Seelos Therapeutics (SEELQ) 10-Q 6 Aug 21 2021 Q2 Quarterly report Financial data

Cover

Cover - shares	6 Months Ended
	Jun. 30, 2021	Jul. 29, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2021
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2021
Current Fiscal Year End Date	--12-31
Entity File Number	000-22245
Entity Registrant Name	SEELOS THERAPEUTICS, INC.
Entity Central Index Key	0001017491
Entity Tax Identification Number	87-0449967
Entity Incorporation, State or Country Code	NV
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		102,315,208

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets
Cash	$ 87,200	$ 15,662
Prepaid expenses and other current assets	3,046	1,832
Total current assets	90,246	17,494
Operating lease right-of-use asset	63
Total assets	90,309	17,494
Current liabilities
Accounts payable	1,038	1,887
Accrued expenses	2,569	1,924
Licenses payable	3,200	125
Convertible debt	4	2,431
Warrant liabilities, at fair value	733	1,062
Operating lease liability	51
Total current liabilities	7,595	7,429
Licenses payable, long-term		200
Operating lease liability, long-term	12
Note payable		147
Convertible debt, long-term	4	7,146
Total liabilities	7,611	14,922
Commitments and contingencies (note 10)
Stockholders’ equity
Common stock, $0.001 par value, 240,000,000 and 120,000,000 shares authorized,          102,271,544 and 54,535,891 issued and outstanding as of          June 30, 2021 and December 31, 2020, respectively	102	54
Additional paid-in-capital	185,732	77,680
Accumulated deficit	(103,136)	(75,162)
Total stockholders’ equity	82,698	2,572
Total liabilities and stockholders’ equity	$ 90,309	$ 17,494

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, per 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)	240,000,000	120,000,000
Common stock, issued (in shares)	102,271,544	54,535,891
Common stock, outstanding (in shares)	102,271,544	54,535,891

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Operating expense
Research and development	$ 4,308	$ 1,444	$ 18,420	$ 5,137
General and administrative	2,465	1,876	4,965	3,692
Total operating expense	6,773	3,320	23,385	8,829
Loss from operations	(6,773)	(3,320)	(23,385)	(8,829)
Other income (expense)
Interest income	29	7	48	34
Interest expense	(583)	(3)	(1,573)	(7)
Net loss on extinguishment of debt	(2,387)		(2,387)
Gain on forgiveness of debt	149		149
Change in fair value of warrant liabilities	707	(413)	(826)	241
Total other income (expense)	(2,085)	(409)	(4,589)	268
Net loss and comprehensive loss	$ (8,858)	$ (3,729)	$ (27,974)	$ (8,561)
Net loss per share basic and diluted	$ (0.10)	$ (0.08)	$ (0.36)	$ (0.22)
Weighted-average common shares outstanding     basic and diluted	87,995,447	44,157,059	78,576,716	39,136,126

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Changes in Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Beginning balance, value at Dec. 31, 2019	$ 27	$ 56,027	$ (56,061)	$ (7)
Common Stock, Shares, Outstanding, Beginning Balance at Dec. 31, 2019	27,028,533
Stock-based compensation expense		652		652
[custom:IssuanceOfCommonStockForPrepaidServices]		330		330
Issuance of common stock for license acquired	$ 2	2,441		2,443
Issuance of common stock for license acquired, shares	1,809,845
Issuance of common stock, net of issuance costs	$ 15	8,835		8,850
Net Income (Loss) Attributable to Parent			(8,561)	(8,561)
Issuance of common stock, net of issuance costs, shares	15,166,666
Net loss			(8,561)	(8,561)
Ending balance, value at Jun. 30, 2020	$ 44	68,285	(64,622)	3,707
Common Stock, Shares, Outstanding, Ending Balance at Jun. 30, 2020	44,405,044
Issuance of common stock for prepaid services		330		330
Issuance of common stock for prepaid services, shares	400,000
Beginning balance, value at Mar. 31, 2020	$ 44	67,614	(60,893)	6,765
Common Stock, Shares, Outstanding, Beginning Balance at Mar. 31, 2020	44,005,044
Stock-based compensation expense		341		341
[custom:IssuanceOfCommonStockForPrepaidServices]		330		330
Net Income (Loss) Attributable to Parent			(3,729)	(3,729)
Net loss			(3,729)	(3,729)
Ending balance, value at Jun. 30, 2020	$ 44	68,285	(64,622)	3,707
Common Stock, Shares, Outstanding, Ending Balance at Jun. 30, 2020	44,405,044
Issuance of common stock for prepaid services		330		330
Issuance of common stock for prepaid services, shares	400,000
Beginning balance, value at Dec. 31, 2020	$ 54	77,680	(75,162)	$ 2,572
Common Stock, Shares, Outstanding, Beginning Balance at Dec. 31, 2020	54,535,891			54,535,891
Stock-based compensation expense		1,742		$ 1,742
Issuance of common stock, ESPP, shares	40,518			40,518
Stock Issued During Period, Value, Conversion of Convertible Securities, Net of Adjustments	$ 7	8,401		$ 8,408
Issuance of common stock, ESPP		30		30
Warrants exercised for cash, shares	7,431,125
Issuance of common stock for conversion of debt, shares	25,401
Issuance of common stock for extinguishment of debt, shares	406,250
Issuance of common stock, options exercised		65		65
Issuance of common stock for conversion of debt		40		40
Issuance of common stock, options exercised, shares	43,805
Extinguishment of beneficial conversion feature		(1,519)		(1,519)
Issuance of common stock for settlement of debt	1	1,376		1,377
Stock Issued During Period, Value, Employee Stock Ownership Plan		30		30
Warrants exercised for cash	7	8,401		8,408
Issuance of common stock, net of issuance costs	40	97,917		97,957
Net Income (Loss) Attributable to Parent			(27,974)	(27,974)
Issuance of common stock, net of issuance costs, shares	39,788,554
Net loss			(27,974)	(27,974)
Ending balance, value at Jun. 30, 2021	$ 102	185,732	(103,136)	$ 82,698
Common Stock, Shares, Outstanding, Ending Balance at Jun. 30, 2021	102,271,544			102,271,544
Beginning balance, value at Mar. 31, 2021	$ 78	118,960	(94,278)	$ 24,760
Common Stock, Shares, Outstanding, Beginning Balance at Mar. 31, 2021	78,283,021
Stock-based compensation expense		1,037		1,037
Stock Issued During Period, Value, Conversion of Convertible Securities, Net of Adjustments	$ 1	1,384		1,385
Warrants exercised for cash, shares	1,285,000
Issuance of common stock for conversion of debt, shares	25,401
Issuance of common stock for extinguishment of debt, shares	406,250
Issuance of common stock, options exercised
Issuance of common stock for conversion of debt		40		40
Issuance of common stock, options exercised, shares	13,806
Extinguishment of beneficial conversion feature		(1,519)		(1,519)
Issuance of common stock for settlement of debt	1	1,376		1,377
Warrants exercised for cash	1	1,384		1,385
Issuance of common stock, net of issuance costs	22	64,454		64,476
Net Income (Loss) Attributable to Parent			(8,858)	(8,858)
Issuance of common stock, net of issuance costs, shares	22,258,066
Net loss			(8,858)	(8,858)
Ending balance, value at Jun. 30, 2021	$ 102	$ 185,732	$ (103,136)	$ 82,698
Common Stock, Shares, Outstanding, Ending Balance at Jun. 30, 2021	102,271,544			102,271,544

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities
Net loss	$ (27,974)	$ (8,561)
Adjustments to reconcile net loss to net cash used in operating activities
Stock-based compensation expense	1,742	652
Shares issued for services		124
Research and development expenses - license acquired		192
Change in fair value of warrant liability	826	(241)
Gain on forgiveness of note payable	(147)
Net loss on extinguishment of convertible debt	2,387
Amortization of debt discount	1,564
Changes in operating assets and liabilities
Prepaid expenses and other current assets	(1,214)	(864)
Accounts payable	(849)	(166)
Accrued expenses	644	(690)
Licenses payable	2,875	(3,850)
Net cash used in operating activities	(20,146)	(13,404)
Cash flows provided by financing activities
Payment of convertible note	(13,620)
Proceeds from issuance of common stock, net of issuance costs	97,957
Proceeds from issuance of common stock and warrants, pursuant to          Securities Purchase Agreement, net of issuance costs		8,850
Proceeds from exercise of warrants	7,252
Proceeds from exercise of options	65
Proceeds from sales of common stock under ESPP	30
Proceeds from note payable		147
Net cash provided by financing activities	91,684	8,997
Net increase (decrease) in cash	71,538	(4,407)
Cash, beginning of period	15,662	10,261
Cash, end of period	87,200	5,854
Supplemental disclosure of cash flow information:
Cash paid for interest	8	8
Cash paid for income taxes
Non-cash investing and financing activities:
Reclass of warrant liabilities related to Series A warrants exercised for cash	1,155
Right-of-use assets obtained in exchange for operating lease liabilities	75
Issuance of common stock for convertible notes	40
Issuance of common stock for settlement of debt	1,377
Extinguishment of beneficial conversion feature	1,519
Issuance of common stock for license payable		$ 2,443

1. Organization and Description

1. Organization and Description of Business	6 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
1. Organization and Description of Business	1. Organization and Description of Business Seelos Therapeutics, Inc. and 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”). SLS-005 for the potential treatment of Sanfilippo syndrome currently requires additional natural history data, which is being explored. Additionally, the Company is developing several preclinical programs, most of which have well-defined mechanisms of action, including: SLS-004, SLS-006, SLS-007 for the potential treatment of Parkinson’s Disease (“PD”) and SLS-008, which is being developed for the potential treatment of an undisclosed indication, but may also be targeted at chronic inflammation in asthma and orphan indications such as pediatric esophagitis.

2. Liquidity

2. Liquidity	6 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
2. Liquidity	2. Liquidity 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 June 30, 2021, the Company had $87.2 million in cash and an accumulated deficit of $103.1 million. The Company has historically funded its operations through the issuance of convertible notes (see Note 6), the sale of common stock (see Note 4) and exercises of warrants (see Note 7). On May 24, 2021, the Company completed an underwritten public offering, pursuant to which the Company sold 22,258,066 3.10 64.5 7.3 On January 28, 2021, the Company completed an underwritten public offering, pursuant to which the Company sold 17,530,488 2.05 33.5 3.8 The Company currently has an effective shelf registration statement on Form S-3 filed with the Securities and Exchange Commission (the “SEC”). The Company may use the shelf registration statement on Form S-3 to offer from time to time any combination of debt securities, common and preferred stock and warrants. As of June 30, 2021, the Company had approximately $ 95.1 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, which are subject to change, management believes that the Company’s existing cash and cash equivalents as of June 30, 2021 are sufficient to satisfy its operating cash needs 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; • its ability to secure a development partner for its product candidate in the United States for the treatment of erectile dysfunction (the “CVR Product Candidate”) in order to overcome deficiencies raised in the 2018 complete response letter issued by the U.S. Food and Drug Administration (the “FDA”) related to the CVR Product Candidate; and • its ability to increase the number of authorized shares outstanding to facilitate future financing events. The Company may determine to raise additional funds 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. As noted above, management believes that the Company’s existing cash and cash equivalents as of June 30, 2021 are sufficient to satisfy its operating cash needs for the year after the filing of this Quarterly Report on Form 10-Q. However, 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. 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. Debt financing may involve agreements that include covenants limiting or restricting the Company’s ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends, and may be secured by all or a portion of the Company’s assets.

3. Significant Accounting Polic

3. Significant Accounting Policies	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
3. 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, 2020 included in the Company’s Annual Report on Form 10-K (“Annual Report”) filed with the SEC on March 11, 2021. 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, 2020 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 common stock 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. 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 (in thousands): Schedule of Fair Value Hierarchy Assets and Liabilities Fair Value Measurements as of June 30, 2021 (Level 1) (Level 2) (Level 3) Total Assets Cash $ 87,200 $ - $ - $ 87,200 Liabilities Warrant liabilities, at fair value $ - $ - $ 733 $ 733 Fair Value Measurements as of December 31, 2020 (Level 1) (Level 2) (Level 3) Total Assets Cash $ 15,662 $ - $ - $ 15,662 Liabilities Warrant liabilities, at fair value $ - $ - $ 1,062 $ 1,062 There were no transfers between fair value measurement levels during the six months ended June 30, 2021. The Company’s warrant liabilities The common stock warrant liabilities were 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 June 30, 2021: Summary of Fair Value Measurements Valuation Assumptions Six Months Ended June 30, 2021 Risk-free interest rate 0.37% Volatility 119.55% Dividend yield - Expected term (in years) 2.57 Weighted-average fair value $ 2.43 The following table is a reconciliation for the common stock warrant liabilities measured at fair value using Level 3 unobservable inputs (in thousands): Schedule of Fair Value Level 3 Reconciliation Warrant liabilities Balance as of December 31, 2020 $ 1,062 Warrant liability reclassified to stockholders' equity (1,155) Change in fair value measurement of warrant liability 826 Balance as of June 30, 2021 $ 733 Stock-based Compensation The Company expenses stock-based compensation to employees, non-employees and board members over the requisite service period for the entire award, except for performance condition awards where vesting is subject to the Company achieving certain performance criteria, based on the estimated grant-date fair value of the awards and forfeitures rates. Compensation costs for performance condition awards will be recognized when the achievement of the performance criteria is probable. 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. Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in operating lease right-of-use (“ROU”) asset, operating lease liability, current and operating lease liability, long-term in the Company’s condensed consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liability represents its obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the commencement date based on the present value of the lease payments over the lease term. As the Company’s leases do not provide an implicit rate, the Company uses an incremental borrowing rate based on the information available at the transition date and commencement date in determining the present value of lease payments. This is the rate the Company would have to pay if it borrowed on a collateralized basis over a similar term to each lease. The operating lease ROU asset also includes any lease payments made and excludes lease incentives. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term. Net Loss Per Share Basic loss per share is computed by dividing net 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. In computing the basic and diluted net loss per share applicable to common stockholders, the weighted average number of shares remains the same for both calculations due to the fact that when a net loss exists, dilutive shares are not included in the calculation as the impact is anti-dilutive. The following potentially dilutive securities outstanding for the three and six months ended June 30, 2021 and 2020 have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive (in thousands): Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Three and Six Months Ended June 30, 2021 2020 Outstanding stock options 7,199 4,925 Restricted stock units 2,400 67 Outstanding warrants 2,635 3,584 Convertible debt 17 - 12,251 8,576 Amounts in the table reflect the common stock equivalents of the noted instruments. Recent Accounting Pronouncements In December 2019, the FASB issued Accounting Standards Update The Company adopted ASU 2019-12 effective January 1, 2021. The adoption of ASU 2019-12 did not have a material effect on the Company’s financial statements. In August 2020, the FASB issued ASU 2020-06: Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity. 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 fiscal years beginning after December 15, 2021, 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 is evaluating the impact of ASU 2020-06 on its consolidated financial statements and related disclosures.

4. Common Stock Offerings

4. Common Stock Offerings	6 Months Ended
	Jun. 30, 2021
Business Combination and Asset Acquisition [Abstract]
4. Common Stock Offerings	4. Common Stock Offerings Securities Purchase Agreements December 2020 Convertible Note and Private Placement In December 2020, the Company sold 1,112,219 10.9 2020 Registered Direct Offering and Concurrent Private Placement On September 4, 2020, the Company entered into a Securities Purchase Agreement with certain institutional investors (the “2020 Securities Purchase Agreement”) pursuant to which the Company issued and sold an aggregate of 8,865,000 6.4 The Company also issued to the investors 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 have an exercise price of $0.84 per share of common stock, became exercisable beginning on March 9, 2021 and will expire on March 9, 2026. The combined purchase price for one share and one warrant to purchase 0.75 of a share of common stock in the offerings was $ 0.79 Consulting Agreement On May 11, 2020, the Company entered into a consulting agreement (the “Consulting Agreement”) with an advisory firm, pursuant to which the advisory firm agreed to provide the Company with certain management consulting, business and advisory services. The Company agreed to issue the advisory firm 300,000 On June 9, 2020, the Company and the advisory firm entered into an amendment to the Consulting Agreement (the “Amendment”). Pursuant to the Amendment, the advisory firm agreed to provide the Company with additional services and, in consideration, the Company agreed to issue the advisory firm an additional 200,000 unregistered shares of the Company’s common stock (the “Additional Shares”), plus $20,000 in cash. The Additional Shares were issued to the advisory firm on June 9, 2020 and were subject to certain vesting restrictions. Through September 30, 2020, the Company has recognized approximately $ 431,000 Public Offerings On May 24, 2021, the Company completed an underwritten public offering, pursuant to which the Company sold 22,258,066 3.10 64.5 7.3 On January 28, 2021, the Company completed an underwritten public offering, pursuant to which the Company sold 17,530,488 2.05 33.5 3.8 On March 16, 2020, the Company completed an underwritten public offering pursuant to which it sold 7,500,000 0.60 4.0 On February 13, 2020, the Company completed an underwritten public offering, pursuant to which it sold 6,666,667 0.75 999,999 0.75 4.8 Stock Purchase Agreement with Vyera On January 2, 2020, the Company entered into a stock purchase agreement (the “Stock Purchase Agreement”) with Vyera, pursuant to which the Company issued to Vyera 1,809,845 Pre-Merger Financing On January 24, 2019, Apricus Biosciences, Inc., a Nevada corporation (“Apricus”), completed a business combination with Seelos Therapeutics, Inc., a Delaware corporation (“STI”), in accordance with the terms of the Agreement and Plan of Merger and Reorganization (the “Merger Agreement”) entered into on July 30, 2018. Pursuant to the Merger Agreement, (i) a subsidiary of Apricus merged with and into STI, with STI (renamed as “Seelos Corporation”) continuing as a wholly owned subsidiary of Apricus and the surviving corporation of the merger and (ii) Apricus was renamed as “Seelos Therapeutics, Inc.” (the “Merger”). On January 24, 2019, STI and Apricus closed a private placement transaction with certain accredited investors (the “Investors”), whereby, among other things, STI issued to investors shares of STI’s common stock immediately prior to the Merger in a private placement transaction (the “Financing”), pursuant to a Securities Purchase Agreement, made and entered into as of October 16, 2018, by and among STI, Apricus and the investors, as amended (the “Purchase Agreement”). Pursuant to the Purchase Agreement, STI (i) issued and sold to the Investors an aggregate of 2,374,672 shares of STI’s common stock which converted pursuant to the exchange ratio in the Merger into the right to receive 1,829,407 shares of the Company’s common stock and (ii) issued warrants representing the right to acquire 1,463,519 shares of common stock at a price per share of $4.15, subject to adjustment as provided therein (the “Series A Warrants”), most recently adjusted to a price per share of $0.2957 per share, and additional warrants initially representing the right to acquire no shares of common stock at a price per share of $0.001, subject to adjustment as provided therein (the “Series B Warrants” together with the Series A Warrants, the “Investor Warrants”), for aggregate gross proceeds of $18.0 million, or $16.5 million net of financing fees. The terms of the Investor Warrants included certain provisions that could result in adjustments to both the number of warrants issued and the exercise price of each warrant, which resulted in the warrants being classified as a liability upon issuance (see Note 7). The Investor Warrants were recorded at fair value of $21.5 million upon issuance and given that the liability exceeded the proceeds received, a loss of $5.0 million was recognized. On March 7, 2019, the Company entered into Amendment Agreements (collectively, the “Amendment Agreements”) with each Investor amending: (i) the Purchase Agreement, (ii) the Series A Warrants, and (iii) the Series B Warrants. The Amendment Agreements, among other things, fixed the aggregate number of shares of common stock issued and issuable pursuant to the Series A Warrants at 3,629,023 (none of which were exercised as of March 7, 2019). The terms of the Investor Warrants continue to include certain provisions that could result in a future adjustment to the exercise price of the Investor Warrants and accordingly, they continue to be classified as a liability after the Amendment Agreements. At June 30, 2021, 0.3

5. License Agreements

5. License Agreements	6 Months Ended
	Jun. 30, 2021
Research and Development [Abstract]
5. License Agreements	5. License Agreements Acquisition of License from Ligand Pharmaceuticals Incorporated On September 21, 2016, the Company entered into a License Agreement (the “License Agreement”) with Ligand Pharmaceuticals Incorporated (“Ligand”), Neurogen Corporation and CyDex Pharmaceuticals, Inc. (collectively, the “Licensors”), pursuant to which, among other things, the Licensors granted to the Company an exclusive, perpetual, irrevocable, worldwide, royalty-bearing, nontransferable right and license under (i) patents related to a product known as Aplindore, which is now known as SLS-006, acetaminophen (as it may have been or may be modified for use in a product to be administered by any method in any form including, without limitation injection and intravenously, the sole active pharmaceutical ingredient of which is acetaminophen), which is now known as SLS-012, an H3 receptor antagonist, which is now known as SLS-010, and either or both of the Licensors’ two proprietary CRTh2 antagonists, which are now known collectively as SLS-008 (collectively, the “Licensed Products”), and (ii) copyrights, trade secrets, moral rights and all other intellectual and proprietary rights related thereto. The Company is obligated to use commercially reasonable efforts to (a) develop the Licensed Products, (b) obtain regulatory approval for the Licensed Products in the European Union (either in its entirety or including at least one of France, Germany or, if at the time the United Kingdom is a member of the European Union, the United Kingdom), the United Kingdom, if at the time the United Kingdom is not a member of the European Union, Japan or the People’s Republic of China (each, a “Major Market”) or the United States, and (c) commercialize the Licensed Products in each country where regulatory approval is obtained. The Company has the exclusive right and sole responsibility and decision-making authority to research and develop any Licensed Products and to conduct all clinical trials and non-clinical studies the Company believes appropriate to obtain regulatory approvals for commercialization of the Licensed Products. The Company also has the exclusive right and sole responsibility and decision-making authority to commercialize any of the Licensed Products. In connection with the closing of the Merger, the Company issued 801,253 2.2 The Company also agreed to pay to Ligand certain one-time, non-refundable regulatory milestone payments in connection with the Licensed Products, other than in connection with Aplindore for the indication of PD or Restless Leg Syndrome, consisting of (i) $750,000 upon submission of an application with the FDA or equivalent foreign body for a particular Licensed Product, (ii) $3.0 million upon FDA approval of an application for a particular Licensed Product, (iii) $1.125 million upon regulatory approval in a Major Market for a particular Licensed Product, and (iv) $1.125 million upon regulatory approval in a second Major Market for a particular Licensed Product. The Company also agreed to pay to Ligand certain one-time, non-refundable regulatory milestone payments in connection with the Licensed Products in connection with Aplindore for the indication of PD or Restless Leg Syndrome, consisting of (i) $100,000 upon submission of an application with the FDA or equivalent foreign body for such a particular Licensed Product, (ii) $350,000 upon FDA approval of an application for such a particular Licensed Product, (iii) $125,000 upon regulatory approval in a Major Market for such a particular Licensed Product, and (iv) $125,000 upon regulatory approval in a second Major Market for such a particular Licensed Product. The Company agreed to pay to Ligand certain one-time, non-refundable commercial milestone payments in connection with the Licensed Products, consisting of (i) $10.0 million upon the achievement of $1.0 billion of cumulative worldwide net sales of Licensed Products based upon Aplindore, (ii) $10.0 million upon the achievement of $1.0 billion of cumulative worldwide net sales of Licensed Products based upon an H3 receptor antagonist, (iii) $10.0 million upon the achievement of $1.0 billion of cumulative worldwide net sales of Licensed Products based upon acetaminophen (as it may have been or may be modified for use in a product to be administered by any method in any form including, without limitation injection and intravenously, the sole active pharmaceutical ingredient of which is acetaminophen), (iv) $10.0 million upon the achievement of $1.0 billion of cumulative worldwide net sales of Licensed Products based upon CRTh2 antagonists, (v) $20.0 million upon the achievement of $2.0 billion of cumulative worldwide net sales of Licensed Products based upon Aplindore, (vi) $20.0 million upon the achievement of $2.0 billion of cumulative worldwide net sales of Licensed Products based upon an H3 receptor antagonist, (vii) $20.0 million upon the achievement of $2.0 billion of cumulative worldwide net sales of Licensed Products based upon acetaminophen (as it may have been or may be modified for use in a product to be administered by any method in any form including, without limitation injection and intravenously, the sole active pharmaceutical ingredient of which is acetaminophen), and (viii) $20.0 million upon the achievement of $2.0 billion of cumulative worldwide net sales of Licensed Products based upon CRTh2 antagonists. The Company will also pay to Ligand middle single-digit royalties on aggregate annual net sales of Licensed Products other than in connection with Aplindore for the indication of PD or Restless Leg Syndrome in a country where such Licensed Products are covered under a licensed patent and a tiered incremental royalty in the upper single digit to lower double digit range on aggregate annual net sales of Licensed Products in connection with Aplindore for the indication of PD or Restless Leg Syndrome in a country where such Licensed Products are covered under a licensed patent. Additionally, the Company will pay to Ligand low single digit royalties on aggregate annual net sales of Licensed Products other than in connection with Aplindore for the indication of PD or Restless Leg Syndrome in a country where such Licensed Products are not covered under a licensed patent and a tiered incremental royalty in the lower single digit to middle single digit range on aggregate annual net sales of Licensed Products in connection with Aplindore for the indication of PD or Restless Leg Syndrome in a country where such Licensed Products are not covered under a licensed patent. The potential regulatory and commercial milestones are not yet considered probable, and no Acquisition of Assets from Vyera On March 6, 2018, the Company entered into the Vyera Agreement with Vyera, pursuant to which the Company acquired the assets (the “Vyera Assets”) and liabilities (the “Vyera Assumed Liabilities”), of Vyera related to TUR-002 (intranasal ketamine), which is now known as SLS-002. The Company is obligated to use commercially reasonable efforts to seek regulatory approval in the United States for and commercialize SLS-002 As consideration for the Vyera Assets, the Company paid to Vyera a non-refundable cash payment of $ 150,000 150,000 191,529 1,000,000 Pursuant to the amendment to the Asset Purchase Agreement entered into by the Company and Vyera on October 15, 2019, the Company issued Vyera 1,809,845 750,000 750,000 1.0 1.0 On February 15, 2021, the Company entered into an amendment to the Vyera Agreement. Pursuant to the amendment, the Company agreed to make cash payments to Vyera in the amount of $ 3.0 In the event that the Company sells, directly or indirectly, all or substantially all of the Vyera Assets to a third party, then the Company must pay Vyera an amount equal to 4% of the net proceeds actually received by the Company as an upfront payment in such sale. The Company agreed to pay to Vyera certain one-time, non-refundable milestone payments consisting of (i) $10.0 million upon approval by the FDA of a new drug application (an “NDA”), with respect to SLS-002, (ii) $5.0 million upon approval by the European Medicines Agency (the “EMA”) of the foreign equivalent to an NDA with respect to SLS-002 in a Major Market, (iii) $2.5 million upon approval by the EMA of the foreign equivalent to an NDA with respect to SLS-002 in a second Major Market, (iv) $5.0 million upon the achievement of $250.0 million in net sales of SLS-002, (v) $10.0 million upon the achievement of $500.0 million in net sales of SLS-002, (vi) $15.0 million upon the achievement of $1.0 billion in net sales of SLS-002, (vii) $20.0 million upon the achievement of $1.5 billion in net sales of SLS-002, and (vii) $25.0 million upon the achievement of $2.0 billion in net sales of SLS-002. The Company will also pay to Vyera a royalty percentage in the mid-single digits on aggregate annual net sales of SLS-002. The potential regulatory and commercial milestones are not yet considered probable, and no 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 an NDA for a product containing ketamine in any dosage on or before December 31, 2021, $ 0.2 0.1 0.125 The potential regulatory and commercial milestones are not yet considered probable, and no Acquisition of Assets from Bioblast Pharma Ltd. (“Bioblast”) On February 15, 2019, the Company entered into an Asset Purchase Agreement (the “Bioblast Asset Purchase Agreement”) with Bioblast. Pursuant to the Bioblast Asset Purchase Agreement, the Company acquired all of the assets of Bioblast relating to a therapeutic platform known as Trehalose (the “Bioblast Asset Purchase”). The Company paid to Bioblast $ 1.5 2.0 3.5 The potential regulatory and commercial milestones are not yet considered probable, and no Acquisition of License from The Regents of the University of California On March 7, 2019, the Company entered into an exclusive license agreement (the “UC Regents License Agreement”) with The Regents of the University of California (“The UC Regents”) pursuant to which the Company was granted an exclusive license to intellectual property owned by The UC Regents pertaining to a technology that was created by researchers at the University of California, Los Angeles (UCLA). Such technology relates to a family of rationally-designed peptide inhibitors that target the aggregation of alpha-synuclein (α-synuclein). The Company plans to study this initial approach in PD and will further evaluate the potential clinical approach in other disorders affecting the CNS. This program is now known as SLS-007. Upon entry into the UC Regents License Agreement, the Company paid to The UC Regents $ 0.1 0.1 The potential regulatory and commercial milestones are not yet considered probable, and no Acquisition of License from Duke University On June 27, 2019, the Company entered into an exclusive license agreement (the “Duke License Agreement”) with Duke University pursuant to which the Company was granted an exclusive license to a gene therapy program targeting the regulation of the synuclein alpha (“SNCA”) gene, which encodes alpha-synuclein expression. The Company plans to study this initial approach in PD and will further evaluate the potential clinical approach in other disorders affecting the CNS. This program is now known as SLS-004. Upon entry into the Duke License Agreement, the Company paid to Duke University $ 0.1 0.1 The potential regulatory and commercial milestones are not yet considered probable, and no

6. Debt

6. Debt	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
6. Debt	6. Debt December 2020 Convertible Note and Private Placement On December 11, 2020, the Company entered into a Securities Purchase Agreement (the “Lind Securities Purchase Agreement”) with Lind Global Asset Management II, LLC (“Lind”) pursuant to which, among other things, on December 11, 2020, the Company issued and sold to the Investor, in a private placement transaction, in exchange for the payment by Lind of $10,000,000, (1) a convertible promissory note (the “Note”) in an aggregate principal amount of $12,000,000 (the “Principal Amount”), which will bear no interest and mature on December 11, 2022 (the “Maturity Date”), and (2) 975,000 shares of the Company’s common stock. At any time following June 11, 2021, and from time to time before the Maturity Date, the Investor had the option to convert any portion of the then-outstanding Principal Amount of the Note into shares of common stock at a price per share of $1.60, subject to adjustment for stock splits, reverse stock splits, stock dividends and similar transactions (the “Conversion Price”). Prior to June 11, 2021, the Company had the right to prepay up to sixty-six and two-thirds percent (66 2/3%) of the then-outstanding Principal Amount of the Note with no penalty. Subject to certain exceptions, the Company was 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 Note, unless waived by the Investor in advance. The Note began amortizing in June 2021 and was to amortize in eighteen monthly installments equal to the quotient of (i) the then-outstanding Principal Amount of the Note, divided by (ii) the number of months remaining until the Maturity Date. All amortization payments were to be payable solely in cash, plus a 2% premium. On June 14, 2021, the Company and Lind entered into an Acknowledgment and Termination Agreement, pursuant to which the Company agreed to issue to Lind an aggregate of 406,250 additional shares of its common stock (the “Lind Shares”) and pay Lind the remaining principal amount of $790,804 (the “Final Payment”) in full satisfaction the Company’s remaining obligations to Lind under the Note. The Company issued the Lind Shares and made the Final Payment to Lind, and the Lind Securities Purchase Agreement and the Note terminated, effective June 15, 2021. The Company recorded a loss on extinguishment of debt of $1.4 million for the issuance of the 406,250 shares during the three and six months ended June 30, 2021. On December 17, 2020, the Company entered into three separate securities purchase agreements with certain accredited investors on substantially the same terms as the Lind Securities Purchase Agreement (the “December 17 SPAs”), pursuant to which the Company sold, in private placement transactions, in exchange for the payment by the accredited investors of an aggregate of $1,138,023, (1) convertible promissory notes (the “December 17 Notes”) in an aggregate principal amount of $1,365,628, which will bear no interest and mature on December 17, 2022, and (2) an aggregate of 110,956 shares of its common stock. On December 18, 2020, the Company entered into an additional securities purchase agreement with an accredited investor on substantially the same terms as the Lind Securities Purchase Agreement (the “December 18 SPA” and, together with the December 17 SPAs, the "Subsequent Securities Purchase Agreements"), pursuant to which the Company sold, in a private placement transaction, in exchange for the payment by the accredited investor of $269,373, (1) a convertible promissory note in an aggregate principal amount of $323,247, which will bear no interest and mature on December 18, 2022 (the “December 18 Note” and, together with the December 17 Notes, the “Subsequent Notes”), and (2) 26,263 shares of the Company’s common stock. The Subsequent Securities Purchase Agreements have substantially the same terms as the Lind Securities Purchase Agreement, and the Subsequent Notes have substantially the same terms as the Note. The Company received aggregate net proceeds of $10.9 million from the convertible note offerings, net of $0.5 million of issuance costs. The total gross proceeds were allocated to the convertible notes and common stock issued under the agreements based on their relative fair values. The Company recognized a beneficial conversion feature discount on the convertible notes of approximately $0.1 million. Due to the principal payments made during the year, the Company remeasured the beneficial conversion feature discount at each payment date and recorded a loss on extinguishment of debt of approximately $1.0 million during the three and six months ended June 30, 2021 as well as a reduction in additional paid-in capital of $1.5 million as of June 30, 2021. During the six months ended June 30, 2021, the Company paid approximately $13.7 million in principal payments on the outstanding convertible notes and approximately $ 27,000 The components of our convertible notes are as follows (in thousands): Summary of Convertible notes payable June 30, December 31, 2021 2020 Convertible notes due 2022 $ 13,689 $ 13,689 Unamortized debt discount / debt issuance costs (20) (4,112) Less principal payments (13,661) - Less current portion of long-term debt (4) (2,431) Convertible debt, long-term, net of discount and issuance costs $ 4 $ 7,146 The discounts on the convertible notes are being amortized to interest expense, using the effective interest method over the term of the convertible notes. Interest expense recognized related to the discount was approximately $ 575,000 1.6 PPP Loan On May 4, 2020, the Company qualified for and received a loan pursuant to the Paycheck Protection Program, a program implemented by the U.S. Small Business Administration under the Coronavirus Aid, Relief, and Economic Security Act, from a qualified lender (the “PPP Lender”), for an aggregate principal amount of approximately $ 147,000 1.0

7. Stockholders_ Equity

7. Stockholders’ Equity	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
7. Stockholders’ Equity	7. Stockholders’ Equity Preferred Stock The Company is authorized to issue 10,000,000 0.001 No Common Stock The Company has authorized 240,000,000 120,000,000 Warrants September 2020 Warrants The September 2020 Warrants were initially exercisable for 6,648,750 0.84 March 9, 2021 During the six months ended June 30, 2021, September 2020 Warrants were exercised for 5.6 4.7 960,000 0.84 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 February 27, 2020 During the six months ended June 30, 2021, August 2019 Warrants for 1.3 2.4 900,000 1.78 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 $0.2957 per share. The most recent adjustment to the exercise price (from $0.60 to $0.2957 per share) occurred during the three months ended September 30, 2020 as a result of the announcement of the offerings pursuant to the 2020 Securities Purchase Agreement. The Series A Warrants were immediately exercisable upon issuance and will expire on January 31, 2024. During the six months ended June 30, 2021 and 2020, Series A Warrants for 0.5 million and 0 shares of common stock, respectively, were exercised for approximately $ 0.1 million and $ 0 , respectively. As of June 30, 2021, Series A Warrants exercisable for 0.3 0.2957 per share A summary of warrant activity during the six months ended June 30, 2021 is as follows (share amounts in thousands): Summary of Warrant Activity Weighted- Weighted- Average Average Remaining Exercise Contractual Life Warrants Price (in years) Outstanding as of December 31, 2020 10,066 $ 1.84 4.4 Issued - $ - Exercised (7,431) $ 0.98 Cancelled - $ - Outstanding as of June 30, 2021 2,635 $ 4.29 3.2 Exercisable as of June 30, 2021 2,635 $ 4.29 3.2 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.

8. Stock-based Compensation

8. Stock-based Compensation	6 Months Ended
	Jun. 30, 2021
Share-based Payment Arrangement [Abstract]
8. Stock-based Compensation	8. 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 to four years and have a maximum term of ten years from the date of grant. As of June 30, 2021, an aggregate of 10,878,019 1.6 During the six months ended June 30, 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. Vesting of this award is subject to the Company achieving certain performance criteria established at the grant date and the individual fulfilling a service condition (continued employment). As of June 30, 2021, none of the performance conditions had been satisfied. The Company does not believe that the achievement of the performance criteria is probable at this time and therefore has not recognized any compensation expense during the six months ended June 30, 2021. Compensation expense will be recognized only once the performance condition is probable of being achieved and only for the cumulative amount related to the service condition that has been fulfilled. 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 on or prior to each such January 1. During the six months ended June 30, 2021, the Company sold 40,518 On July 28, 2019, the Compensation Committee of the Board of Directors (the “Compensation Committee”) of the Company 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 six months ended June 30, 2021, the Company granted 304,621 1,755,379 4.20 10 25 During the six months ended June 30, 2021, the Company also granted 64,000 1.35 10 12 The fair value of stock option grants are 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 the historical volatility of a publicly traded set of peer companies. 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 six months ended June 30, 2021, 43,805 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 six months ended June 30, 2021: Schedule of Valuation Assumptions for Stock Options Six Months Ended June 30, 2021 Risk-free interest rate 0.5 1.2 Volatility 120 125 Dividend yield - Expected term (years) 5 6 Weighted-average fair value $ 3.62 A summary of stock option activity during the six months ended June 30, 2021 is as follows (share amounts in thousands): Summary of Stock Option Activity Weighted- Weighted- Average Total Average Remaining Aggregate Stock Exercise Contractual Intrinsic Options Price Life (in years) Value Outstanding as of December 31, 2020 5,120 $ 1.97 Granted 2,124 4.11 Exercised (45) 1.65 Cancelled - - Outstanding as of June 30, 2021 7,199 $ 2.61 9.0 $ 7,263 Vested and expected to vest as of June 30, 2021 7,199 $ 2.61 9.0 $ 7,263 Exercisable as of June 30, 2021 1,599 $ 3.70 8.6 $ 2,037 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): Schedule of Stock-Based Compensation Expense Three Months Ended Six Months Ended June 30, June 30, 2021 2020 2021 2020 Research and development $ 222 $ 62 $ 358 $ 130 General and administrative 815 279 1,384 522 $ 1,037 $ 341 $ 1,742 $ 652

9. Leases

9. Leases	6 Months Ended
	Jun. 30, 2021
Leases
9. Leases	9. Leases In March 2019, the Company entered into a nine-month office space rental agreement for two office spaces for its headquarters at 300 Park Avenue, New York, NY, which was subsequently extended for an additional twelve-month term. The rental agreement provided for a base rent of approximately $9,000 per month. In November 2020, the Company returned one of the office spaces and further extended this rental agreement for one of the office spaces for an additional twelve-months for a base rent of approximately $3,800 per month. In March 2021, the Company was notified that the counterparty’s right to occupy the space at 300 Park Avenue, New York, NY was terminating, and the Company was required to vacate by March 26, 2021. The Company vacated the premises and has advised the counterparty that it is in breach of this rental agreement and therefore, the Company has no further obligations thereunder. In March 2021, the Company entered into an eighteen-month office space rental agreement for its headquarters at 300 Park Avenue, New York, NY, expiring July 2022. The rental agreement contains a base rent of approximately $4,000 per month. This agreement includes one or more renewal options. 63,000 63,000 12,000 51,000 At June 30, 2021, future minimum lease payments for operating leases with non-cancelable terms of more than one year were as follows (in thousands): Schedule of future minimum operating lease payments Operating Leases Remaining Period Ended December 31, 2021 $ 27 Year Ended December 31, 2022 40 Total 67 Less present value discount (4) Operating lease liabilities $ 63 In March 2021, the Company entered into a new operating lease, resulting in the Company recognizing an operating lease liability of approximately $74,000 based on the present value of the minimum rental payments. The Company also recognized corresponding ROU assets of approximately $74,000. As the Company’s lease does not provide an implicit rate, the Company uses an incremental borrowing rate based on the information available at the transition date and commencement date in determining the present value of lease payments. Operating lease expense was $ 13,000 1,000 The tables below present information regarding the Company's lease assets and liabilities (in thousands, except years and percentages): Schedule of assets and liabilities, leases June 30, 2021 Assets: Operating lease right-of-use-assets $ 63 Liabilities: Current Operating 51 Long-term Operating 12 Operating lease liabilities $ 63 June 30, 2021 Weighted-average remaining lease term – operating leases (in years) 1.3 Weighted-average discount rate – operating leases 8.0% For the three and six months ended June 30, 2021, rent expense totaled approximat ely $ 8,000 and $ 25,000 , respectively. For the three and six months ended June 30, 2020, rent expense totaled approximately $ 30,000 and $ 74,000

10. Commitments and Contingenci

10. Commitments and Contingencies	6 Months Ended
	Jun. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
10. Commitments and Contingencies	10. Commitments and Contingencies 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 June 30, 2021, there was no material litigation against the Company.

3. Significant Accounting Pol_2

3. Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
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, 2020 included in the Company’s Annual Report on Form 10-K (“Annual Report”) filed with the SEC on March 11, 2021. 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, 2020 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 common stock 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. 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 (in thousands): Schedule of Fair Value Hierarchy Assets and Liabilities Fair Value Measurements as of June 30, 2021 (Level 1) (Level 2) (Level 3) Total Assets Cash $ 87,200 $ - $ - $ 87,200 Liabilities Warrant liabilities, at fair value $ - $ - $ 733 $ 733 Fair Value Measurements as of December 31, 2020 (Level 1) (Level 2) (Level 3) Total Assets Cash $ 15,662 $ - $ - $ 15,662 Liabilities Warrant liabilities, at fair value $ - $ - $ 1,062 $ 1,062 There were no transfers between fair value measurement levels during the six months ended June 30, 2021.
warrant liabilities	The Company’s warrant liabilities The common stock warrant liabilities were 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 June 30, 2021: Summary of Fair Value Measurements Valuation Assumptions Six Months Ended June 30, 2021 Risk-free interest rate 0.37% Volatility 119.55% Dividend yield - Expected term (in years) 2.57 Weighted-average fair value $ 2.43 The following table is a reconciliation for the common stock warrant liabilities measured at fair value using Level 3 unobservable inputs (in thousands): Schedule of Fair Value Level 3 Reconciliation Warrant liabilities Balance as of December 31, 2020 $ 1,062 Warrant liability reclassified to stockholders' equity (1,155) Change in fair value measurement of warrant liability 826 Balance as of June 30, 2021 $ 733
Stock-based Compensation	Stock-based Compensation The Company expenses stock-based compensation to employees, non-employees and board members over the requisite service period for the entire award, except for performance condition awards where vesting is subject to the Company achieving certain performance criteria, based on the estimated grant-date fair value of the awards and forfeitures rates. Compensation costs for performance condition awards will be recognized when the achievement of the performance criteria is probable. 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.
Leases	Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in operating lease right-of-use (“ROU”) asset, operating lease liability, current and operating lease liability, long-term in the Company’s condensed consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liability represents its obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the commencement date based on the present value of the lease payments over the lease term. As the Company’s leases do not provide an implicit rate, the Company uses an incremental borrowing rate based on the information available at the transition date and commencement date in determining the present value of lease payments. This is the rate the Company would have to pay if it borrowed on a collateralized basis over a similar term to each lease. The operating lease ROU asset also includes any lease payments made and excludes lease incentives. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term.
Net Loss Per Share	Net Loss Per Share Basic loss per share is computed by dividing net 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. In computing the basic and diluted net loss per share applicable to common stockholders, the weighted average number of shares remains the same for both calculations due to the fact that when a net loss exists, dilutive shares are not included in the calculation as the impact is anti-dilutive. The following potentially dilutive securities outstanding for the three and six months ended June 30, 2021 and 2020 have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive (in thousands): Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Three and Six Months Ended June 30, 2021 2020 Outstanding stock options 7,199 4,925 Restricted stock units 2,400 67 Outstanding warrants 2,635 3,584 Convertible debt 17 - 12,251 8,576 Amounts in the table reflect the common stock equivalents of the noted instruments.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In December 2019, the FASB issued Accounting Standards Update The Company adopted ASU 2019-12 effective January 1, 2021. The adoption of ASU 2019-12 did not have a material effect on the Company’s financial statements. In August 2020, the FASB issued ASU 2020-06: Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity. 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 fiscal years beginning after December 15, 2021, 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 is evaluating the impact of ASU 2020-06 on its consolidated financial statements and related disclosures.

3. Significant Accounting Pol_3

3. Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Schedule of Fair Value Hierarchy Assets and Liabilities	Schedule of Fair Value Hierarchy Assets and Liabilities Fair Value Measurements as of June 30, 2021 (Level 1) (Level 2) (Level 3) Total Assets Cash $ 87,200 $ - $ - $ 87,200 Liabilities Warrant liabilities, at fair value $ - $ - $ 733 $ 733 Fair Value Measurements as of December 31, 2020 (Level 1) (Level 2) (Level 3) Total Assets Cash $ 15,662 $ - $ - $ 15,662 Liabilities Warrant liabilities, at fair value $ - $ - $ 1,062 $ 1,062
Summary of Fair Value Measurements Valuation Assumptions	The following assumptions were used in determining the fair value of the warrant liabilities valued using the Black-Scholes option pricing model as of June 30, 2021: Summary of Fair Value Measurements Valuation Assumptions Six Months Ended June 30, 2021 Risk-free interest rate 0.37% Volatility 119.55% Dividend yield - Expected term (in years) 2.57 Weighted-average fair value $ 2.43
Schedule of Fair Value Level 3 Reconciliation	The following table is a reconciliation for the common stock warrant liabilities measured at fair value using Level 3 unobservable inputs (in thousands): Schedule of Fair Value Level 3 Reconciliation Warrant liabilities Balance as of December 31, 2020 $ 1,062 Warrant liability reclassified to stockholders' equity (1,155) Change in fair value measurement of warrant liability 826 Balance as of June 30, 2021 $ 733
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following potentially dilutive securities outstanding for the three and six months ended June 30, 2021 and 2020 have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive (in thousands): Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Three and Six Months Ended June 30, 2021 2020 Outstanding stock options 7,199 4,925 Restricted stock units 2,400 67 Outstanding warrants 2,635 3,584 Convertible debt 17 - 12,251 8,576

6. Debt (Tables)

6. Debt (Tables)	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Summary of Convertible notes payable	The components of our convertible notes are as follows (in thousands): Summary of Convertible notes payable June 30, December 31, 2021 2020 Convertible notes due 2022 $ 13,689 $ 13,689 Unamortized debt discount / debt issuance costs (20) (4,112) Less principal payments (13,661) - Less current portion of long-term debt (4) (2,431) Convertible debt, long-term, net of discount and issuance costs $ 4 $ 7,146

7. Stockholders_ Equity (Tables

7. Stockholders’ Equity (Tables)	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
Summary of Warrant Activity	A summary of warrant activity during the six months ended June 30, 2021 is as follows (share amounts in thousands): Summary of Warrant Activity Weighted- Weighted- Average Average Remaining Exercise Contractual Life Warrants Price (in years) Outstanding as of December 31, 2020 10,066 $ 1.84 4.4 Issued - $ - Exercised (7,431) $ 0.98 Cancelled - $ - Outstanding as of June 30, 2021 2,635 $ 4.29 3.2 Exercisable as of June 30, 2021 2,635 $ 4.29 3.2

8. Stock-based Compensation (Ta

8. Stock-based Compensation (Tables)	6 Months Ended
	Jun. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Valuation Assumptions for Stock Options	The following assumptions were used in determining the fair value of the stock options granted during the six months ended June 30, 2021: Schedule of Valuation Assumptions for Stock Options Six Months Ended June 30, 2021 Risk-free interest rate 0.5 1.2 Volatility 120 125 Dividend yield - Expected term (years) 5 6 Weighted-average fair value $ 3.62
Summary of Stock Option Activity	A summary of stock option activity during the six months ended June 30, 2021 is as follows (share amounts in thousands): Summary of Stock Option Activity Weighted- Weighted- Average Total Average Remaining Aggregate Stock Exercise Contractual Intrinsic Options Price Life (in years) Value Outstanding as of December 31, 2020 5,120 $ 1.97 Granted 2,124 4.11 Exercised (45) 1.65 Cancelled - - Outstanding as of June 30, 2021 7,199 $ 2.61 9.0 $ 7,263 Vested and expected to vest as of June 30, 2021 7,199 $ 2.61 9.0 $ 7,263 Exercisable as of June 30, 2021 1,599 $ 3.70 8.6 $ 2,037
Schedule of Stock-Based Compensation Expense	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): Schedule of Stock-Based Compensation Expense Three Months Ended Six Months Ended June 30, June 30, 2021 2020 2021 2020 Research and development $ 222 $ 62 $ 358 $ 130 General and administrative 815 279 1,384 522 $ 1,037 $ 341 $ 1,742 $ 652

9. Leases (Tables)

9. Leases (Tables)	6 Months Ended
	Jun. 30, 2021
Leases
Schedule of future minimum operating lease payments	At June 30, 2021, future minimum lease payments for operating leases with non-cancelable terms of more than one year were as follows (in thousands): Schedule of future minimum operating lease payments Operating Leases Remaining Period Ended December 31, 2021 $ 27 Year Ended December 31, 2022 40 Total 67 Less present value discount (4) Operating lease liabilities $ 63
Schedule of assets and liabilities, leases	The tables below present information regarding the Company's lease assets and liabilities (in thousands, except years and percentages): Schedule of assets and liabilities, leases June 30, 2021 Assets: Operating lease right-of-use-assets $ 63 Liabilities: Current Operating 51 Long-term Operating 12 Operating lease liabilities $ 63 June 30, 2021 Weighted-average remaining lease term – operating leases (in years) 1.3 Weighted-average discount rate – operating leases 8.0%

2. Liquidity (Details Narrative

2. Liquidity (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2020	May 24, 2021	Jan. 28, 2021
Affiliate, Collateralized Security [Line Items]
Cash received from stock sale	$ 64,476	$ 97,957	$ 8,850
Financing available under Form S-3 shelf registration statement	$ 95,100	$ 95,100
May 242021 [Member]
Affiliate, Collateralized Security [Line Items]
Number of shares of common stock issued		22,258,066
Shares Issued, Price Per Share				$ 3.10
Cash received from stock sale		$ 64,500
Offering proceeds used to partially repay certain convertible promissory notes		$ 7,300
January 282021 [Member]
Affiliate, Collateralized Security [Line Items]
Number of shares of common stock issued		17,530,488
Shares Issued, Price Per Share					$ 2.05
Cash received from stock sale		$ 33,500
Offering proceeds used to partially repay certain convertible promissory notes		$ 3,800

Schedule of Fair Value Hierarch

Schedule of Fair Value Hierarchy Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Assets [Abstract]
Cash	$ 87,200	$ 15,662	$ 5,854	$ 10,261
Fair Value, Recurring [Member]
Assets [Abstract]
Cash	87,200	15,662
Fair Value, Recurring [Member] | Warrant [Member]
Liabilities [Abstract]
Warrant liabilities, at fair value	733	1,062
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Assets [Abstract]
Cash	87,200	15,662
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Warrant [Member]
Liabilities [Abstract]
Warrant liabilities, at fair value
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Assets [Abstract]
Cash
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Warrant [Member]
Liabilities [Abstract]
Warrant liabilities, at fair value
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Assets [Abstract]
Cash
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Warrant [Member]
Liabilities [Abstract]
Warrant liabilities, at fair value	$ 733	$ 1,062

Summary of Fair Value Measureme

Summary of Fair Value Measurements Valuation Assumptions (Details) - Fair Value, Inputs, Level 3 [Member] - Warrant [Member]	6 Months Ended
	Jun. 30, 2021$ / shares
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Risk-free interest rate	0.37%
Volatility	11955.00%
Dividend yield (in percent)
Expected term (in years)	2 years 6 months 25 days
Weighted average fair value (USD per share)	$ 2.43

Schedule of Fair Value Level 3

Schedule of Fair Value Level 3 Reconciliation (Details) - Fair Value, Inputs, Level 3 [Member] - Warrant [Member] $ in Thousands	6 Months Ended
	Jun. 30, 2021USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Balance as of December 31, 2020	$ 1,062
Warrant liability reclassified to stockholders' equity	(1,155)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	826
Balance as of June 30, 2021	$ 733

Schedule of Antidilutive Securi

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded	12,251,000	8,576,000
Share-based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded	7,199,000	4,925,000
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded	2,400,000	67,000
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded	2,635,000	3,584,000
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded	17,000

4. Common Stock Offerings (Deta

4. Common Stock Offerings (Details Narrative) - USD ($)

1 Months Ended

3 Months Ended

5 Months Ended

6 Months Ended

Dec. 31, 2020

Sep. 30, 2020

May 31, 2020

Mar. 31, 2020

Feb. 28, 2020

Jan. 31, 2020

Jun. 30, 2021

Sep. 30, 2020

Jun. 30, 2021

Jun. 30, 2020

May 24, 2021

Jan. 28, 2021

Sep. 09, 2020

Mar. 16, 2020

Feb. 19, 2020

Feb. 13, 2020

Business Acquisition [Line Items]

Cash received from stock sale

$ 64,476,000

$ 97,957,000

$ 8,850,000

December 2020 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

1,112,219

Cash received from stock sale

$ 10,900,000

September 42020 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

8,865,000

Cash received from stock sale

$ 6,400,000

Warrant terms and provisions

The Company also issued to the investors 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 have an exercise price of $0.84 per share of common stock, became exercisable beginning on March 9, 2021 and will expire on March 9, 2026.

Shares Issued, Price Per Share

$ 0.79

May 112020 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

300,000

Consulting expense

$ 431,000

May 242021 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

22,258,066

Cash received from stock sale

$ 64,500,000

Shares Issued, Price Per Share

$ 3.10

Offering proceeds used to partially repay certain convertible promissory notes

$ 7,300,000

January 282021 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

17,530,488

Cash received from stock sale

$ 33,500,000

Shares Issued, Price Per Share

$ 2.05

Offering proceeds used to partially repay certain convertible promissory notes

$ 3,800,000

March 162020 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

7,500,000

Cash received from stock sale

$ 4,000,000

Shares Issued, Price Per Share

$ 0.60

February 132020 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

6,666,667

Cash received from stock sale

$ 4,800,000

Shares Issued, Price Per Share

$ 0.75

February 192020 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

999,999

Shares Issued, Price Per Share

$ 0.75

January 22020 [Member]

Business Acquisition [Line Items]

Number of shares of common stock issued

1,809,845

January 242019 [Member]

Business Acquisition [Line Items]

Warrant terms and provisions

Pursuant to the Purchase Agreement, STI (i) issued and sold to the Investors an aggregate of 2,374,672 shares of STI’s common stock which converted pursuant to the exchange ratio in the Merger into the right to receive 1,829,407 shares of the Company’s common stock and (ii) issued warrants representing the right to acquire 1,463,519 shares of common stock at a price per share of $4.15, subject to adjustment as provided therein (the “Series A Warrants”), most recently adjusted to a price per share of $0.2957 per share, and additional warrants initially representing the right to acquire no shares of common stock at a price per share of $0.001, subject to adjustment as provided therein (the “Series B Warrants” together with the Series A Warrants, the “Investor Warrants”), for aggregate gross proceeds of $18.0 million, or $16.5 million net of financing fees. The terms of the Investor Warrants included certain provisions that could result in adjustments to both the number of warrants issued and the exercise price of each warrant, which resulted in the warrants being classified as a liability upon issuance (see Note 7). The Investor Warrants were recorded at fair value of $21.5 million upon issuance and given that the liability exceeded the proceeds received, a loss of $5.0 million was recognized.

March 72019 [Member]

Business Acquisition [Line Items]

Warrant terms and provisions

On March 7, 2019, the Company entered into Amendment Agreements (collectively, the “Amendment Agreements”) with each Investor amending: (i) the Purchase Agreement, (ii) the Series A Warrants, and (iii) the Series B Warrants. The Amendment Agreements, among other things, fixed the aggregate number of shares of common stock issued and issuable pursuant to the Series A Warrants at 3,629,023 (none of which were exercised as of March 7, 2019). The terms of the Investor Warrants continue to include certain provisions that could result in a future adjustment to the exercise price of the Investor Warrants and accordingly, they continue to be classified as a liability after the Amendment Agreements.

Series A Warrants unexercised

300,000

300,000

5. License Agreements (Details

5. License Agreements (Details Narrative) - USD ($)

1 Months Ended

3 Months Ended

6 Months Ended

Jan. 31, 2022

Sep. 30, 2021

Jun. 30, 2021

Feb. 28, 2021

Jan. 31, 2021

Jul. 31, 2020

Apr. 30, 2020

Feb. 29, 2020

Jan. 31, 2020

Oct. 31, 2019

Aug. 31, 2019

Jun. 30, 2019

Mar. 31, 2019

Feb. 28, 2019

Jan. 31, 2019

May 31, 2018

Mar. 31, 2018

Sep. 30, 2016

Jun. 30, 2021

Jun. 30, 2020

Jun. 30, 2019

Mar. 31, 2019

Jun. 30, 2021

Jun. 30, 2020

Business Combination, Separately Recognized Transactions [Line Items]

Research and development expense

$ 4,308,000

$ 1,444,000

$ 18,420,000

$ 5,137,000

Licensefrom Ligand Pharmaceuticals [Member]

Business Combination, Separately Recognized Transactions [Line Items]

License agreement description

On September 21, 2016, the Company entered into a License Agreement (the “License Agreement”) with Ligand Pharmaceuticals Incorporated (“Ligand”), Neurogen Corporation and CyDex Pharmaceuticals, Inc. (collectively, the “Licensors”), pursuant to which, among other things, the Licensors granted to the Company an exclusive, perpetual, irrevocable, worldwide, royalty-bearing, nontransferable right and license under (i) patents related to a product known as Aplindore, which is now known as SLS-006, acetaminophen (as it may have been or may be modified for use in a product to be administered by any method in any form including, without limitation injection and intravenously, the sole active pharmaceutical ingredient of which is acetaminophen), which is now known as SLS-012, an H3 receptor antagonist, which is now known as SLS-010, and either or both of the Licensors’ two proprietary CRTh2 antagonists, which are now known collectively as SLS-008 (collectively, the “Licensed Products”), and (ii) copyrights, trade secrets, moral rights and all other intellectual and proprietary rights related thereto. The Company is obligated to use commercially reasonable efforts to (a) develop the Licensed Products, (b) obtain regulatory approval for the Licensed Products in the European Union (either in its entirety or including at least one of France, Germany or, if at the time the United Kingdom is a member of the European Union, the United Kingdom), the United Kingdom, if at the time the United Kingdom is not a member of the European Union, Japan or the People’s Republic of China (each, a “Major Market”) or the United States, and (c) commercialize the Licensed Products in each country where regulatory approval is obtained. The Company has the exclusive right and sole responsibility and decision-making authority to research and develop any Licensed Products and to conduct all clinical trials and non-clinical studies the Company believes appropriate to obtain regulatory approvals for commercialization of the Licensed Products. The Company also has the exclusive right and sole responsibility and decision-making authority to commercialize any of the Licensed Products.

Shares of common stock issued

801,253

Research and development expense

$ 2,200,000

Milestone payments accrued

$ 0

0

0

Assetsfrom Vyera Pharmaceuticals [Member]

Business Combination, Separately Recognized Transactions [Line Items]

License agreement description

On March 6, 2018, the Company entered into the Vyera Agreement with Vyera, pursuant to which the Company acquired the assets (the “Vyera Assets”) and liabilities (the “Vyera Assumed Liabilities”), of Vyera related to TUR-002 (intranasal ketamine), which is now known as SLS-002. The Company is obligated to use commercially reasonable efforts to seek regulatory approval in the United States for and commercialize SLS-002

Shares of common stock issued

1,809,845

191,529

Milestone payments accrued

0

0

0

Non-refundable cash payment

$ 150,000

$ 150,000

$ 1,000,000

Cash payments agreed to in Amendment to the Asset Purchase Agreement

$ 1,000,000

$ 1,000,000

$ 750,000

$ 750,000,000

Cash payments for lower royalty percentage on potential net sales of SLS-002

$ 3,000,000

3,000,000

$ 3,000,000

Weg License Agreement [Member]

Business Combination, Separately Recognized Transactions [Line Items]

License agreement description

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 an NDA 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 and $0.125 million on January 2, 2021. As further consideration, the Company agreed to pay Dr. Weg certain milestone payments consisting of (i) $0.1 million and shares of common stock equal to $0.15 million divided by the closing sales price of the Company’s common stock upon the issuance of the first patent directed to an anxiety indication, (ii) $0.5 million after the locking of the database and unblinding the data for the statistically significant readout of a Phase III trial of an intranasal racemic ketamine product that has been conducted for the submission under an NDA or equivalent seeking regulatory approval in the United States, the United Kingdom, France, Germany, Italy, Spain, China or Japan, or seeking regulatory approval from the EMA in the EU, for such product (the “Milestone Product”), (iii) $3.0 million upon FDA approval of an NDA for the Milestone Product, (iv) $2.0 million upon regulatory approval by the EMA for the Milestone Product, and (v) $1.5 million upon regulatory approval in Japan for the Milestone Product; provided, however, that the maximum amount to be paid by the Company under milestones (i)-(v) will be $6.6 million. The Company will also pay to Dr. Weg a royalty percentage equal to 2.25% on the sale of each product containing ketamine in any dosage

Milestone payments accrued

0

0

0

Non-refundable cash payment

$ 200,000

$ 125,000

$ 100,000

Assetsfrom Bioblast Pharma [Member]

Business Combination, Separately Recognized Transactions [Line Items]

License agreement description

On February 15, 2019, the Company entered into an Asset Purchase Agreement (the “Bioblast Asset Purchase Agreement”) with Bioblast. Pursuant to the Bioblast Asset Purchase Agreement, the Company acquired all of the assets of Bioblast relating to a therapeutic platform known as Trehalose (the “Bioblast Asset Purchase”). The Company paid to Bioblast $1.5 million in February 2019 and an additional $2.0 million in February 2020. Accordingly, the Company recognized a $3.5 million charge to research and development expense during the three months ended March 31, 2019. Under the terms of the Bioblast Asset Purchase Agreement, the Company agreed to pay additional consideration to Bioblast upon the achievement of certain milestones in the future, as follows: (i) within 15 days following the completion of the Company’s first Phase II(b) clinical trial of Trehalose satisfying certain criteria, the Company will pay to Bioblast $8.5 million; and (ii) within 15 days following the approval for commercialization by the FDA or the Health Products and Food Branch of Health Canada of the first NDA or New Drug Submission, respectively, of Trehalose filed by the Company or its affiliates, the Company will pay to Bioblast $8.5 million. In addition, the Company agreed to pay Bioblast a cash royalty equal to 1% of the net sales of Trehalose. Under the terms of the Bioblast Asset Purchase, the Company assumed a collaborative agreement with Team Sanfilippo Foundation (“TSF”), a nonprofit medical research foundation founded by parents of children with Sanfilippo syndrome. TSF, upon approval by the FDA, planned to begin an open label, Phase II(b) clinical trial in up to 20 patients with Sanfilippo syndrome, which is now known under the study name SLS-005. The Company will provide the clinical supply of Trehalose. The terms of the Bioblast Asset Purchase Agreement entitle the Company access to all clinical data from this trial. On July 15, 2019, TSF and the Company amended the agreement whereby the Company agreed to assume responsibility for the Phase II(b)/III clinical trial and TSF agreed to provide a grant of up to $1.5 million towards the funding of the trial.

Research and development expense

3,500,000

Milestone payments accrued

0

0

0

Non-refundable cash payment

$ 2,000,000

$ 1,500,000

U C Regents License Agreement [Member]

Business Combination, Separately Recognized Transactions [Line Items]

License agreement description

On June 27, 2019, the Company entered into an exclusive license agreement (the “Duke License Agreement”) with Duke University pursuant to which the Company was granted an exclusive license to a gene therapy program targeting the regulation of the synuclein alpha (“SNCA”) gene, which encodes alpha-synuclein expression. The Company plans to study this initial approach in PD and will further evaluate the potential clinical approach in other disorders affecting the CNS. This program is now known as SLS-004. Upon entry into the Duke License Agreement, the Company paid to Duke University $0.1 million and recognized $0.1 million charge to research and development expense during the three months ended June 30, 2019. The Company agreed to pay additional consideration to Duke University upon the achievement of certain milestones in the future, as follows: (i) within 30 days following filing of an IND following the completion of preclinical studies including comprehensive validation of the platform, the Company will pay $0.1 million; (ii) within 30 days following dosing of the first patient in a Phase I clinical trial, the Company will pay $0.2 million; (iii) within 30 days following dosing of the first patient in a Phase II clinical trial, the Company will pay $0.5 million; (iv) within 30 days following dosing of the first patient in a Phase III clinical trial, the Company will pay $1.0 million; and (v) within 30 days following an NDA approval, the Company will pay $2.0 million. The Company is also obligated to pay a single digit royalty on sales of the product, if any. In addition, if the Company fails to achieve certain milestones within a specified timeframe, Duke University may terminate the agreement.

On March 7, 2019, the Company entered into an exclusive license agreement (the “UC Regents License Agreement”) with The Regents of the University of California (“The UC Regents”) pursuant to which the Company was granted an exclusive license to intellectual property owned by The UC Regents pertaining to a technology that was created by researchers at the University of California, Los Angeles (UCLA). Such technology relates to a family of rationally-designed peptide inhibitors that target the aggregation of alpha-synuclein (α-synuclein). The Company plans to study this initial approach in PD and will further evaluate the potential clinical approach in other disorders affecting the CNS. This program is now known as SLS-007. Upon entry into the UC Regents License Agreement, the Company paid to The UC Regents $0.1 million and recognized a $0.1 million charge to research and development expense during the three months ended March 31, 2019. Under the terms of the UC Regents License Agreement, the Company agreed to pay additional consideration upon the achievement of certain milestones in the future, as follows: (i) within 90 days following the completion of dosing of the first patient in a Phase I clinical trial, the Company will pay $50,000; (ii) within 90 days following dosing of the first patient in a Phase II clinical trial, the Company will pay $0.1 million; (iii) within 90 days following dosing of the first patient in a Phase III clinical trial, the Company will pay $0.3 million; (iv) within 90 days following the first commercial sales in the U.S., the Company will pay $1.0 million; (v) within 90 days following the first commercial sales in any European market, the Company will pay $1.0 million; and (vi) within 90 days following $250 million in cumulative worldwide net sales of a licensed product, the Company will pay $2.5 million. The Company is also obligated to pay a single digit royalty on sales of the product, if any. In addition, if the Company fails to achieve certain milestones within a specified timeframe, The UC Regents may terminate the agreement or reduce the Company’s license to a nonexclusive license.

Research and development expense

$ 100,000

Milestone payments accrued

0

0

0

Non-refundable cash payment

$ 100,000

Duke License Agreement [Member]

Business Combination, Separately Recognized Transactions [Line Items]

Research and development expense

$ 100,000

Milestone payments accrued

$ 0

$ 0

$ 0

Non-refundable cash payment

$ 100,000

Summary of Convertible notes pa

Summary of Convertible notes payable (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
Convertible notes due 2022	$ 13,689	$ 13,689
Unamortized debt discount / debt issuance costs	(20)	(4,112)
Less principal payments	(13,661)
Less principal payments	13,661
Less current portion of long-term debt	(4)	(2,431)
Convertible debt, long-term, net of discount and issuance costs	$ 4	$ 7,146

6. Debt (Details Narrative)

6. Debt (Details Narrative) - USD ($)	1 Months Ended		3 Months Ended	6 Months Ended
	Dec. 31, 2020	May 31, 2020	Jun. 30, 2021	Jun. 30, 2021
Short-term Debt [Line Items]
Undiscounted convertibile notes			$ 27,000	$ 27,000
Amortization of debt financing costs and discounts			575,000	1,600,000
Lind Securities Purchase Agreement [Member]
Short-term Debt [Line Items]
Description of long-term debt	On December 11, 2020, the Company entered into a Securities Purchase Agreement (the “Lind Securities Purchase Agreement”) with Lind Global Asset Management II, LLC (“Lind”) pursuant to which, among other things, on December 11, 2020, the Company issued and sold to the Investor, in a private placement transaction, in exchange for the payment by Lind of $10,000,000, (1) a convertible promissory note (the “Note”) in an aggregate principal amount of $12,000,000 (the “Principal Amount”), which will bear no interest and mature on December 11, 2022 (the “Maturity Date”), and (2) 975,000 shares of the Company’s common stock. At any time following June 11, 2021, and from time to time before the Maturity Date, the Investor had the option to convert any portion of the then-outstanding Principal Amount of the Note into shares of common stock at a price per share of $1.60, subject to adjustment for stock splits, reverse stock splits, stock dividends and similar transactions (the “Conversion Price”). Prior to June 11, 2021, the Company had the right to prepay up to sixty-six and two-thirds percent (66 2/3%) of the then-outstanding Principal Amount of the Note with no penalty. Subject to certain exceptions, the Company was 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 Note, unless waived by the Investor in advance. The Note began amortizing in June 2021 and was to amortize in eighteen monthly installments equal to the quotient of (i) the then-outstanding Principal Amount of the Note, divided by (ii) the number of months remaining until the Maturity Date. All amortization payments were to be payable solely in cash, plus a 2% premium. On June 14, 2021, the Company and Lind entered into an Acknowledgment and Termination Agreement, pursuant to which the Company agreed to issue to Lind an aggregate of 406,250 additional shares of its common stock (the “Lind Shares”) and pay Lind the remaining principal amount of $790,804 (the “Final Payment”) in full satisfaction the Company’s remaining obligations to Lind under the Note. The Company issued the Lind Shares and made the Final Payment to Lind, and the Lind Securities Purchase Agreement and the Note terminated, effective June 15, 2021. The Company recorded a loss on extinguishment of debt of $1.4 million for the issuance of the 406,250 shares during the three and six months ended June 30, 2021.
December 17 S P As [Member]
Short-term Debt [Line Items]
Description of long-term debt	On December 17, 2020, the Company entered into three separate securities purchase agreements with certain accredited investors on substantially the same terms as the Lind Securities Purchase Agreement (the “December 17 SPAs”), pursuant to which the Company sold, in private placement transactions, in exchange for the payment by the accredited investors of an aggregate of $1,138,023, (1) convertible promissory notes (the “December 17 Notes”) in an aggregate principal amount of $1,365,628, which will bear no interest and mature on December 17, 2022, and (2) an aggregate of 110,956 shares of its common stock. On December 18, 2020, the Company entered into an additional securities purchase agreement with an accredited investor on substantially the same terms as the Lind Securities Purchase Agreement (the “December 18 SPA” and, together with the December 17 SPAs, the "Subsequent Securities Purchase Agreements"), pursuant to which the Company sold, in a private placement transaction, in exchange for the payment by the accredited investor of $269,373, (1) a convertible promissory note in an aggregate principal amount of $323,247, which will bear no interest and mature on December 18, 2022 (the “December 18 Note” and, together with the December 17 Notes, the “Subsequent Notes”), and (2) 26,263 shares of the Company’s common stock. The Subsequent Securities Purchase Agreements have substantially the same terms as the Lind Securities Purchase Agreement, and the Subsequent Notes have substantially the same terms as the Note.
P P P Loan [Member]
Short-term Debt [Line Items]
Description of long-term debt		On May 4, 2020, the Company qualified for and received a loan pursuant to the Paycheck Protection Program, a program implemented by the U.S. Small Business Administration under the Coronavirus Aid, Relief, and Economic Security Act, from a qualified lender (the “PPP Lender”), for an aggregate principal amount of approximately $147,000 (the “PPP Loan”). The PPP Loan bears interest at a fixed rate of 1.0% per annum, with the first six months of interest deferred, has a term of two years, and is unsecured and guaranteed by the U.S. Small Business Administration. The principal amount of the PPP Loan is subject to forgiveness under the Paycheck Protection Program upon the Company’s request to the extent that the PPP Loan proceeds are used to pay expenses permitted by the Paycheck Protection Program, including payroll costs, covered rent and mortgage obligations and covered utility payments incurred by the Company. The Company applied for and received full forgiveness of the PPP Loan with respect to these covered expenses and recorded a gain on forgiveness of debt during the three and six months ended June 30, 2021.
Principal amount at issuance			$ 147,000	$ 147,000
Interest rate			100.00%	100.00%

Summary of Warrant Activity (De

Summary of Warrant Activity (Details) - Warrant Derivative Financial Instruments [Member]	6 Months Ended
	Jun. 30, 2021$ / sharesshares
Summary of Investment Holdings [Line Items]
Outstanding as of December 31, 2020 | shares	10,066,000
Outstanding as of December 31, 2020, weighted-average exercise price (in usd per share) | $ / shares	$ 1.84
Warrants outstanding as of December 31, 2020, weighted-average remaing contractual life (in years)	4 years 4 months 24 days
Issued | shares
Issued, warrant exercise price | $ / shares
Exercised | shares	(7,431,000)
Exercised, exercise price of warrants | $ / shares	$ 0.98
Cancelled | shares
Cancelled, exercise price of warrants | $ / shares
Outstanding as of June 30, 2021 | shares	2,635,000
Outstanding as of June 30, 2021, weighted-average exercise price (in usd per share) | $ / shares	$ 4.29
Warrants outstanding as of June 30, 2021, weighted-average remaing contractual life (in years)	3 years 2 months 12 days
Warrants exercisable as of June 30, 2021 | shares	2,635,000
Exercisable, weighted-average exercise price (in usd per share) | $ / shares	$ 4.29
Warrants exercisable as of June 30, 2021, weighted-average remaing contractual life (in years)	3 years 2 months 12 days

7. Stockholders_ Equity (Detail

7. Stockholders’ Equity (Details Narrative) - USD ($)	1 Months Ended	6 Months Ended
	Aug. 31, 2019	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Class of Warrant or Right [Line Items]
Preferred stock, authorized (in shares)		10,000,000		10,000,000
Preferred stock, per value (in usd per share)		$ 0.001		$ 0.001
Preferred stock, outstanding (in shares)		0		0
Common stock, authorized (in shares)		240,000,000		120,000,000
Proceeds from exercise of warrants		$ 7,252,000
September 2020 Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares of common stock issued	6,648,750
Warrants exercisable as of June 30, 2021		960,000
August 232019 [Member]
Class of Warrant or Right [Line Items]
Number of shares of common stock issued	4,475,000
August 2019 Warrants [Member]
Class of Warrant or Right [Line Items]
Warrants exercisable as of June 30, 2021		900,000
September 2020 Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant description		The September 2020 Warrants were initially 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.
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 0.84
Date on which warrants became exercisable		Mar. 9, 2021
Number of warrants exercised		5,600,000
Proceeds from exercise of warrants		$ 4,700,000
August 2019 Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant description		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.
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 1.78
Date on which warrants became exercisable		Feb. 27, 2020
Number of warrants exercised		1,300,000
Proceeds from exercise of warrants		$ 2,400,000
Series A Warrants [Member]
Class of Warrant or Right [Line Items]
Warrant description		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 $0.2957 per share. The most recent adjustment to the exercise price (from $0.60 to $0.2957 per share) occurred during the three months ended September 30, 2020 as a result of the announcement of the offerings pursuant to the 2020 Securities Purchase Agreement. The Series A Warrants were immediately exercisable upon issuance and will expire on January 31, 2024.
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 0.2957
Number of warrants exercised		500,000	0
Proceeds from exercise of warrants		$ 100,000	$ 0
Warrants exercisable as of June 30, 2021		300,000

Schedule of Valuation Assumptio

Schedule of Valuation Assumptions for Stock Options (Details) - Share-based Payment Arrangement, Option [Member]	6 Months Ended
	Jun. 30, 2021$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	50.00%
Risk-free interest rate, maximum	120.00%
Dividend yield
Weighted average fair value	$ 3.62
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility, minimum	120.00%
Expected term (in years)	5 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility, maximum	125.00%
Expected term (in years)	6 years

Summary of Stock Option Activit

Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, end of period (USD per share)	$ 2.61
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding as of December 31, 2020	5,120,000
Outstanding, beginning of period (USD per share)	$ 1.97
Granted	2,124,000
Granted in period (USD per share)	$ 4.11
Exercised	(45,000)
Exercised in period (USD per share)	$ 1.65
Cancelled
Cancelled (USD per share)	$ 0
Outstanding as of June 30, 2021	7,199,000
Outstanding - weighted-average remaining contractual life (in years)	9 years
Total aggregate intrinsic value shares outstanding	$ 7,263
Vested and expected to vest, end of period (shares)	7,199,000
Vested and expected to vest stock, end of period (USD per share)	$ 2.61
Weighted-average remaining contractual life (in years) of vested and expected to vest stock options	9 years
Total aggregate intrinsic value of vested or expected to vest stock options	$ 7,263
Exercisable, end of period (shares)	1,599,000
Exercisable, end of period (USD per share)	$ 3.70
Weighted-average remaining contractual life (in years) of exercisable stock options	8 years 7 months 6 days
Total aggregate intrinsic value of exercisable stock options	$ 2,037

Schedule of Stock-Based Compens

Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 1,037	$ 341	$ 1,742	$ 652
Research and Development Expense [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	222	62	358	130
General and Administrative Expense [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 815	$ 279	$ 1,384	$ 522

8. Stock-based Compensation (De

8. Stock-based Compensation (Details Narrative)	6 Months Ended
	Jun. 30, 2021$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of share-based compensation arrangement by share-based payment award	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 to four years and have a maximum term of ten years from the date of grant. As of June 30, 2021, an aggregate of 10,878,019 shares of common stock were authorized under the 2012 Plan, of which 1.6 million shares of common stock were available for future grants. Upon completion of the Merger, the Company assumed the Seelos Therapeutics, Inc. 2016 Equity Incentive Plan (the “2016 Plan”) and awards outstanding under the 2016 Plan became awards for common stock. Effective as of the Merger, no further awards may be issued under the 2016 Plan.
Share-based compensation arrangement by share-based payment award, number of shares authorized	10,878,019
Share-based compensation arrangement by share-based payment award, number of shares available for grant	1,600,000
Purchases under Employee Stock Purchase Plan percent of market price	85.00%
Stock Issued During Period, Shares, Employee Stock Ownership Plan	40,518
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of share-based compensation arrangement by share-based payment award	During the six months ended June 30, 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. Vesting of this award is subject to the Company achieving certain performance criteria established at the grant date and the individual fulfilling a service condition (continued employment). As of June 30, 2021, none of the performance conditions had been satisfied. The Company does not believe that the achievement of the performance criteria is probable at this time and therefore has not recognized any compensation expense during the six months ended June 30, 2021. Compensation expense will be recognized only once the performance condition is probable of being achieved and only for the cumulative amount related to the service condition that has been fulfilled.
Inducement Planof 2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of share-based compensation arrangement by share-based payment award	On July 28, 2019, the Compensation Committee of the Board of Directors (the “Compensation Committee”) of the Company 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.
Incentive Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period	304,621
Weighted-average exercise price per share granted in period | $ / shares	$ 4.20
Term of option grant	10 years
Vesting percentage on the first anniversary	25.00%
Non Qualified Stock Options To Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period	1,755,379
Weighted-average exercise price per share granted in period | $ / shares	$ 4.20
Term of option grant	10 years
Vesting percentage on the first anniversary	25.00%
Non Qualified Stock Options To Non Employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period	64,000
Weighted-average exercise price per share granted in period | $ / shares	$ 1.35
Term of option grant	10 years
Vesting period	12 months

Schedule of future minimum oper

Schedule of future minimum operating lease payments (Details) $ in Thousands	Jun. 30, 2021USD ($)
Leases
Remaining Period Ended December 31, 2021	$ 27
Year Ended December 31, 2022	40
Total	67
Less present value discount	(4)
Operating lease liabilities	$ 63

Schedule of assets and liabilit

Schedule of assets and liabilities, leases (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Assets:
Operating lease right-of-use-assets	$ 63
Current
Operating	51
Long-term
Operating	12
Operating lease liabilities	$ 63
Weighted-average remaining lease term – operating leases (in years)	1 year 3 months 18 days
Weighted-average discount rate – operating leases	8.00%

9. Leases (Details Narrative)

9. Leases (Details Narrative) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Lessor, Lease, Description [Line Items]
Operating lease right-of-use asset	$ 63,000		$ 63,000
Operating lease liabilities	63,000		63,000
Operating lease liability, long-term	12,000		12,000
Operating lease liability	51,000		51,000
Operating lease expense	8,000	$ 30,000	$ 25,000	$ 74,000
March 2019 Lease [Member]
Lessor, Lease, Description [Line Items]
Operating lease description			In March 2019, the Company entered into a nine-month office space rental agreement for two office spaces for its headquarters at 300 Park Avenue, New York, NY, which was subsequently extended for an additional twelve-month term. The rental agreement provided for a base rent of approximately $9,000 per month. In November 2020, the Company returned one of the office spaces and further extended this rental agreement for one of the office spaces for an additional twelve-months for a base rent of approximately $3,800 per month. In March 2021, the Company was notified that the counterparty’s right to occupy the space at 300 Park Avenue, New York, NY was terminating, and the Company was required to vacate by March 26, 2021. The Company vacated the premises and has advised the counterparty that it is in breach of this rental agreement and therefore, the Company has no further obligations thereunder.
March 2021 Lease [Member]
Lessor, Lease, Description [Line Items]
Operating lease description			In March 2021, the Company entered into an eighteen-month office space rental agreement for its headquarters at 300 Park Avenue, New York, NY, expiring July 2022. The rental agreement contains a base rent of approximately $4,000 per month. This agreement includes one or more renewal options. The lease agreement does not impose a restriction on the Company’s ability to engage in financing transactions or enter into further lease agreements. At June 30, 2021, the Company has right-of-use assets of $63,000 and a total lease liability for operating leases of $63,000, of which $12,000 is included in long-term lease liabilities and $51,000 is included in current lease liabilities.
Option to extend			This agreement includes one or more renewal options.
Operating lease right-of-use asset	63,000		$ 63,000
Operating lease liabilities	63,000		63,000
Operating lease liability, long-term	12,000		12,000
Operating lease liability	51,000		51,000
Operating lease expense	13,000		13,000
Amortization expense	$ 1,000		$ 1,000