of a share of common stock per full share otherwise issuable upon a cash exercise. The fair value of the September 2023 Warrants upon issuance was $1.9 million and such amount was included within warrant liabilities, at fair value on the condensed consolidated balance sheets. On September 26, 2023 and September 27, 2023, the holders of the September 2023 Warrants elected to cashlessly exchange their September 2023 Warrants in full for an aggregate issuance of 2,222,222 and 7,777,778 shares of common stock, respectively, and, thereafter, no September 2023 Warrants remain outstanding. As a result of the exercise of the September 2023 Warrants the Company recognized a $100,000 expense within change in fair value of warrant liabilities on the condensed consolidated statement of operations.

License Agreements

License Agreements	9 Months Ended
	Sep. 30, 2023
License Agreements
License Agreements	7. License Agreements Specific information pertaining to each of the Company’s significant license agreements is discussed in its audited financial statements included in the Annual Reports on Form 10-K for the years ended December 31, 2022 and 2021, including their nature and purpose, the significant rights and obligations of the parties, and specific accounting policy elections. The following represents updates for the three and nine months ended September 30, 2023, if applicable, to the Company’s significant license agreements: Acquisition of Assets from Phoenixus AG f/k/a Vyera Pharmaceuticals, AG and Turing Pharmaceuticals AG (“Vyera”) On April 8, 2022, Seelos Corporation (“STI”), a wholly-owned subsidiary of the Company, and Vyera, entered into an amendment (the “Amendment”) to the Asset Purchase Agreement by and between STI and Vyera, dated March 6, 2018 (as amended by a first amendment thereto entered into on May 18, 2018, a second amendment thereto entered into on December 31, 2018, a third amendment thereto entered into on October 15, 2019 and a fourth amendment thereto entered into on February 15, 2021, the “Vyera Purchase Agreement”). Pursuant to the Vyera Purchase Agreement, STI acquired the assets and liabilities of Vyera related to a product candidate currently referred to as SLS-002 (intranasal ketamine) (the “Vyera Assets”) and agreed, among other things, to make certain development and commercialization milestone payments and royalty payments related to the Vyera Assets (the “Milestone and Royalty Payment Obligations”) and further agreed that in the event that the Company sold, directly or indirectly, all or substantially all of the Vyera Assets to a third party, then the Company would pay Vyera an amount equal to 4% of the net proceeds actually received by the Company as an upfront payment in such sale (the “Change of Control Payment Obligation”). Pursuant to the Vyera Purchase Agreement, as amended by the Amendment, STI agreed to (i) make a cash payment to Vyera in the aggregate amount of $4.0 million on or before April 8, 2022 (the “Cash Payment”); (ii) issue to Vyera on or before April 11, 2022, 500,000 shares of the Company’s common stock (the “Initial Shares”); (iii) issue to Vyera on or before July 11, 2022, an additional 500,000 shares of the Company’s common stock (as adjusted for stock splits, stock dividends, combinations, recapitalizations and the like) (the “July 2022 Shares”); and (iv) issue to Vyera on or before January 11, 2023, an additional number of shares of the Company’s common stock equal to $1.0 million divided by the volume weighted average closing price of the Company’s common stock for the ten consecutive trading days ending on the fifth trading day prior to the applicable date of issuance of the shares of the Company’s common stock (the “January 2023 Shares”, and together with the Cash Payment, the Initial Shares and the July 2022 Shares, the “Final Payments”). In consideration for the Final Payments, all of STI’s contingent payment obligations under the Vyera Purchase Agreement, including the Milestone and Royalty Payment Obligations and the Change of Control Payment Obligation, as well as all commercialization covenants of STI under the Vyera Purchase Agreement, will terminate in full upon the date that all of the Final Payments have been made. On December 22, 2022, the Company entered into a Share Repurchase Agreement (the “Repurchase Agreement”) with Vyera, pursuant to which the Company agreed to repurchase the Initial Shares and the July 2022 Shares previously issued to Vyera for an aggregate purchase price of $1.2 million in January 2023. The Company paid the $4.0 million Cash Payment and issued the Initial Shares to Vyera in April 2022. The Company issued the July 2022 Shares to Vyera in July 2022, and subsequently agreed to repurchase the Initial Shares and the July 2022 Shares in January 2023 pursuant to the Repurchase Agreement on December 22, 2022. The Company recognized $5.8 million in research and development expense during the nine months ended September 30, 2022 related to the Amendment, which consisted of the initial cash payment of $4.0 million and $0.8 million for the Initial Shares and the July 2022 Shares, which were measured at their grant-date fair value. The Company also recognized a liability of $1.0 million related to the January 2023 Shares within accrued licenses payable. The Company recognized a liability of $1.2 million related to the Repurchase Agreement, as well as $0.5 million in research and development expense for the premium paid for the repurchased shares. On January 3, 2023, the Company paid $1.2 million in cash to Vyera under the Repurchase Agreement to repurchase the Initial Shares and the July 2022 Shares. On January 10, 2023, STI entered into Amendment No. 6 to the Vyera Purchase Agreement (“Amendment No. 6”) with Vyera, pursuant to which, STI agreed to make two cash payments to Vyera of $500,000 each on January 31, 2023 and February 28, 2023, in lieu of issuing the January 2023 Shares to Vyera. The Company paid the $500,000 cash payments on each of January 31, 2023 and February 28, 2023 in satisfaction of all Final Payments under the Vyera Purchase Agreement. Acquisition of License from Stuart Weg, MD On August 29, 2019, the Company entered into an amended and restated exclusive license agreement with Stuart Weg, M.D. (the “Weg License Agreement”), pursuant to which the Company was granted an exclusive worldwide license to certain intellectual property and regulatory materials related to SLS-002. Under the terms of the Weg License Agreement, the Company paid an upfront license fee of $75,000 upon execution of the agreement. The Company agreed to pay additional consideration to Dr. Weg as follows: (i) $0.1 million on January 2, 2020, (ii) $0.125 million on January 2, 2021, and (iii) in the event the FDA has not approved a New Drug Application for a product containing ketamine in any dosage on or before December 31, 2021, $0.2 million on January 2, 2022. The Company paid the required $0.1 million on January 2, 2020, $0.125 million on January 2, 2021 and $0.2 million on January 2, 2022. The remaining potential regulatory and commercial milestones are not yet considered probable, and no other milestone payments have been accrued as of September 30, 2023.

Accrued Expenses

Accrued Expenses	9 Months Ended
	Sep. 30, 2023
Accrued Expenses
Accrued Expenses	8. Accrued Expenses Accrued expenses are comprised of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2023 2022 Professional fees ​ $ 195 ​ $ 278 Personnel related ​ 1,121 ​ 1,288 Outside research and development services ​ 4,909 ​ 5,627 Insurance ​ ​ 72 ​ ​ — Other ​ 43 ​ 89 Accrued expenses, net ​ $ 6,340 ​ $ 7,282 ​

Debt

Debt	9 Months Ended
	Sep. 30, 2023
Debt
Debt	9. Debt Convertible Notes November 2021 and December 2021 Convertible Notes and Private Placement On November 23, 2021, the Company entered into a Securities Purchase Agreement (the “2021 Lind Securities Purchase Agreement”) with Lind Global Asset Management V, LLC (“Lind”) pursuant to which, among other things, on November 23, 2021 (the “Closing Date”), the Company issued and sold to Lind, in a private placement transaction (the “Private Placement”), in exchange for the payment by Lind of $20.0 million, (i) a convertible promissory note (as amended from time to time, the “2021 Note”) in an initial aggregate principal amount of $22.0 million (the “Principal Amount”), which will bear no interest until the first anniversary of the issuance of the 2021 Note and will thereafter bear interest at a rate of 5% per annum, and mature on November 23, 2024 (the “Maturity Date”), and (ii) 534,759 shares of Company common stock. Commencing August 23, 2022, and from time to time and before the Maturity Date, Lind has the option to convert any portion of the then-outstanding Principal Amount of the 2021 Note into shares of common stock at a price per share of $6.00, subject to adjustment for stock splits, reverse stock splits, stock dividends and similar transactions (the “Conversion Price”). Commencing August 23, 2022, the Company has the right to prepay, in whole or in part (exercisable by the Company at any time or from time to time prior to the Maturity Date), up to the full remaining Principal Amount of the 2021 Note with no penalty; however, if the Company exercises such prepayment right, Lind will have the option to convert up to thirty-three and one-third percent ( 33 Subject to certain exceptions, the Company will be required to direct proceeds from any subsequent debt financings (including subordinated debt, convertible debt or mandatorily redeemable preferred stock but other than purchase money debt or capital lease obligations or other indebtedness incurred in the ordinary course of business) to repay the 2021 Note, unless waived by Lind in advance. Beginning on November 23, 2022, the 2021 Note amortizes in twenty-four five 20 On May 19, 2023, the Company entered into Amendment No. 3 (the “2021 Note Amendment”) to the 2021 Note, pursuant to which the Company and Lind agreed, among other things, that: (A) effective as of May 19, 2023, the outstanding Principal Amount was increased by $1,250,000 to $17,750,000 and the fair value of $1.3 million is included within loss on extinguishment of debt on the condensed consolidated statement of operations; (B) the Company shall not be required to maintain any minimum balance of cash or cash equivalents with one or more financial institutions prior to September 15, 2023, and that it shall thereafter be required to maintain an aggregate minimum balance equal to 50% of the then outstanding principal amount under the 2021 Note or more in cash or cash equivalents with one or more financial institutions (the “Minimum Cash Condition”); (C) effective as of September 15, 2023, upon an Event of Default (as defined in the 2021 Note), Lind shall have the right to convert the then outstanding principal amount of the 2021 Note into shares of common stock at the lower of (x) the then-current conversion price (which is currently $6.00 per share, subject to adjustment in certain circumstances as described in the 2021 Note) and (y) 85% of the average of the five 20 five 20 On September 13, 2023, pursuant to an Irrevocable Waiver, Lind agreed to unilaterally, unconditionally, irrevocably and permanently waive its right to assert that any Event of Default (as defined in the 2021 Note) would be deemed to occur pursuant to the 2021 Note or that the Company breached the 2021 Note if the Company failed to satisfy the Minimum Cash Condition at any time on or after September 15, 2023 and through and including September 30, 2023 (the “Waiver Period”), in each case solely in connection with the Company’s failure to satisfy the Minimum Cash Condition during the Waiver Period. On September 21, 2023, and concurrently with the execution of the September 2023 Securities Purchase Agreement, the Company entered into a letter agreement with Lind related to the 2021 Note (the “Letter Agreement”), pursuant to which the Company and Lind agreed that, in lieu of, and in full satisfaction of, both the monthly payment that would otherwise have been due under the 2021 Note on September 23, 2023 and the interest payment that would otherwise have been due on September 29, 2023, (i) the Company would, by no later than September 29, 2023, pay to Lind cash in an aggregate amount equal to $686,564 and (ii) Lind would have the right, at any time and from time to time, between the closing date of the September 2023 RDO and the date that is 45 days after such closing date, to convert the remaining amount of the monthly payment that would have otherwise been due on September 24, 2023 in the aggregate amount of up to $400,000 into shares of common stock at the lower of (a) the then-current Conversion Price (as defined in the 2021 Note, which is currently $6.00 per share) and (b) 85% of the average of the five On September 30, 2023, the Company and Lind entered into an Amendment No. 4 to the 2021 Note and Amendment to Letter Agreement (the “Amendment”), pursuant to which the Company and Lind agreed, among other things, that: (A) effective as of September 30, 2023, the outstanding principal amount of the 2021 Note was increased by $3,631,528 to $16,837,084; (B) commencing October 1, 2023, the 2021 Note will bear interest at an annual rate of 12% per annum; (C) the Company shall not be required to maintain any minimum balance of cash or cash equivalents with one or more financial institutions prior to March 28, 2024, and that it shall thereafter be required to maintain an aggregate minimum balance equal to 50% of the then outstanding principal amount under the 2021 Note or more in cash or cash equivalents with one or more financial institutions; (D) subject to certain exceptions, if the Company issues securities for cash consideration, the Company will be required utilize 25% of the net cash proceeds to repay the 2021 Note unless Lind elects not to be repaid; (E) Lind will, through March 28, 2024, forebear from exercising any right to assert or claim a Material Adverse Effect (as defined in the 2021 Note) has occurred as a result of any event, occurrence, fact, condition or change that occurred on or prior to September 30, 2023; (F) the Company shall use its reasonable best efforts to seek, at a special or annual meeting of the stockholders of the Company to be scheduled to be held no later than January 16, 2024, the stockholder approval as contemplated by Nasdaq Listing Rule 5635(d) with respect to the approval of the issuance of shares of Common Stock in excess of the limitation on the number of shares issuable under the 2021 Note as set forth in the 2021 Note and 2021 Lind Securities Purchase Agreement; and (G) subject to certain exceptions, as long as the 2021 Note remains outstanding, Lind will have the right to participate in any equity or debt financing by the Company in an amount equal to the lesser of 50% of the securities to be offered and $5,000,000 of the securities to be offered in such financing. The Amendment provides that the number of shares issuable pursuant to the Subsequent Conversion Right was limited to an aggregate of 1,877,084 shares of Common Stock. As a result of the modification, the Company recognized a loss on extinguishment of the debt, recorded as a component of the change in fair value of convertible notes on the condensed consolidated statements of operations. The Company will continue to account for the 2021 Note using the fair value election. The Company issued 1,877,084 shares of its common stock in connection with Lind’s exercise of the Subsequent Conversion Right on October 5, 2023. On December 2, 2021, the Company entered into two separate securities purchase agreements with certain accredited investors on substantially the same terms as the 2021 Lind Securities Purchase Agreement, pursuant to which the Company sold, in private placement transactions, in exchange for the payment by the accredited investors of an aggregate of $201,534, (i) convertible promissory notes in an aggregate principal amount of $221,688, which did not bear interest and mature on December 2, 2024 (the “December 2021 Notes”), and (ii) an aggregate of 5,388 shares of its common stock. These notes had substantially the same terms as the 2021 Note. On February 22, 2023, the December 2021 Notes were repaid in full, and the Company recognized a loss on extinguishment of debt of $13,000 during the nine months ended September 30, 2023. During the year ended December 31, 2021, the Company received aggregate gross proceeds of $20.2 million from the convertible note offerings. The Company elected to account for these notes under the fair value option. At time of issuance, the Company recorded a liability of $19.2 million, which was determined to be the fair value at time of issuance. As of December 31, 2022 and 2021, the Company recognized a total convertible note liability of $20.0 million and $18.9 million, respectively. During the year ended December 31, 2022 and 2021, the Company recognized $3.0 million loss and $0.2 million gain, respectively, on changes in fair value of convertible notes. During the three and nine months ended September 30, 2023, the Company recognized losses of $0.8 million and $1.3 million, respectively, on changes in fair values of convertible notes. During the three and nine months ended September 30, 2022, the Company recognized losses of $0.1 million and $0.3 million, respectively, on changes in fair value of convertible notes. During the three and nine months ended September 30, 2023, the Company recognized losses of $3.6 million and $9.1 million, respectively, on loss on extinguishment of debt on the condensed consolidated statement of operations. During the nine months ended September 30, 2023, the Company made principal payments of $ The 2021 Note contains certain restrictive covenants and event of default provisions, including a covenant requiring the Company to maintain an aggregate minimum balance equal to 50% of the then outstanding principal amount under the 2021 Note or more in cash and cash equivalents commencing on March 28, 2024. As of September 30, 2023, the outstanding principal amount of the 2021 Note was $16.8 million. Based on the Company’s current operating plan and its cash balance as of September 30, 2023, the Company does not expect be able to maintain the minimum cash balance required to satisfy the minimum cash covenant if it does not raise additional financing by March 28, 2024. If the Company is unable to cure such default within fifteen days from its occurrence or otherwise obtain a waiver from Lind or amend the terms of the 2021 Note, the Company would trigger a default under the 2021 Note. If the Company is not able to comply or regain compliance with any of the covenants in, or otherwise trigger a default under, the 2021 Note, Lind could declare the 2021 Note immediately due and payable, which would require the Company to pay 120% of the outstanding principal amount of the 2021 Note and would have a material adverse effect on its liquidity, financial condition, operating results, business and prospects, and could cause the price of the Company’s common stock to decline. In addition, since the borrowings under the 2021 Note are secured by a first priority lien on the Company’s assets, Lind would be able to foreclose on the Company’s assets if it does not cure any default or pay any amounts due and payable under the 2021 Note. In addition, upon an Event of Default (as defined in the 2021 Note), Lind shall have the right to convert the then outstanding principal amount of the 2021 Note into shares of the Company’s common stock at the lower of (x) the then-current conversion price (which is currently $6.00 per share, subject to adjustment in certain circumstances as described in the 2021 Note) and (y) 85% of the average of the five

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2023
Stockholders' Equity
Stockholders' Equity	10. Stockholders’ Equity Preferred Stock The Company is authorized to issue 10,000,000 shares of preferred stock, par value $0.001. No shares of preferred stock were outstanding as of September 30, 2023 or December 31, 2022. Common Stock The Company has authorized 480,000,000 and 240,000,000 shares of common stock as of September 30, 2023 and December 31, 2022, respectively. Each share of common stock is entitled to one voting right. Common stock owners are entitled to dividends when funds are legally available and declared by the Board of Directors. Warrants September 2023 Warrants On September 21, 2023, the Company entered into the September 2023 Securities Purchase Agreement, pursuant to which the Company issued and sold an aggregate of 15,000,000 shares of its common stock and the September 2023 Warrants exercisable for an aggregate of 10,010,010 shares of its common stock in the September 2023 RDO. The September 2023 Warrants were exercisable immediately upon issuance and had an exercise price per share equal to $0.325 per share. In addition, the September 2023 Warrants contain an alternative “cashless exercise” provision whereby a September 2023 Warrant may be exchanged cashlessly for shares of common stock at a rate of 0.999 of a share of common stock per full share otherwise issuable upon a cash exercise. During the nine months ended September 30, 2023, September 2023 Warrants to purchase approximately 10.0 million shares of common stock were cashlessly exchanged and no September 2023 Warrants remain outstanding. May 2023 Warrants On May 19, 2023, the Company entered into the 2023 Purchase Agreement Amendment, pursuant to which the Investor agreed to, among other things, waive certain restrictions on issuing and registering shares of common stock contained within the 2023 Securities Purchase Agreement to permit the Company to make the May Through September Payments in a combination of cash and shares of common stock as contemplated in the 2021 Note Amendment. In consideration for entering into the 2023 Purchase Agreement Amendment, on May 19, 2023, the Company issued to the Investor warrants to purchase up to an aggregate of 4,000,000 shares of common stock (the “May 2023 Warrants”). The exercise price of the May 2023 Warrants is $1.06 per share, subject to adjustment as provided therein, and the May 2023 Warrants will be exercisable beginning on November 19, 2023 and will expire on November 20, 2028. As of September 30, 2023, May 2023 Warrants to purchase 4.0 million shares of common stock remain outstanding at an exercise price of $1.06 per share. March 2023 Warrants On March 10, 2023, the Company entered into a securities purchase agreement with a life sciences-focused investment fund pursuant to which the Company issued and sold an aggregate of 12,059,298 shares of common stock, the March 2023 Pre-Funded Warrants exercisable for an aggregate of 9,340,702 shares of its common stock and the accompanying March 2023 Common Warrants exercisable for an aggregate of 26,750,000 shares of common stock in a registered direct offering. The March 2023 Pre-Funded Warrants were exercisable immediately upon issuance and had an exercise price per share equal to $0.001. The March 2023 Common Warrants have an exercise price per share equal to $0.60. The March 2023 Common Warrants became exercisable beginning on September 11, 2023 and will expire on September 10, 2028. During the nine months ended September 30, 2023, March 2023 Pre-Funded Warrants to purchase approximately 9.3 million shares of common stock were exercised on a cashless basis. As of September 30, 2023, March 2023 Pre-Funded Warrants to purchase 9.3 million shares of common stock all have been exercised on a cashless basis and March 2023 Common Warrants to purchase 26.8 million shares of common stock remain outstanding at an exercise price of $0.60 per share. September 2020 Warrants On September 4, 2020, the Company entered into a securities purchase agreement with certain institutional investors pursuant to which the Company issued and sold an aggregate of 8,865,000 shares of common stock in a registered direct offering and issued warrants to purchase up to 6,648,750 shares of common stock in a concurrent private placement (the “September 2020 Warrants”). The September 2020 Warrants are exercisable for 6,648,750 shares of common stock at an exercise price per share equal to $0.84. The September 2020 Warrants became exercisable beginning on March 9, 2021 and will expire on March 9, 2026. During the nine months ended September 30, 2023 and 2022, no September 2020 Warrants were exercised. As of September 30, 2023, September 2020 Warrants exercisable for 1.0 million shares of common stock remain outstanding at an exercise price of $0.84 per share. August 2019 Warrants On August 23, 2019, the Company entered into a securities purchase agreement with certain institutional investors pursuant to which the Company issued and sold an aggregate of 4,475,000 shares of common stock in a registered direct offering and issued warrants to purchase up to 2,237,500 shares of common stock in a concurrent private placement (the “August 2019 Warrants”). The August 2019 Warrants were initially exercisable for 2,237,500 shares of common stock at an exercise price per share equal to $1.78. The August 2019 Warrants became exercisable beginning on February 27, 2020 and will expire on August 28, 2023. During the nine months ended September 30, 2023 and 2022, no August 2019 Warrants were exercised. As of September 30, 2023, August 2019 Warrants exercisable for 900,000 shares of common stock remain outstanding at an exercise price of $1.78 per share. Series A Warrants On January 24, 2019, STI and the Company closed a private placement with certain accredited investors pursuant to which, among other things, the Company issued warrants representing the right to acquire 1,463,519 shares of common stock (the “Series A Warrants”). The Series A Warrants were initially exercisable for 1,463,519 shares of common stock at an exercise price per share equal to $4.15, which was adjusted several times pursuant to the terms thereof to 3,629,023 shares of common stock at an exercise price per share equal to $0.2734 per share. The most recent adjustment to the exercise price (from $0.2957 to $0.2734 per share) occurred during the three months ended September 30, 2023, as a result of the announcement of the September 2023 RDO. The Series A Warrants were immediately exercisable upon issuance and will expire on January 31, 2024. During the nine months ended September 30, 2023 and 2022, no Series A Warrants were exercised. As of September 30, 2023, Series A Warrants exercisable for 0.3 million shares of common stock remain outstanding at an exercise price of $0.2734 per share. The exercise price of the Series A Warrants was adjusted in September 2023 due to the adjustment provisions in the Series A Warrants as a result of the September 2023 RDO. A summary of warrant activity during the nine months ended September 30, 2023 is as follows (share amounts in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ Weighted- ​ Average ​ ​ ​ ​ Average ​ Remaining ​ ​ ​ ​ Exercise ​ Contractual Life ​ Warrants Price (in years) Outstanding as of December 31, 2022 2,545 ​ $ 2.78 1.7 Issued 50,101 ​ $ 0.41 ​ Exercised (19,351) ​ $ 0.00 ​ Cancelled (1,021) ​ $ 3.38 ​ Outstanding as of September 30, 2023 32,274 ​ $ 0.74 4.8 Exercisable as of September 30, 2023 32,274 ​ $ 0.74 4.8 ​ The September 2023 Warrants, the May 2023 Warrants, the March 2023 Common Warrants, the March 2023 Pre-Funded Warrants and the Series A Warrants were recognized as a liability at their fair value upon issuance. The warrant liability is remeasured to the then fair value prior to their exercise or at period end for warrants that are unexercised, and the gain or loss recognized in earnings during the period.

Stock-based Compensation

Stock-based Compensation	9 Months Ended
	Sep. 30, 2023
Stock-based Compensation
Stock-based Compensation	11. Stock-based Compensation The Company has the Seelos Therapeutics, Inc. Amended and Restated 2012 Stock Long Term Incentive Plan (the “2012 Plan”), which provides for the issuance of incentive and non-incentive stock options, restricted and unrestricted stock awards, stock unit awards and stock appreciation rights. Options and restricted stock units granted generally vest over a period of one On May 15, 2020, the Company’s stockholders approved the Company’s 2020 Employee Stock Purchase Plan (the “ESPP”), whereby qualified employees are allowed to purchase limited amounts of the Company’s common stock at the lesser of 85% of the market price at the beginning or end of the offering period. The stockholders have authorized an initial amount of 1.0 million shares for purchase by employees under the ESPP. The ESPP provides that an additional number of shares will automatically be added annually to the shares authorized for issuance under the ESPP on January 1st of each year commencing on January 1, 2021 and ending on (and including) January 1, 2030, which amount shall be equal to the lesser of (i) 1% of the number of shares of the Company’s common stock issued and outstanding on the immediately preceding December 31, and (ii) a number of shares of common stock set by the Company’s Board of Directors or the Compensation Committee of the Board of Directors (the “Compensation Committee”) of the Company on or prior to each such January 1. On January 1, 2023, the Company added 1,063,421 shares for purchase by employees under the ESPP. During the nine months ended September 30, 2023, the Company sold 149,122 shares of common stock under the ESPP. The compensation costs are calculated as the fair value of the 15% discount from market price and were approximately $27,000 for the nine months ended September 30, 2023. On July 28, 2019, the Compensation Committee adopted the Seelos Therapeutics, Inc. 2019 Inducement Plan (the “2019 Inducement Plan”), which became effective on August 12, 2019. The 2019 Inducement Plan provides for the grant of equity-based awards in the form of stock options, stock appreciation rights, restricted stock, unrestricted stock, stock units, including restricted stock units, performance units and cash awards, solely to prospective employees of the Company or an affiliate of the Company provided that certain criteria are met. Awards under the 2019 Inducement Plan may only be granted to an individual, as a material inducement to such individual to enter into employment with the Company, who (i) has not previously been an employee or director of the Company or (ii) is rehired following a bona fide period of non-employment with the Company. The maximum number of shares available for grant under the 2019 Inducement Plan is 1,000,000 shares of the Company’s common stock. The 2019 Inducement Plan is administered by the Compensation Committee and expires on August 12, 2029. Stock options During the nine months ended September 30, 2023, the Company granted 1,517,585 incentive stock options and 2,959,625 non-qualified stock options to employees with a weighted average exercise price per share of $0.69 and a 10-year term, subject to the terms and conditions of the 2012 Plan above. The stock options are subject to time vesting requirements. The stock options granted to employees vest 25% on the first anniversary of the grant and monthly thereafter over the next three years. During the nine months ended September 30, 2023, the Company also granted 338,135 non-qualified stock options to employees who elected to forgo a portion of their cash bonus for stock options with a weighted average exercise price per share of $0.69 and a 10-year term, subject to the terms and conditions of the 2012 Plan above. The stock options are not subject to time vesting requirements and are fully vested upon the date of grant. During the nine months ended September 30, 2023, the Company also granted 200,000 non-qualified stock options to non-employee directors with a weighted average exercise price per share of $0.81 and a 10-year term, subject to the terms and conditions of the 2012 Plan above. The stock options granted to non-employee directors vest monthly over the 12 months following the grant. The fair value of stock option grants is estimated on the date of grant using the Black-Scholes option-pricing model. The Company was historically a private company and lacked sufficient company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on a weighted average blend of the historical volatility of a publicly traded set of peer companies, as well as its own historical volatility. Additionally, due to an insufficient history with respect to stock option activity and post-vesting cancellations, the expected term assumption for employee grants is based on a permitted simplified method, which is based on the vesting period and contractual term for each tranche of awards. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect for time periods approximately equal to the expected term of the award. Expected dividend yield is zero based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future. During the nine months ended September 30, 2023, no stock options were exercised, and 73,000 options were forfeited. During the nine months ended September 30, 2022, 6,250 stock options were exercised and no options were forfeited. The following assumptions were used in determining the fair value of the stock options granted during the nine months ended September 30, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ September 30, 2023 September 30, 2022 Risk-free interest rate ​ 3.5%-3.9% ​ 1.6%-3.4% Volatility ​ 116%-119% ​ 111%-113% Dividend yield ​ —% ​ —% Expected term (years) ​ 5-6 ​ 5-6 Weighted-average fair value $ 0.60 $ 1.22 ​ A summary of stock option activity during the nine months ended September 30, 2023 is as follows (share amounts in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ ​ ​ Weighted- ​ Average ​ Total ​ ​ ​ ​ Average ​ Remaining ​ Aggregate ​ ​ Stock ​ Exercise ​ Contractual ​ Intrinsic ​ Options Price Life (in years) Value Outstanding as of December 31, 2022 10,400 ​ $ 2.26 ​ ​ ​ Granted 5,015 ​ 0.70 ​ ​ ​ Exercised ​ — ​ ​ — ​ ​ ​ ​ ​ Forfeited (47) ​ 1.91 ​ ​ ​ Expired ​ (26) ​ ​ 87.60 ​ ​ ​ ​ ​ Outstanding as of September 30, 2023 15,342 ​ $ 1.60 8.0 ​ $ — Vested and expected to vest as of September 30, 2023 15,342 ​ $ 1.60 8.0 ​ $ — Exercisable as of September 30, 2023 7,495 ​ $ 1.97 7.2 ​ $ — ​ As of September 30, 2023, unrecognized stock-option compensation expense of $7.5 million is expected to be realized over a weighted-average period of 2.07 years. Performance Stock Award During the year ended December 31, 2021, the Company’s Board of Directors awarded a performance stock unit award to the Company’s Chief Executive Officer for 2,400,000 shares of common stock, with a grant date fair value of $4.31 per unit. Vesting of this award was subject to the Company achieving certain performance criteria established at the grant date and the individual fulfilling a service condition (continued employment). As of December 31, 2021, all performance stock unit awards were unvested and three of the five performance conditions had been satisfied. The Company recognized stock-based compensation related to this award of $4.9 million during the fourth quarter of 2021, which was recorded in general and administrative expense. In 2022, the Company and its Chief Executive Officer entered into an agreement to cancel the performance stock unit award for no consideration. In connection with the cancellation of the award, no replacement awards were granted or authorized. At the time of cancellation, the Company recognized the remaining compensation expense of the three achieved milestones of $1.3 million. The two remaining milestones were not deemed probable of achievement at the time of cancellation, and no compensation cost related to these milestones was recognized. The following table summarizes the total stock-based compensation expense resulting from share-based awards recorded in the Company’s condensed consolidated statements of operations (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ September 30, ​ September 30, ​ 2023 2022 2023 2022 Research and development ​ $ 267 ​ $ 261 ​ $ 770 ​ $ 721 General and administrative ​ 707 ​ 712 ​ 2,254 ​ 3,445 ​ ​ $ 974 ​ $ 973 ​ $ 3,024 ​ $ 4,166 ​

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies
Commitments and Contingencies	12. Commitments and Contingencies Leases In March 2021, the Company entered into an eighteen-month office space rental agreement for its headquarters at 300 Park Avenue, New York, NY, which ended in September 2022. In October 2022, the Company entered into a new eighteen-month office space rental agreement for its existing space, which provides for a base rent starting at approximately $4,500 per month subject to periodic increases. Under the new office space rental agreement in October 2022, in exchange for the new operating lease liability, the Company recognized a right-of-use asset of approximately $86,000. As of September 30, 2023, the weighted-average remaining lease term of the operating lease was 6 months, and the weighted-average discount rate was 8.0%. As of September 30, 2023, future minimum lease payments for the Company’s operating lease with a non-cancelable term is as follows (in thousands): ​ ​ ​ ​ ​ ​ Operating ​ ​ Leases Year Ended December 31, 2023 ​ $ 16 Year Ended December 31, 2024 ​ 16 Total ​ 32 Less present value discount ​ (2) Operating lease liabilities ​ $ 30 ​ For the nine months ended September 30, 2023 and 2022, rent expense totaled $47,000 and $42,000, respectively. Contractual Commitments The Company has entered into long-term agreements with certain manufacturers and suppliers that require it to make contractual payment to these organizations. The Company expects to enter into additional collaborative research, contract research, manufacturing, and supplier agreements in the future, which may require up-front payments and long-term commitments of cash. Litigation As of September 30, 2023, there was no material litigation against or involving the Company.

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Significant Accounting Policies
Basis of Presentation	Basis of Presentation The accompanying unaudited interim condensed consolidated financial statements should be read in conjunction with the audited financial statements and notes thereto as of and for the year ended December 31, 2022, included in the Company’s Annual Report on Form 10-K (the “Annual Report”) filed with the SEC on March 10, 2023. The accompanying financial statements have been prepared by the Company in accordance with United States generally accepted accounting principles (“U.S. GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. In the opinion of management, the accompanying unaudited condensed consolidated financial statements for the periods presented reflect all adjustments, consisting of only normal, recurring adjustments, necessary to fairly state the Company’s financial position, results of operations and cash flows. The December 31, 2022 condensed consolidated balance sheet was derived from audited financial statements, but it does not include all U.S. GAAP disclosures. The unaudited condensed consolidated financial statements for the interim periods are not necessarily indicative of results for the full year. The preparation of these unaudited condensed consolidated financial statements requires the Company to make estimates and judgments that affect the amounts reported in the financial statements and the accompanying notes. The Company’s actual results may differ from these estimates under different assumptions or conditions.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. The most significant estimates in the Company’s financial statements relate to the valuation of warrants, valuation of convertible notes payable, and the valuation of stock options. These estimates and assumptions are based on current facts, historical experience and various other factors believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of expenses that are not readily apparent from other sources. Actual results may differ materially and adversely from these estimates. To the extent there are material differences between the estimates and actual results, the Company’s future results of operations will be affected.
Fair Value Measurements	Fair Value Measurements The Company follows the accounting guidance in the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 820, Fair Value Measurements and Disclosures (“ASC 820”), for its fair value measurements of financial assets and liabilities measured at fair value on a recurring basis. Under this accounting guidance, fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. The accounting guidance requires fair value measurements be classified and disclosed in one of the following three categories: Level 1: Quoted prices in active markets for identical assets or liabilities. Level 2: Observable inputs other than Level 1 prices, for similar assets or liabilities that are directly or indirectly observable in the marketplace. Level 3: Unobservable inputs which are supported by little or no market activity and that are financial instruments whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant judgment or estimation. The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement.
Fair Value Option	Fair Value Option As permitted under FASB ASC Topic 825, Financial Instruments (“ASC 825”), the Company elected the fair value option to account for its November 2021 and December 2021 convertible notes (collectively, the “2021 Convertible Notes”). In accordance with ASC 825, the Company records these convertible notes at fair value with changes in fair value recorded in the Condensed Consolidated Statement of Operations and Comprehensive Loss. As a result of applying the fair value option, direct costs and fees related to the convertible notes were expensed as incurred and were not deferred.
Stock-based Compensation	Stock-based Compensation The Company expenses stock-based compensation to employees, non-employees and board members over the requisite service period based on the estimated grant-date fair value of the awards and forfeitures rates. The Company accounts for forfeitures as they occur. Stock-based awards with graded-vesting schedules are recognized on a straight-line basis over the requisite service period for each separately vesting portion of the award. The Company estimates the fair value of stock option grants using the Black-Scholes option pricing model, and the assumptions used in calculating the fair value of stock-based awards represent management’s best estimates and involve inherent uncertainties and the application of management’s judgment. All stock-based compensation costs are recorded in general and administrative or research and development costs in the statements of operations based upon the underlying individual’s role at the Company. Performance share awards are initially valued based on the Company’s closing stock price on the date of grant. The number of performance share awards that vest will be determined based on the achievement of specified performance milestones by the end of the performance period. Compensation expense for performance awards is recognized over the service period and will vary based on remeasurement during the performance period. If achievement of the performance milestone is not probable of achievement during the performance period, compensation expense is reversed.
Income (Loss) Per Common Share	Income (Loss) Per Common Share Basic income (loss) per share is computed by dividing net income (loss) applicable to common stockholders by the weighted average number of shares of common stock outstanding during each period. Diluted loss per share includes the effect, if any, from the potential exercise or conversion of securities, such as convertible debt, warrants, performance-based restricted stock unit awards and stock options that would result in the issuance of incremental shares of common stock. For warrants that are liability-classified, during periods when the impact is dilutive, the Company assumes share settlement of the instruments as of the beginning of the reporting period and adjusts the numerator to remove the change in fair value of the warrant liability and adjusts the denominator to include the dilutive shares calculated using the treasury stock method. The following table sets forth the computation of basic and diluted income (loss) per share (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ ​ 2023 ​ 2022 ​ 2023 ​ 2022 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) attributable to common stockholders - basic ​ $ 10,498 ​ $ (19,604) ​ $ (32,429) $ (54,877) Less: change in fair value of warrant liabilities ​ (27,637) ​ — ​ — ​ — Net income (loss) attributable to common stockholders - diluted ​ $ (17,139) ​ $ (19,604) ​ $ (32,429) $ (54,877) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator: ​ ​ ​ ​ Weighted average common shares outstanding- basic ​ 135,330,494 ​ 106,689,924 ​ 126,672,513 ​ 106,100,413 Effect of dilutive securities ​ 12,808,227 ​ — ​ — ​ — Weighted average common shares outstanding - diluted ​ 148,138,721 ​ 106,689,924 ​ 126,672,513 ​ 106,100,413 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) per share attributable to common stockholders - basic ​ $ 0.08 ​ $ (0.18) ​ $ (0.26) $ (0.52) Net income (loss) per share attributable to common stockholders - diluted ​ $ (0.12) ​ $ (0.18) ​ $ (0.26) $ (0.52) ​ The following potentially dilutive securities outstanding for the three and nine months ended September 30, 2023 and 2022 have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months ​ Nine Months ​ ​ Ended September 30, ​ Ended September 30, ​ 2023 2022 2023 2022 Outstanding stock options ​ 15,342 ​ 10,400 ​ 15,342 ​ 10,400 Outstanding warrants 1,222 2,545 32,274 2,545 Convertible debt 2,806 3,704 2,806 3,704 ​ 19,370 16,649 50,422 16,649 ​ Amounts in the table reflect the common stock equivalents of the noted instruments.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2020, the FASB issued Accounting Standards Update (“ASU”) No. 2020-06: Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”). This standard simplifies the accounting for convertible debt instruments by removing the separation models for convertible debt with a cash conversion feature, as well as convertible instruments with a beneficial conversion feature. As a result, entities will account for a convertible debt instrument wholly as debt, unless certain other conditions are met. The elimination of these models will reduce non-cash interest expense for entities that have issued a convertible instrument that was within the scope of those models before the adoption of ASU 2020-06. Additionally, ASU 2020-06 requires the application of the if-converted method for calculating diluted earnings per share and precludes the use of the treasury stock method for certain debt instruments. The provisions of ASU 2020-06 are applicable for the Company beginning after January 1, 2024, with early adoption permitted no earlier than fiscal years beginning after December 15, 2020, and an entity should adopt the provisions at the beginning of its annual fiscal year. The Company has decided to early adopt the provisions of ASU 2020-06 as of January 1, 2023, and the Company does not expect the adoption of ASU 2020-06 to have an impact on its consolidated financial statements and related disclosures. In June 2022, the FASB issued ASU No. 2022-03: ASC Subtopic 820 - Value Measurement of Equity Securities Subject to Contractual Sale Restrictions (“ASU 2022-03”). ASU 2022-03 amends ASC 820 to clarify that a contractual sales restriction is not considered in measuring an equity security at fair value and to introduce new disclosure requirements for equity securities subject to contractual sale restrictions that are measured at fair value. ASU 2022-03 applies to both holders and issuers of equity and equity-linked securities measured at fair value. The amendments in ASU 2022-03 are effective for the Company for fiscal years beginning after December 15, 2023, and the interim periods within those fiscal years. Early adoption is permitted for both interim and annual financial statements that have not yet been issued or made available for issuance. The Company is evaluating the impact of this pronouncement on its consolidated financial statements and related disclosures.

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2023
Significant Accounting Policies
Schedule of computation of basic and diluted income (loss) per share	The following table sets forth the computation of basic and diluted income (loss) per share (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ ​ 2023 ​ 2022 ​ 2023 ​ 2022 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) attributable to common stockholders - basic ​ $ 10,498 ​ $ (19,604) ​ $ (32,429) $ (54,877) Less: change in fair value of warrant liabilities ​ (27,637) ​ — ​ — ​ — Net income (loss) attributable to common stockholders - diluted ​ $ (17,139) ​ $ (19,604) ​ $ (32,429) $ (54,877) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator: ​ ​ ​ ​ Weighted average common shares outstanding- basic ​ 135,330,494 ​ 106,689,924 ​ 126,672,513 ​ 106,100,413 Effect of dilutive securities ​ 12,808,227 ​ — ​ — ​ — Weighted average common shares outstanding - diluted ​ 148,138,721 ​ 106,689,924 ​ 126,672,513 ​ 106,100,413 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income (loss) per share attributable to common stockholders - basic ​ $ 0.08 ​ $ (0.18) ​ $ (0.26) $ (0.52) Net income (loss) per share attributable to common stockholders - diluted ​ $ (0.12) ​ $ (0.18) ​ $ (0.26) $ (0.52)
Schedule of antidilutive securities excluded from computation of diluted weighted average shares outstanding	The following potentially dilutive securities outstanding for the three and nine months ended September 30, 2023 and 2022 have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months ​ Nine Months ​ ​ Ended September 30, ​ Ended September 30, ​ 2023 2022 2023 2022 Outstanding stock options ​ 15,342 ​ 10,400 ​ 15,342 ​ 10,400 Outstanding warrants 1,222 2,545 32,274 2,545 Convertible debt 2,806 3,704 2,806 3,704 ​ 19,370 16,649 50,422 16,649

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2023
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Schedule of Fair Value Hierarchy Assets and Liabilities	The Company’s financial assets and liabilities measured at fair value at September 30, 2023 and December 31, 2022 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ as of September 30, 2023 ​ (Level 1) (Level 2) (Level 3) Total Assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 2,584 ​ $ — ​ $ — ​ $ 2,584 Liabilities: ​ ​ ​ ​ ​ Convertible notes payable, at fair value ​ $ — ​ $ — ​ $ 16,876 ​ $ 16,876 Warrant liabilities, at fair value ​ — ​ — ​ 4,063 ​ 4,063 ​ ​ $ — ​ $ — ​ $ 20,939 ​ $ 20,939 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ as of December 31, 2022 ​ (Level 1) (Level 2) (Level 3) Total Assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 15,533 ​ $ — ​ $ — ​ $ 15,533 Liabilities: ​ ​ ​ ​ Convertible notes payable, at fair value ​ $ — ​ $ — ​ $ 20,049 ​ $ 20,049 Warrant liabilities, at fair value ​ — ​ — ​ 132 ​ 132 ​ ​ $ — ​ $ — ​ $ 20,181 ​ $ 20,181
Schedule of Fair Value Level 3 Reconciliation	The following table is a reconciliation for the common stock warrant liabilities and convertible notes measured at fair value using Level 3 unobservable inputs (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Convertible notes, ​ Warrant liabilities Derivative liability at fair value Balance as of December 31, 2021 ​ $ 424 ​ $ 1,174 ​ $ 18,920 Settlement of derivative liability ​ — ​ (1,174) ​ — Principal payment of convertible notes, at fair value ​ ​ — ​ ​ — ​ ​ (1,888) Issuance of derivative liability ​ ​ — ​ ​ — ​ ​ — Change in fair value measurement of derivative liability ​ — ​ — ​ — Change in fair value measurement of convertible notes ​ — ​ — ​ 3,017 Change in fair value measurement of warrant liability ​ (292) ​ — ​ — Balance as of December 31, 2022 ​ $ 132 ​ $ — ​ $ 20,049 Principal payment of convertible notes, at fair value ​ — ​ — ​ (8,672) Interest payment of convertible notes, at fair value ​ — ​ — ​ (745) Issuance of convertible note ​ ​ — ​ ​ — ​ ​ 4,882 Loss on extinguishment of debt ​ ​ — ​ ​ — ​ ​ 13 Change in fair value measurement of convertible notes ​ ​ — ​ ​ — ​ ​ 1,349 Fair value of warrants issued ​ ​ 20,661 ​ ​ — ​ ​ — Warrant exercised ​ ​ (2,000) ​ ​ — ​ ​ — Change in fair value measurement of warrant liability ​ (14,730) ​ — ​ — Balance as of September 30, 2023 ​ $ 4,063 ​ $ — ​ $ 16,876
Long-Term Debt
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Schedule of Fair Value Measurements Warrant Valuation Assumptions	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2023 December 31, 2022 Risk-free interest rate ​ 5.41 % ​ 4.24 % Volatility ​ 125 % ​ 105 % Dividend yield ​ — % ​ — % Contractual term (years) ​ 1.1 ​ 1.9 ​ Stock price ​ $ 0.18 ​ $ 0.68 ​
Outstanding warrants
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Schedule of Fair Value Measurements Warrant Valuation Assumptions	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2023 December 31, 2022 Risk-free interest rate ​ 4.60% - 5.56 % ​ 4.71 % Volatility ​ 121.0% - 125.0 % ​ 91.90 % Dividend yield ​ — % ​ — % Expected term (years) ​ 0.32 - 5.14 ​ 1.07 ​ Weighted-average fair value ​ $ 0.03 - 0.13 ​ $ 0.44 ​

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	9 Months Ended
	Sep. 30, 2023
Prepaid Expenses and Other Current Assets.
Schedule prepaid expenses and other current assets	Prepaid expenses and other current assets are comprised of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2023 2022 Prepaid insurance ​ $ 249 ​ $ 104 Prepaid clinical costs ​ 3,081 ​ 6,837 Other ​ 53 ​ 200 Prepaid expenses and other current assets ​ $ 3,383 ​ $ 7,141 ​

Accrued Expenses (Tables)

Accrued Expenses (Tables)	9 Months Ended
	Sep. 30, 2023
Accrued Expenses
Schedule of accrued expenses	Accrued expenses are comprised of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2023 2022 Professional fees ​ $ 195 ​ $ 278 Personnel related ​ 1,121 ​ 1,288 Outside research and development services ​ 4,909 ​ 5,627 Insurance ​ ​ 72 ​ ​ — Other ​ 43 ​ 89 Accrued expenses, net ​ $ 6,340 ​ $ 7,282 ​

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2023
Stockholders' Equity
Schedule of warrant activity	A summary of warrant activity during the nine months ended September 30, 2023 is as follows (share amounts in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ Weighted- ​ Average ​ ​ ​ ​ Average ​ Remaining ​ ​ ​ ​ Exercise ​ Contractual Life ​ Warrants Price (in years) Outstanding as of December 31, 2022 2,545 ​ $ 2.78 1.7 Issued 50,101 ​ $ 0.41 ​ Exercised (19,351) ​ $ 0.00 ​ Cancelled (1,021) ​ $ 3.38 ​ Outstanding as of September 30, 2023 32,274 ​ $ 0.74 4.8 Exercisable as of September 30, 2023 32,274 ​ $ 0.74 4.8

Stock-based Compensation (Table

Stock-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2023
Stock-based Compensation
Schedule of fair value of stock options granted	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ September 30, 2023 September 30, 2022 Risk-free interest rate ​ 3.5%-3.9% ​ 1.6%-3.4% Volatility ​ 116%-119% ​ 111%-113% Dividend yield ​ —% ​ —% Expected term (years) ​ 5-6 ​ 5-6 Weighted-average fair value $ 0.60 $ 1.22
Schedule of stock option activity	A summary of stock option activity during the nine months ended September 30, 2023 is as follows (share amounts in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ ​ ​ Weighted- ​ Average ​ Total ​ ​ ​ ​ Average ​ Remaining ​ Aggregate ​ ​ Stock ​ Exercise ​ Contractual ​ Intrinsic ​ Options Price Life (in years) Value Outstanding as of December 31, 2022 10,400 ​ $ 2.26 ​ ​ ​ Granted 5,015 ​ 0.70 ​ ​ ​ Exercised ​ — ​ ​ — ​ ​ ​ ​ ​ Forfeited (47) ​ 1.91 ​ ​ ​ Expired ​ (26) ​ ​ 87.60 ​ ​ ​ ​ ​ Outstanding as of September 30, 2023 15,342 ​ $ 1.60 8.0 ​ $ — Vested and expected to vest as of September 30, 2023 15,342 ​ $ 1.60 8.0 ​ $ — Exercisable as of September 30, 2023 7,495 ​ $ 1.97 7.2 ​ $ —
Schedule of stock-based compensation expense resulting from share based awards	The following table summarizes the total stock-based compensation expense resulting from share-based awards recorded in the Company’s condensed consolidated statements of operations (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ September 30, ​ September 30, ​ 2023 2022 2023 2022 Research and development ​ $ 267 ​ $ 261 ​ $ 770 ​ $ 721 General and administrative ​ 707 ​ 712 ​ 2,254 ​ 3,445 ​ ​ $ 974 ​ $ 973 ​ $ 3,024 ​ $ 4,166 ​

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies
Schedule of future minimum operating lease payments	​ ​ ​ ​ ​ ​ Operating ​ ​ Leases Year Ended December 31, 2023 ​ $ 16 Year Ended December 31, 2024 ​ 16 Total ​ 32 Less present value discount ​ (2) Operating lease liabilities ​ $ 30

Liquidity and Going Concern (De

Liquidity and Going Concern (Details) - USD ($)

3 Months Ended

9 Months Ended

Nov. 02, 2023

Nov. 01, 2023

Sep. 27, 2023

Sep. 26, 2023

Sep. 25, 2023

Sep. 21, 2023

Sep. 19, 2023

Jul. 03, 2023

May 23, 2023

May 22, 2023

May 19, 2023

Mar. 14, 2023

Mar. 10, 2023

May 12, 2022

Sep. 30, 2023

Sep. 30, 2023

Sep. 30, 2022

Mar. 31, 2023

Dec. 31, 2022

Nov. 21, 2022

Jan. 24, 2019

Liquidity and Going Concern

Cash

$ 2,584,000

$ 2,584,000

$ 15,533,000

Accumulated deficit

(247,173,000)

(247,173,000)

(214,744,000)

Number of warrants to purchase common stock

9,340,702

1,463,519

Exercise price of warrants

$ 4.15

Warrant liabilities, at fair value

4,063,000

4,063,000

$ 132,000

Change in fair value of warrant liability

(27,637,000)

$ (14,730,000)

$ (192,000)

Period to effect issuance of common stock involving variable rate transaction

3 years

Threshold consecutive trading days considered for volume weighted average price per share

3 days

Minimum requirement of listed securities for the market value

$ 35,000,000

Market value for the common stock closes at the minimum requirement

$ 35,000,000

Threshold consecutive trading days considered for bid price

180 days

Secondary number of calendar days to not regain common stock price compliance

180 days

180 days

Value of shares available under registration statement

59,400,000

$ 59,400,000

Value of shares that remained allocated to sales of shares pursuant to sales agreement

$ 49,500,000

$ 49,500,000

Subsequent events

Liquidity and Going Concern

Threshold consecutive trading days considered for bid price

180 days

Secondary number of calendar days to not regain common stock price compliance

180 days

Minimum

Liquidity and Going Concern

Price per share

$ 1

$ 1

Minimum | Subsequent events

Liquidity and Going Concern

Price per share

$ 1

Maximum

Liquidity and Going Concern

Price per share

$ 1

September 2023 Warrants

Liquidity and Going Concern

Number of shares issued and sold

15,000,000

March 2023 Pre-Funded Warrants

Liquidity and Going Concern

Shares issuable upon exercise of warrants

26,750,000

2023 Securities Purchase Agreement

Liquidity and Going Concern

Number of shares issued and sold

12,059,298

12,059,298

75,768

Aggregate net proceeds

$ 10,400,000

$ 10,400,000

Aggregate future offering amount

$ 50,000,000

Period to effect issuance of common stock involving variable rate transaction in case of at the market offering

1 year

Maximum volume weighted average at price per share

$ 2

2023 Securities Purchase Agreement | Common warrants

Liquidity and Going Concern

Exercise price of warrants

$ 0.60

$ 0.60

$ 0.60

$ 0.60

Shares issuable upon exercise of warrants

26,750,000

26,750,000

Warrants outstanding

26,800,000

26,800,000

2023 Securities Purchase Agreement | March 2023 Pre-Funded Warrants

Liquidity and Going Concern

Exercise price of warrants

$ 9,300,000

$ 9,300,000

$ 0.001

Shares issuable upon exercise of warrants

9,340,702

9,340,702

Number of shares issued as a result of warrants exchanged in cash

6,611,820

2,719,999

9,300,000

Warrants outstanding

0

May 12, 2022 sale agreement

Liquidity and Going Concern

Aggregate net proceeds

$ 68,000,000

Commission rate on gross proceeds of common stock sale

3%

2023 Purchase Agreement Amendment

Liquidity and Going Concern

Shares issuable upon exercise of warrants

4,000,000

Fair value of warrants

$ 3,200,000

September 2023 Securities Purchase Agreement

Liquidity and Going Concern

Number of shares issued and sold

15,000,000

15,000,000

Combined purchase price for one Share and Warrant to purchase shares of common stock

$ 0.30

Aggregate net proceeds

$ 4,100,000

September 2023 Securities Purchase Agreement | September 2023 Warrants

Liquidity and Going Concern

Number of warrants to purchase common stock

10,010,010

10,010,010

Exercise price of warrants

$ 0.325

Term of warrants (in years)

5 years

Share price per common stock if warrants are exchanged in cash

$ 0.999

Warrant liabilities, at fair value

$ 1,900,000

Number of shares issued as a result of warrants exchanged in cash

7,777,778

2,222,222

10,000,000

Warrants outstanding

0

0

0

Change in fair value of warrant liability

$ 100,000

Significant Accounting Polici_4

Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Significant Accounting Policies
Antidilutive securities excluded	19,370,000	16,649,000	50,422,000	16,649,000
Net income (loss) attributable to common stockholders - basic	$ 10,498	$ (19,604)	$ (32,429)	$ (54,877)
Less: change in fair value of warrant liabilities	(27,637)		(14,730)	(192)
Net income (loss) attributable to common stockholders - diluted	$ (17,139)	$ (19,604)	$ (32,429)	$ (54,877)
Weighted-average common shares outstanding basic	135,330,494	106,689,924	126,672,513	106,100,413
Effect of dilutive securities	12,808,227
Weighted average common shares outstanding - diluted	148,138,721	106,689,924	126,672,513	106,100,413
Net income (loss) per share attributable to common stockholders - basic	$ 0.08	$ (0.18)	$ (0.26)	$ (0.52)
Net income (loss) per share attributable to common stockholders - diluted	$ (0.12)	$ (0.18)	$ (0.26)	$ (0.52)
Outstanding stock options
Significant Accounting Policies
Antidilutive securities excluded	15,342,000	10,400,000	15,342,000	10,400,000
Outstanding warrants
Significant Accounting Policies
Antidilutive securities excluded	1,222,000	2,545,000	32,274,000	2,545,000
Convertible debt
Significant Accounting Policies
Antidilutive securities excluded	2,806,000	3,704,000	2,806,000	3,704,000

Fair Value Measurement (Details

Fair Value Measurement (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023
Fair Value Measurement
Transfers between fair value measurement levels	$ 0	$ 0

Fair Value Measurement - Schedu

Fair Value Measurement - Schedule of Fair Value Hierarchy Assets and Liabilities (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Assets:
Cash	$ 2,584	$ 15,533
Liabilities:
Total financial liabilities	20,939	20,181
Convertible notes
Liabilities:
Convertible notes payable, at fair value	16,876	20,049
Outstanding warrants
Liabilities:
Warrant liabilities, at fair value	4,063	132
Level 1
Assets:
Cash	2,584	15,533
Level 3
Liabilities:
Total financial liabilities	20,939	20,181
Level 3 | Convertible notes
Liabilities:
Convertible notes payable, at fair value	16,876	20,049
Level 3 | Outstanding warrants
Liabilities:
Warrant liabilities, at fair value	$ 4,063	$ 132

Fair Value Measurement - Summar

Fair Value Measurement - Summary of Fair Value Measurements Convertible Notes Valuation Assumptions (Details) - Convertible notes - Level 3 - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Fair Value Measurement
Risk-free interest rate (in percent)	5.41%	4.24%
Volatility (in percent)	125%	105%
Contractual term (years)	1 year 1 month 6 days	1 year 10 months 24 days
Stock price	$ 0.18	$ 0.68

Fair Value Measurement - Summ_2

Fair Value Measurement - Summary of Fair Value Measurements Warrant Valuation Assumptions (Details) - Level 3 - Outstanding warrants - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Fair Value Measurement
Risk-free interest rate (in percent)		4.71%
Volatility (in percent)		91.90%
Expected term (years)		1 year 25 days
Weighted-average fair value (in USD per share)		$ 0.44
Minimum
Fair Value Measurement
Risk-free interest rate (in percent)	4.60%
Volatility (in percent)	121%
Expected term (years)	3 months 25 days
Weighted-average fair value (in USD per share)	$ 0.03
Maximum
Fair Value Measurement
Risk-free interest rate (in percent)	5.56%
Volatility (in percent)	125%
Expected term (years)	5 years 1 month 20 days
Weighted-average fair value (in USD per share)	$ 0.13

Fair Value Measurement - Sche_2

Fair Value Measurement - Schedule of Fair Value Level 3 Reconciliation (Details) - Level 3 - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Outstanding warrants
Fair Value Measurement
Balance at beginning	$ 132	$ 424
Principal payment of convertible notes, at fair value	(2,000)
Fair value of warrants issued	20,661
Change in fair value measurement	(14,730)	(292)
Balance at ending	4,063	132
Convertible notes
Fair Value Measurement
Balance at beginning	20,049	18,920
Principal payment of convertible notes, at fair value	(8,672)	(1,888)
Interest payment of convertible notes, at fair value	(745)
Fair value of warrants issued	4,882
Loss on extinguishment of debt	13
Change in fair value measurement	1,349	3,017
Balance at ending	$ 16,876	20,049
Derivative liability
Fair Value Measurement
Balance at beginning		1,174
Settlement of derivative liability		(1,174)
Issuance of derivative liability		$ 1,174

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Prepaid Expenses and Other Current Assets.
Prepaid insurance	$ 249	$ 104
Prepaid clinical costs	3,081	6,837
Other	53	200
Prepaid expenses and other current assets	$ 3,383	$ 7,141

Common Stock Offerings (Details

Common Stock Offerings (Details) - USD ($)										3 Months Ended	9 Months Ended
	Sep. 27, 2023	Sep. 26, 2023	Sep. 25, 2023	Sep. 21, 2023	Sep. 19, 2023	Jul. 03, 2023	May 19, 2023	Mar. 14, 2023	Mar. 10, 2023	Sep. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Mar. 31, 2023	Dec. 31, 2022	Jan. 24, 2019
Common Stock Offerings
Number of warrants to purchase common stock									9,340,702						1,463,519
Exercise price of warrants															$ 4.15
Warrant liabilities, at fair value										$ 4,063,000	$ 4,063,000			$ 132,000
Change in fair value of warrant liability										$ (27,637,000)	$ (14,730,000)	$ (192,000)
2023 Securities Purchase Agreement
Common Stock Offerings
Number of shares issued and sold								12,059,298	12,059,298		75,768
Aggregate net proceeds								$ 10,400,000	$ 10,400,000
2023 Purchase Agreement Amendment
Common Stock Offerings
Fair value of warrants							$ 3,200,000
Shares issuable upon exercise of warrants							4,000,000
September 2023 Securities Purchase Agreement
Common Stock Offerings
Number of shares issued and sold			15,000,000	15,000,000
Aggregate net proceeds				$ 4,100,000
Combined purchase price per share				$ 0.30
Common warrants | 2023 Securities Purchase Agreement
Common Stock Offerings
Exercise price of warrants									$ 0.60	$ 0.60	$ 0.60		$ 0.60
Warrants outstanding										26,800,000	26,800,000
Shares issuable upon exercise of warrants								26,750,000	26,750,000
May 2023 warrants | 2023 Securities Purchase Agreement
Common Stock Offerings
Exercise price of warrants							$ 1.06			$ 1.06	$ 1.06
Warrants outstanding										4,000,000	4,000,000
Shares issuable upon exercise of warrants							4,000,000
September 2023 Warrants
Common Stock Offerings
Number of shares issued and sold				15,000,000
September 2023 Warrants | September 2023 Securities Purchase Agreement
Common Stock Offerings
Number of warrants to purchase common stock			10,010,010	10,010,010
Exercise price of warrants				$ 0.325
Term of warrants (in years)				5 years
Share price per common stock if warrants are exchanged in cash				$ 0.999
Warrant liabilities, at fair value				$ 1,900,000
Number of shares issued as a result of warrants exchanged in cash	7,777,778	2,222,222									10,000,000
Warrants outstanding				0						0	0
Change in fair value of warrant liability				$ 100,000
March 2023 Pre-Funded Warrants
Common Stock Offerings
Shares issuable upon exercise of warrants									26,750,000
March 2023 Pre-Funded Warrants | 2023 Securities Purchase Agreement
Common Stock Offerings
Exercise price of warrants										$ 9,300,000	$ 9,300,000		$ 0.001
Number of shares issued as a result of warrants exchanged in cash					6,611,820	2,719,999					9,300,000
Warrants outstanding									0
Shares issuable upon exercise of warrants								9,340,702	9,340,702
Registered direct offering | 2023 Securities Purchase Agreement | One share and one accompanying Common Warrant
Common Stock Offerings
Shares issuable upon exercise of combined warrants													1.25
Combined purchase price per share													$ 0.525
Registered direct offering | 2023 Securities Purchase Agreement | One pre-funded warrant and one accompanying common warrant
Common Stock Offerings
Shares issuable upon exercise of combined warrants													1.25
Combined purchase price per share													$ 0.524

License Agreements (Details)

License Agreements (Details)												1 Months Ended		3 Months Ended		9 Months Ended
	Feb. 28, 2023 USD ($)	Jan. 31, 2023 USD ($)	Jan. 11, 2023 USD ($)	Jan. 03, 2023 USD ($)	Jul. 11, 2022 shares	Apr. 11, 2022 shares	Apr. 08, 2022 USD ($)	Jan. 02, 2022 USD ($)	Jan. 02, 2021 USD ($)	Jan. 02, 2020 USD ($)	Aug. 29, 2019 USD ($)	Jul. 31, 2022 USD ($)	Apr. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 22, 2022 USD ($)
License Agreements
Issuance of common stock, net of issuance costs			$ 1,000,000
Research and development														$ 10,022,000	$ 14,750,000	$ 24,199,000	$ 43,115,000
Other														43,000		43,000		$ 89,000
Non refundable cash payment																1,200,000
Research and development expense - Vyera repurchase																500,000
Assets from Vyera Pharmaceuticals
License Agreements
Percentage of upfront payment							4%
Cash payments agreed to in amendment to the asset purchase agreement							$ 4,000,000
Number of shares issued and sold | shares					500,000	500,000
Issuance of common stock, net of issuance costs												$ 800,000
Aggregate purchase price																			$ 1,200,000
Cash payment				$ 1,200,000									$ 4,000,000			4,000,000
Research and development																	$ 5,800,000
Other		$ 1,000,000
Number of cash payments made	500,000	500,000
Amount per each cash payment	$ 500,000	$ 500,000
Weg License Agreement
License Agreements
Upfront license fee											$ 75,000
Additional consideration agreed to pay								$ 200,000	$ 125,000	$ 100,000
Additional consideration paid								$ 200,000	$ 125,000	$ 100,000
Milestone payments accrued														$ 0		$ 0

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Accrued Expenses
Professional fees	$ 195	$ 278
Personnel related	1,121	1,288
Outside research and development services	4,909	5,627
Insurance	72
Other	43	89
Accrued expenses, net	$ 6,340	$ 7,282

Debt (Details)

Debt (Details) - USD ($)								3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 21, 2023	May 19, 2023	Nov. 23, 2022	Aug. 23, 2022	Dec. 02, 2021	Nov. 23, 2021	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	May 18, 2023
Debt
Percentage of debt converted in case of exercising prepayment right					33.33%
Convertible note liability	$ 16,900,000							$ 16,900,000		$ 16,900,000		$ 20,100,000
Loss on extinguishment of debt								(3,631,000)		(9,151,000)
Fair value of restricted common stock issued								962,000		3,929,000
Gain (loss) on change in fair value of convertible notes								(799,000)	$ (2,137,000)	(1,349,000)	$ (2,477,000)
Principal repayment										8,500,000
Principal repayment in common stock										3,500,000
Principal repayment in cash										5,000,000
Interest payments										600,000
Interest payment in common stock										300,000
Interest payment in cash										300,000		1,900,000
Lind securities purchase agreement | Lind
Debt
Amount receivable in private placement transaction							$ 20,000,000
Number of shares issued and sold							534,759
Convertible Promissory Note
Debt
Loss on extinguishment of debt								$ 3,600,000		$ 9,100,000
Convertible Promissory Note | 2021 Note
Debt
Conversion price	$ 6							$ 6		$ 6
Convertible note liability	$ 16,800,000							$ 16,800,000		$ 16,800,000
Percentage of minimum balance of outstanding principal balance to be maintained with one or more financial institutions										50%
Percentage of average of five lowest daily vwap during 20 trading days										85%
Number of days considered to calculate volume weighted average price										5 days
Threshold trading days for calculating volume weighted average price										20 days
Percentage of outstanding principal amount										120%
Convertible Promissory Note | Lind
Debt
Interest rate (in percent)	12%							12%		12%
Conversion price		$ 6
Number of shares issued to satisfy interest and principal payments	1,877,084
Convertible note liability	$ 16,837,084							$ 16,837,084		$ 16,837,084
Percentage of minimum balance of outstanding principal balance to be maintained with one or more financial institutions	50%
Percentage of average of five lowest daily vwap during 20 trading days		85%
Number of days considered to calculate volume weighted average price		5 days
Threshold trading days for calculating volume weighted average price		20 days
Amount to be paid		$ 686,564
Threshold period for conversion of monthly payment		45 days
Increase in outstanding principal amount	$ 3,631,528
Percentage of net cash proceeds to repay debt	25%
Amount of securities to be offered to lender	$ 5,000,000
Number of shares issuable pursuant to conversion	1,877,084
Convertible Promissory Note | Lind | Maximum
Debt
Aggregate amount for conversion into common stock		$ 400,000
Percentage of securities to be offered for participation in any equity or debt financing to lender	50%
Convertible Promissory Note | Lind securities purchase agreement | Lind
Debt
Amount receivable in private placement transaction						$ 201,534
Aggregate principal amount						$ 221,688	$ 22,000,000
Interest rate (in percent)				5%			5%
Number of shares issued and sold						5,388
Conversion price					$ 6
Amortization period				24 months
Percentage of five day VWAP of common stock				90%
Period of VWAP of common stock				5 days
Threshold trading days				20 days
Number of shares issued to satisfy interest and principal payments										5,468,461
2021 Note Amendment | Lind
Debt
Conversion price			$ 6
Convertible note liability			$ 17,750,000											$ 1,250,000
Loss on extinguishment of debt			$ 1,300,000
Percentage of minimum balance of outstanding principal balance to be maintained with one or more financial institutions			50%
Minimum monthly principal payments to be paid in cash			$ 600,000
Aggregate shares of common stock upon conversion of convertible notes			1,000,000
Fair value of restricted common stock issued			$ 1,000,000
2021 Note Amendment | Lind | For conversion price
Debt
Percentage of average of five lowest daily vwap during 20 trading days			85%
Number of days considered to calculate volume weighted average price			5 days
Threshold trading days for calculating volume weighted average price			20 days
2021 Note Amendment | Lind | For issue price per share on shares issuable
Debt
Percentage of average of five lowest daily vwap during 20 trading days			90%
Number of days considered to calculate volume weighted average price			5 days
Threshold trading days for calculating volume weighted average price			20 days
December 2021 separate securities purchase agreements
Debt
Loss on extinguishment of debt										$ 13,000
Gross proceeds from convertible debt													$ 20,200,000
Convertible subordinated debt						$ 19,200,000						20,000,000	18,900,000
Gain (loss) on change in fair value of convertible notes								$ 800,000	$ 100,000	$ 1,300,000	$ 300,000	$ 3,000,000	$ 200,000

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands												1 Months Ended	9 Months Ended
	Sep. 27, 2023	Sep. 26, 2023	Sep. 25, 2023	Sep. 21, 2023	Sep. 19, 2023	Jul. 03, 2023	Mar. 14, 2023	Mar. 10, 2023	Sep. 04, 2020	Aug. 23, 2019	Jan. 24, 2019	Sep. 30, 2020	Sep. 30, 2023	Sep. 30, 2022	May 19, 2023	Mar. 31, 2023	Dec. 31, 2022	Aug. 31, 2019
Stockholders' Equity
Preferred stock, authorized (in shares)													10,000,000				10,000,000
Preferred stock, par value (in USD per share)													$ 0.001				$ 0.001
Preferred stock, outstanding (in shares)													0				0
Common stock, authorized (in shares)													480,000,000				240,000,000
Exercise price of warrants											$ 4.15
Number of warrants to purchase common stock								9,340,702			1,463,519
Number of shares called by warrants issued								9,340,702			1,463,519
2023 Securities Purchase Agreement
Stockholders' Equity
Number of shares issued and sold							12,059,298	12,059,298					75,768
Aggregate net proceeds							$ 10,400	$ 10,400
September 2023 Securities Purchase Agreement
Stockholders' Equity
Number of shares issued and sold			15,000,000	15,000,000
Aggregate net proceeds				$ 4,100
September 2020 warrants
Stockholders' Equity
Warrants exercisable													1,000,000
August 232019
Stockholders' Equity
Number of shares issued and sold										4,475,000
September 2020 warrants
Stockholders' Equity
Exercise price of warrants												$ 0.84	$ 0.84
Number of shares issued and sold									8,865,000			6,648,750	6,648,750
Number of warrants exercised													0	0
August 2019 warrants
Stockholders' Equity
Exercise price of warrants													$ 1.78					$ 1.78
Number of shares issued and sold										2,237,500
Proceeds from warrant exercises													$ 0	$ 0
Warrants exercisable													900,000					2,237,500
May 2023 warrants | 2023 Securities Purchase Agreement
Stockholders' Equity
Shares issuable upon exercise of warrants															4,000,000
Exercise price of warrants													$ 1.06		$ 1.06
Warrants outstanding													4,000,000
Series A Warrants
Stockholders' Equity
Exercise price of warrants											$ 0.2734		$ 0.2734
Number of warrants to purchase common stock											3,629,023
Proceeds from warrant exercises													$ 0	$ 0
Warrants exercisable													300,000
Number of warrants issued											1,463,519
Number of shares called by warrants issued											3,629,023
Series A Warrants | Minimum
Stockholders' Equity
Exercise price of warrants													$ 0.2957
Series A Warrants | Maximum
Stockholders' Equity
Exercise price of warrants													0.2734
March 2023 Pre-Funded Warrants
Stockholders' Equity
Shares issuable upon exercise of warrants								26,750,000
March 2023 Pre-Funded Warrants | 2023 Securities Purchase Agreement
Stockholders' Equity
Shares issuable upon exercise of warrants							9,340,702	9,340,702
Exercise price of warrants													$ 9,300,000			$ 0.001
Number of shares issued as a result of warrants exchanged in cash					6,611,820	2,719,999							9,300,000
Warrants outstanding								0
Common warrants | 2023 Securities Purchase Agreement
Stockholders' Equity
Shares issuable upon exercise of warrants							26,750,000	26,750,000
Exercise price of warrants								$ 0.60					$ 0.60			$ 0.60
Warrants outstanding													26,800,000
September 2023 Warrants
Stockholders' Equity
Number of shares issued and sold				15,000,000
September 2023 Warrants | September 2023 Securities Purchase Agreement
Stockholders' Equity
Exercise price of warrants				$ 0.325
Share price per common stock if warrants are exchanged in cash				$ 0.999
Number of shares issued as a result of warrants exchanged in cash	7,777,778	2,222,222											10,000,000
Warrants outstanding				0									0
Number of warrants to purchase common stock			10,010,010	10,010,010
Number of shares called by warrants issued			10,010,010	10,010,010

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Warrant Activity (Details) - $ / shares shares in Thousands		9 Months Ended	12 Months Ended
	Jan. 24, 2019	Sep. 30, 2023	Dec. 31, 2022
Stockholders' Equity
Outstanding as of September 30, 2023, weighted-average exercise price (in usd per share)	$ 4.15
Warrant Derivative Financial Instruments
Stockholders' Equity
Outstanding as of December 31, 2022		2,545
Issued		50,101
Exercised		(19,351)
Cancelled		(1,021)
Outstanding as of September, 2023		32,274	2,545
Warrants exercisable as of September 30, 2023		32,274
Outstanding as of December 31, 2022, weighted-average exercise price (in usd per share)		$ 2.78
Issued, weighted-average exercise price		0.41
Exercised, weighted-average exercise price		0
Cancelled, weighted-average exercise price		3.38
Outstanding as of September 30, 2023, weighted-average exercise price (in usd per share)		0.74	$ 2.78
Exercisable, weighted-average exercise price (in usd per share)		$ 0.74
Weighted-average remaining contractual life (in years)		4 years 9 months 18 days	1 year 8 months 12 days
Exercisable as of September 30, 2023, weighted-average remaining contractual life (in years)		4 years 9 months 18 days

Stock-based Compensation - Sche

Stock-based Compensation - Schedule of Valuation Assumptions for Stock Options (Details) - Stock options - $ / shares	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Stock-based Compensation
Weighted-average fair value	$ 0.60	$ 1.22
Minimum
Stock-based Compensation
Risk-free interest rate, minimum	3.50%	1.60%
Volatility, minimum	116%	111%
Expected term (years)	5 years	5 years
Maximum
Stock-based Compensation
Risk-free interest rate, maximum	3.90%	3.40%
Volatility, maximum	119%	113%
Expected term (years)	6 years	6 years

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Stock Option Activity (Details) - $ / shares	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Stock-based Compensation
Granted	338,135
Exercised	0	(6,250)
Granted in period (USD per share)	$ 0.69
Outstanding stock options
Stock-based Compensation
Outstanding, beginning of period (share)	10,400,000
Granted	5,015,000
Forfeited	(47,000)
Expired	(26,000)
Outstanding, end of period (shares)	15,342,000
Vested and expected to vest, end of period (shares)	15,342,000
Exercisable, end of period (shares)	7,495,000
Outstanding, beginning of period (USD per share)	$ 2.26
Granted in period (USD per share)	0.70
Forfeited (USD per share)	1.91
Expired (USD per share)	87.60
Outstanding, end of period (USD per share)	1.60
Vested and expected to vest stock, end of period (USD per share)	1.60
Exercisable, end of period (USD per share)	$ 1.97
Outstanding - weighted-average remaining contractual life (in years)	8 years
Weighted-average remaining contractual life (in years) of vested and expected to vest stock options	8 years
Weighted-average remaining contractual life (in years) of exercisable stock options	7 years 2 months 12 days
Non qualified stock options to employees
Stock-based Compensation
Granted	2,959,625

Stock-based Compensation - Sc_2

Stock-based Compensation - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Stock-based Compensation
Stock-based compensation expense	$ 974	$ 973	$ 3,024	$ 4,166
Research and development
Stock-based Compensation
Stock-based compensation expense	267	261	770	721
General and administrative
Stock-based Compensation
Stock-based compensation expense	$ 707	$ 712	$ 2,254	$ 3,445

Stock-based Compensation - Addi

Stock-based Compensation - Additional information (Details) - USD ($)			3 Months Ended			9 Months Ended		12 Months Ended
	Jan. 01, 2023	May 15, 2020	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2021
Stock-based Compensation
Term of option grant						10 years
Stock-based compensation expense			$ 974,000	$ 973,000		$ 3,024,000	$ 4,166,000
Options granted in period						338,135
Weighted-average exercise price per share granted in period						$ 0.69
Stock option exercised						0	6,250
Stock options forfeited						73,000	0
Unrecognized stock option compensation expense			$ 7,500,000			$ 7,500,000
Weighted average period for recognition						2 years 25 days
2012 Plan
Stock-based Compensation
Number of shares added each year as a percentage of the number of shares of common stock issued and outstanding						4%
Common stock are available for future issuance			5,200,000			5,200,000
2012 Plan | Minimum
Stock-based Compensation
Vesting period						1 year
2012 Plan | Maximum
Stock-based Compensation
Vesting period						4 years
Term of option grant						10 years
ESPP
Stock-based Compensation
Number of additional shares authorized	1,063,421
Purchase price of common stock (in percent)						15%
Number of shares sold						149,122
Share based compensation						$ 27,000
Stock options
Stock-based Compensation
Number of additional shares authorized	4,771,457
Number of shares authorized			20,589,275			20,589,275
Purchase price of common stock (in percent)		85%
Options granted in period						5,015,000
Weighted-average exercise price per share granted in period						$ 0.70
ESPP
Stock-based Compensation
Number of shares authorized		1,000,000
2019 Inducement Plan
Stock-based Compensation
Number of shares authorized			1,000,000			1,000,000
Incentive stock option
Stock-based Compensation
Term of option grant						10 years
Options granted in period						1,517,585
Weighted-average exercise price per share granted in period						$ 0.69
Vesting percentage on the first anniversary						25%
Non qualified stock options to employees
Stock-based Compensation
Options granted in period						2,959,625
Non qualified stock options to non employee directors
Stock-based Compensation
Vesting period						12 months
Term of option grant						10 years
Options granted in period						200,000
Weighted-average exercise price per share granted in period						$ 0.81
Performance stock award | Performance stock unit award to Executive
Stock-based Compensation
Stock-based compensation expense					$ 4,900,000	$ 1,300,000
Fair value of common stock								2,400,000
Weighted-average fair value (in USD per share)								$ 4.31
Compensation cost			$ 0			$ 0

Commitments and Contingencies_2

Commitments and Contingencies (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Oct. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Mar. 31, 2021
Commitments and Contingencies
Operating lease right-of-use asset		$ 30		$ 72
weighted-average remaining lease term		6 months
Weighted-average discount rate		8%
Rent expense		$ 47,000	$ 42,000
March 2021 Lease
Commitments and Contingencies
Lease term					18 months
October 2022 Lease
Commitments and Contingencies
Lease term	18 months
Lease base rent per month	$ 4,500
Operating lease right-of-use asset	$ 86,000

Commitments and Contingencies -

Commitments and Contingencies - Future Minimum Lease Payments (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Future minimum lease payments for the Company's operating lease with a non-cancelable term
Year Ended December 31, 2023	$ 16
Year Ended December 31, 2024	16
Total	32
Less present value discount	(2)
Operating lease liabilities	$ 30