Traws Pharma (TRAW) 10-Q 13 May 22 2022 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2022	May 02, 2022
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2022
Document Transition Report	false
Entity File Number	001-36020
Entity Registrant Name	Onconova Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	22-3627252
Entity Address, Address Line One	12 Penns Trail
Entity Address, City or Town	Newtown
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	18940
City Area Code	267
Local Phone Number	759-3680
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		20,895,563
Title of 12(b) Security	Common Stock, par value $.01 per share
Trading Symbol	ONTX
Security Exchange Name	NASDAQ
Entity Central Index Key	0001130598
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 50,767,000	$ 55,070,000
Receivables	27,000	28,000
Prepaid expenses and other current assets	583,000	332,000
Total current assets	51,377,000	55,430,000
Property and equipment, net	35,000	38,000
Other non-current assets	10,000	10,000
Total assets	51,422,000	55,478,000
Current liabilities:
Accounts payable	3,122,000	2,757,000
Accrued expenses and other current liabilities	2,600,000	3,132,000
Deferred revenue	226,000	226,000
Total current liabilities	5,948,000	6,115,000
Deferred revenue, non-current	3,187,000	3,243,000
Total liabilities	9,135,000	9,358,000
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.01 par value, 5,000,000 shares authorized, none issued and outstanding at March 31, 2022 and December 31, 2021
Common stock, $0.01 par value, 125,000,000 shares authorized, 20,895,563 shares issued and outstanding at March 31, 2022 and December 31, 2021	209,000	209,000
Additional paid in capital	490,940,000	490,644,000
Accumulated deficit	(448,841,000)	(444,719,000)
Accumulated other comprehensive loss	(21,000)	(14,000)
Total stockholders' equity	42,287,000	46,120,000
Total liabilities and stockholders' equity	$ 51,422,000	$ 55,478,000

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Condensed Consolidated Balance Sheets
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	20,895,563	20,895,563
Common stock, shares outstanding	20,895,563	20,895,563

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Condensed Consolidated Statements of Operations
Revenue	$ 56,000	$ 56,000
Operating expenses:
General and administrative	2,186,000	2,217,000
Research and development	2,002,000	1,937,000
Total operating expenses	4,188,000	4,154,000
Loss from operations	(4,132,000)	(4,098,000)
Change in fair value of warrant liability		(636,000)
Other income, net	10,000	19,000
Net loss	$ (4,122,000)	$ (4,715,000)
Net loss per share, basic (in dollars per share)	$ (0.20)	$ (0.32)
Net loss per share, diluted (in dollars per share)	$ (0.20)	$ (0.32)
Basic weighted average shares outstanding (in shares)	20,904,085	14,616,139
Diluted weighted average shares outstanding (in shares)	20,904,085	14,616,139

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Condensed Consolidated Statements of Comprehensive Loss
Net loss	$ (4,122,000)	$ (4,715,000)
Other comprehensive loss, net of tax:
Foreign currency translation adjustments, net	(7,000)	(16,000)
Other comprehensive loss, net of tax	(7,000)	(16,000)
Comprehensive loss	$ (4,129,000)	$ (4,731,000)

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity (Deficit) - USD ($)	Common Stock	Additional Paid in Capital	Accumulated deficit	Accumulated other comprehensive income (loss)	Total
Balance at Dec. 31, 2020	$ 124,000	$ 434,593,000	$ (428,556,000)	$ 14,000	$ 6,175,000
Balance (in shares) at Dec. 31, 2020	12,396,219
Increase (Decrease) in Stockholders' Equity (Deficit)
Net loss			(4,715,000)		(4,715,000)
Other comprehensive loss				(16,000)	(16,000)
Exercise of stock options		17,000			17,000
Exercise of stock options (in shares)	2,867
Stock-based compensation		65,000			65,000
Issuance of common stock, net	$ 32,000	35,115,000			35,147,000
Issuance of common stock, net (in shares)	3,220,075
Issuance of common stock upon exercise of warrants	$ 2,000	478,000			480,000
Issuance of common stock upon exercise of warrants (in shares)	160,000
Balance at Mar. 31, 2021	$ 158,000	470,268,000	(433,271,000)	(2,000)	37,153,000
Balance (in shares) at Mar. 31, 2021	15,779,161
Balance at Dec. 31, 2021	$ 209,000	490,644,000	(444,719,000)	(14,000)	$ 46,120,000
Balance (in shares) at Dec. 31, 2021	20,895,563				20,895,563
Increase (Decrease) in Stockholders' Equity (Deficit)
Net loss			(4,122,000)		$ (4,122,000)
Other comprehensive loss				(7,000)	(7,000)
Stock-based compensation		296,000			296,000
Balance at Mar. 31, 2022	$ 209,000	$ 490,940,000	$ (448,841,000)	$ (21,000)	$ 42,287,000
Balance (in shares) at Mar. 31, 2022	20,895,563				20,895,563

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Net loss	$ (4,122,000)	$ (4,715,000)
Adjustment to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,000	3,000
Change in fair value of warrant liabilities		636,000
Stock compensation expense	296,000	65,000
Changes in assets and liabilities:
Receivables	1,000	(1,000)
Prepaid expenses and other current assets	(251,000)	115,000
Accounts payable	365,000	(845,000)
Accrued expenses and other current liabilities	(532,000)	(1,850,000)
Deferred revenue	(56,000)	(56,000)
Net cash used in operating activities	(4,296,000)	(6,648,000)
Financing activities:
Proceeds from the sale of common stock and warrants, net of costs		35,147,000
Proceeds from the exercise of common warrants		480,000
Proceeds from the exercise of stock options		17,000
Net cash provided by financing activities		35,644,000
Effect of foreign currency translation on cash	(7,000)	(16,000)
Net increase (decrease) in cash and cash equivalents	(4,303,000)	28,980,000
Cash and cash equivalents at beginning of period	55,070,000	19,025,000
Cash and cash equivalents at end of period	$ 50,767,000	$ 48,005,000

Nature of Business

Nature of Business	3 Months Ended
	Mar. 31, 2022
Nature of Business
Nature of Business	1. Nature of Business ​ The Company ​ Onconova Therapeutics, Inc. (the “Company”) was incorporated in the State of Delaware on December 22, 1998 and commenced operations on January 1, 1999. The Company’s headquarters are located in Newtown, Pennsylvania. The Company is a clinical-stage biopharmaceutical company focused on discovering and developing novel products for patients with cancer. The Company has proprietary targeted anti-cancer agents designed to disrupt specific cellular pathways that are important for cancer cell proliferation. The Company believes that the product candidates in its pipeline have the potential to be efficacious in a variety of cancers with unmet medical need. The Company has the following two clinical-stage programs: 1. narazaciclib (ON 123300), a multi-kinase inhibitor in solid tumors; and 2. oral rigosertib alone or in combination with PD-1 inhibitors for treatment of KRAS-mutated solid tumors. During 2012, Onconova Europe GmbH was established as a wholly owned subsidiary of the Company for the purpose of further developing business in Europe. ​ On May 20, 2021, the Company amended its certificate of incorporation to decrease the number of authorized shares of common stock par value $0.01 per share from 250,000,000 to 125,000,000, and to effect a one-for-fifteen one-for-fifteen ​ ​ Liquidity ​ The Company has incurred recurring operating losses since inception. For the three months ended March 31, 2022, the Company incurred a net loss of $4,122,000 and as of March 31, 2022 the Company had generated an accumulated deficit of $448,841,000. The Company anticipates operating losses to continue for the foreseeable future due to, among other things, costs related to research, development of its product candidates and its preclinical programs, strategic alliances and its administrative organization. At March 31, 2022, the Company had cash and cash equivalents of $50,767,000 ​ The Company has and may continue to delay, scale-back, or eliminate certain of its research and development activities and other aspects of its operations until such time as the Company is successful in securing additional funding. The Company is exploring various dilutive and non-dilutive sources of funding, including equity financings, strategic alliances, business development and other sources. The future success of the Company is dependent upon its ability to obtain additional funding. There can be no assurance, however, that the Company will be successful in obtaining such funding in sufficient amounts, on terms acceptable to the Company, or at all. The Company believes that its cash and cash equivalents will be sufficient to fund its ongoing trials and business operations for more than twelve months from the date of this filing. ​ COVID-19 ​ While the Company is not aware of a material impact from the novel coronavirus disease (“COVID-19”) pandemic through March 31, 2022, the full extent to which COVID-19 will directly or indirectly impact the Company’s business, results of operations and financial condition, including manufacturing, clinical trials and research and development costs, depends on future developments that are uncertain at this time. ​

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2022
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies ​ Basis of Presentation ​ The condensed consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States (“GAAP”) for interim financial information. Certain information and footnotes normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The financial statements include the consolidated accounts of the Company and its wholly-owned subsidiary, Onconova Europe GmbH. All significant intercompany transactions have been eliminated. ​ Unaudited Interim Financial Information ​ The accompanying condensed consolidated balance sheet as of March 31, 2022, the condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2022 and 2021, the consolidated statements of stockholders’ equity (deficit) for the three months ended March 31, 2022 and 2021 and the condensed consolidated statements of cash flows for the three months ended March 31, 2022 and 2021 are unaudited. The interim unaudited condensed consolidated financial statements have been prepared on the same basis as the annual audited consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of March 31, 2022, the results of its operations for the three months ended March 31, 2022 and 2021, and its cash flows for the three months ended March 31, 2022 and 2021. The financial data and other information disclosed in these notes related to the three months ended March 31, 2022 and 2021 are unaudited. The results for the three months ended March 31, 2022 are not necessarily indicative of results to be expected for the year ending December 31, 2022, any other interim periods, or any future year or period. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto for the year ended December 31, 2021 included in the Company’s annual report on Form 10-K filed with the SEC on March 21, 2022. ​ All common stock, equity, share and per share amounts in the financial statements and notes have been retroactively adjusted to reflect a one-for-fifteen reverse stock split which was effective May 20, 2021. ​ Segment Information ​ Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one segment, which is the identification and development of oncology therapeutics. ​ Significant Accounting Policies ​ The Company’s significant accounting policies are disclosed in the audited consolidated financial statements for the year ended December 31, 2021 included in the Company’s annual report on Form 10-K filed with the SEC on March 21, 2022. Since the date of such financial statements, there have been no changes to the Company’s significant accounting policies. ​ Fair Value Measurements ​ The carrying amounts reported in the accompanying consolidated financial statements for cash and cash equivalents, accounts payable, and accrued liabilities approximate their respective fair values because of the short-term nature of these accounts. The fair value of the warrant liability is discussed in Note 7, “Fair Value Measurements.” ​ Recent Accounting Pronouncements ​ In June 2016, the FASB issued new guidance on the accounting for credit losses on financial instruments. The guidance was amended in November 2019. The new guidance introduces an expected loss model for estimating credit losses, replacing the incurred loss model. The new guidance also changes the impairment model for available-for-sale debt securities, requiring the use of an allowance to record estimated credit losses (and subsequent recoveries). The guidance is effective for the Company in fiscal years beginning after December 15, 2022, and interim periods within those years, with early adoption permitted. The guidance is not expected to have a material effect on the Company.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2022
Revenue.
Revenue	3. Revenue ​ The Company’s revenue during the three months ended March 31, 2022 and 2021 was from its license and collaboration agreement with SymBio. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2022 2021 Symbio ​ ​ ​ ​ ​ ​ ​ Upfront license fee recognition over time ​ $ 56,000 ​ $ 56,000 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deferred revenue is as follows: ​ ​ ​ ​ ​ ​ ​ Symbio ​ Upfront Payment Deferred balance at December 31, 2021 ​ $ 3,469,000 Recognition to revenue ​ ​ (56,000) ​ ​ ​ ​ Deferred balance at March 31, 2022 ​ $ 3,413,000 ​

Net Loss Per Share of Common St

Net Loss Per Share of Common Stock	3 Months Ended
	Mar. 31, 2022
Net Loss Per Share of Common Stock
Net Loss Per Share of Common Stock	4. Net Loss Per Share of Common Stock ​ The following potentially dilutive securities outstanding at March 31, 2022 and 2021 have been excluded from the computation of diluted weighted average shares outstanding, as they would be antidilutive (reflects the number of common shares as if the dilutive securities had been converted to common stock): ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ 2022 2021 Warrants 491,586 512,202 Stock options 871,842 43,026 ​ 1,363,428 555,228 ​

Warrants

Warrants	3 Months Ended
	Mar. 31, 2022
Warrants
Warrants	5. Warrants ​ Common Stock warrants are accounted for in accordance with applicable accounting guidance provided in ASC Topic 815, Derivatives and Hedging - Contracts in Entity’s Own Equity ​ ​ Warrants outstanding and warrant activity (reflects the number of common shares as if the warrants were converted to common stock) for the three months ended March 31, 2022 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance ​ ​ ​ ​ ​ ​ ​ Balance ​ ​ ​ ​ Exercise ​ Expiration ​ December 31, ​ Warrants ​ Warrants ​ Warrants ​ March 31, Description Classification Price Date 2021 Issued Exercised Expired 2022 Non-tradable pre-funded warrants Equity ​ $ 2.25 July 2023 26 — — — 26 Non-tradable warrants ​ Equity ​ $ 24.00 ​ December 2022 ​ 26,189 ​ — ​ — ​ — ​ 26,189 Non-tradable pre-funded warrants ​ Equity ​ $ 2.25 ​ none ​ 3,522 ​ — ​ — ​ — ​ 3,522 Non-tradable warrants ​ Equity ​ $ 24.00 ​ December 2022 ​ 120,407 ​ — ​ — ​ — ​ 120,407 Non-tradable pre-funded warrants ​ Equity ​ $ 2.25 ​ none ​ 4,974 ​ — ​ — ​ — ​ 4,974 Non-tradable warrants ​ Equity ​ $ 30.00 ​ September 2023 ​ 7,306 ​ — ​ — ​ — ​ 7,306 Non-tradable warrants ​ Equity ​ $ 3.00 ​ November 2024 ​ 244,500 ​ — ​ — ​ — ​ 244,500 Non-tradable warrants ​ Equity ​ $ 6.54375 ​ December 2024 ​ 16,953 ​ — ​ — ​ — ​ 16,953 Non-tradable warrants ​ Equity ​ $ 6.75450 ​ December 2024 ​ 46,263 ​ — ​ — ​ — ​ 46,263 Non-tradable warrants ​ Equity ​ $ 6.77850 ​ December 2023 ​ 29,968 ​ — ​ — ​ — ​ 29,968 ​ ​ ​ ​ ​ ​ ​ ​ ​ 500,108 ​ — ​ — ​ — ​ 500,108 ​

Balance Sheet Detail

Balance Sheet Detail	3 Months Ended
	Mar. 31, 2022
Balance Sheet Detail
Balance Sheet Detail	6. Balance Sheet Detail ​ Prepaid expenses and other current assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ ​ 2022 2021 ​ Research and development ​ $ 18,000 ​ $ 15,000 ​ Manufacturing ​ 4,000 ​ 29,000 ​ Insurance ​ 255,000 ​ 253,000 ​ Other ​ 306,000 ​ 35,000 ​ ​ ​ $ 583,000 ​ $ 332,000 ​ ​ Property and equipment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2022 2021 Property and equipment ​ $ 70,000 ​ $ 70,000 Accumulated depreciation ​ (35,000) ​ (32,000) ​ ​ $ 35,000 ​ $ 38,000 ​ Accrued expenses and other current liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ ​ 2022 2021 ​ Research and development ​ $ 1,765,000 ​ $ 1,759,000 ​ Employee compensation ​ 727,000 ​ 1,217,000 ​ Professional fees ​ ​ 108,000 ​ ​ 156,000 ​ ​ ​ $ 2,600,000 ​ $ 3,132,000 ​ ​

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2022
Fair Value Measurements
Fair Value Measurements	7. Fair Value Measurements ​ At both March 31, 2022 and December 31, 2021, the Company had no financial assets and liabilities measured at fair value on a recurring basis. ​ Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. ​ The Company utilizes a valuation hierarchy for disclosure of the inputs to the valuations used to measure fair value. This hierarchy prioritizes the inputs into three broad levels as follows. Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable for the asset or liability, either directly or indirectly through market corroboration, for substantially the full term of the financial instrument. Level 3 inputs are unobservable inputs based on the Company’s own assumptions used to measure assets and liabilities at fair value. A financial asset or liability’s classification within the hierarchy is determined based on the lowest level input that is significant to the fair value measurement. ​ During 2021, the Company had tradable warrants and non-tradable warrants that were classified as liabilities and measured at fair value on a recurring basis. The tradable warrants were listed on the Nasdaq Capital Market. The Company determined that an active and orderly market for the tradable warrants developed and that the Nasdaq Capital Market price was the best indicator of fair value of the warrant liability. The quoted market price was used to determine the fair value. The fair value of the non-tradable warrants was estimated using the Black-Scholes pricing model. All of these tradable and non-tradable warrants expired in July 2021. During the three months ended March 31, 2021, there was an increase in the fair value of the warrant liability of $636,000.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2022
Stock-Based Compensation
Stock-Based Compensation	8. Stock-Based Compensation ​ The 2018 Omnibus Incentive Compensation Plan (the “2018 Plan”) was unanimously approved by the Company’s Board of Directors on May 24, 2018 and was approved by the Company’s stockholders on June 27, 2018. ​ Under the 2018 Plan, the Company may grant incentive stock options, non-qualified stock options, stock awards, stock units, stock appreciation rights and other stock-based awards to employees, non-employee directors and consultants, and advisors. The maximum aggregate number of shares of the Company’s common stock that may be issued under the 2018 Plan is 26,823. ​ The 2018 Plan was amended and restated following unanimous approval of the Company’s Board of Directors on April 24, 2019 and was approved by the Company’s shareholders on June 17, 2019. The amended 2018 Plan (the “Amended Plan”) allowed for an additional 39,300 shares of the Company’s common stock that may be issued under the Amended Plan with respect to awards made on and after June 17, 2019. ​ The 2021 Incentive Compensation Plan (the “2021 Plan”) was unanimously approved by the Company’s shareholders on July 30, 2021. Upon stockholders’ approval of the 2021 Plan, no further awards will be made under the amended 2018 Plan. Under the 2021 Plan, the Company may grant incentive stock options, non-qualified stock options, stock awards, stock units, stock appreciation rights and other stock-based awards to employees, non-employee directors and consultants, and advisors. The maximum aggregate number of shares of the Company’s common stock that may be issued under the 2021 Plan is 1,300,000. At March 31, 2022, there were 230,215 shares available for future issuance. ​ Stock-based compensation expense includes stock options granted to employees and non-employees and has been reported in the Company’s statements of operations and comprehensive loss in either research and development expenses or general and administrative expenses depending on the function performed by the optionee. No net tax benefits related to the stock-based compensation costs have been recognized since the Company’s inception. The Company recognized stock-based compensation expense related to stock options and restricted stock units as follows for the three months ended March 31, 2022 and 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2022 2021 General and administrative ​ $ 187,000 ​ $ 56,000 ​ Research and development ​ ​ 109,000 ​ ​ 9,000 ​ ​ ​ $ 296,000 ​ $ 65,000 ​ ​ A summary of stock option activity for the three months ended March 31, 2022 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ Average ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Remaining ​ Aggregate ​ ​ ​ ​ Number ​ Exercise ​ Contractual ​ Intrinsic ​ ​ of Shares Price Term (in years) Value Balance, December 31, 2021 ​ ​ 452,999 ​ $ 20.71 9.42 ​ $ — Authorized ​ ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ Granted ​ ​ 418,125 ​ $ 1.82 ​ 9.86 ​ — Exercised ​ ​ — ​ $ — ​ — ​ $ — Forfeitures/adjustments ​ ​ 718 ​ $ 13,792.50 ​ — ​ ​ Balance, March 31, 2022 ​ ​ 871,842 ​ $ 11.64 9.50 ​ $ 8,362.50 Exercisable at March 31, 2022 ​ ​ 32,874 ​ $ 218.85 7.25 ​ $ — ​ The Company accounts for all stock-based payments made to employees, non-employees and directors using an option pricing model for estimating fair value. Accordingly, stock-based compensation expense is measured based on the estimated fair value of the awards on the date of grant, net of forfeitures. Compensation expense is recognized for the portion that is ultimately expected to vest over the period during which the recipient renders the required services to the Company using the straight-line single option method. ​ The Company uses the Black-Scholes option-pricing model to estimate the fair value of stock options at the grant date. The Black-Scholes model requires the Company to make certain estimates and assumptions, assumptions related to the expected price volatility of the Common Stock, the period during which the options will be outstanding, the rate of return on risk-free investments and the expected dividend yield for the Company’s stock. ​ As of March 31, 2022, there was $1,986,000 of unrecognized compensation expense related to the unvested stock options which is expected to be recognized over a weighted-average period of approximately 2.38 years. ​ The weighted-average assumptions underlying the Black-Scholes calculation of grant date fair value of stock options include the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, ​ ​ ​ 2022 2021 Risk-free interest rate ​ 1.80 % ​ 0.62 % Expected volatility ​ 121.76 % ​ 124.67 % Expected term ​ 5.85 years ​ 6.25 years Expected dividend yield ​ 0 % ​ 0 % Weighted average grant date fair value ​ $ 1.58 ​ $ 3.75 ​ ​ ​ The weighted-average valuation assumptions were determined as follows: ​ ● Risk-free interest rate: The Company based the risk-free interest rate on the interest rate payable on U.S. Treasury securities in effect at the time of grant for a period that is commensurate with the assumed expected option term. ​ ● Expected term of options: Due to its lack of sufficient historical data, the Company estimates the expected life of its employee stock options using the “simplified” method, as prescribed in Staff Accounting Bulletin (SAB) No. 107, whereby the expected life equals the arithmetic average of the vesting term and the original contractual term of the option. ​ ● Expected stock price volatility: Expected volatility is based on the historical volatility of the Company’s Common Stock. ​ ● Expected annual dividend yield: The Company has never paid, and does not expect to pay, dividends in the foreseeable future. Accordingly, the Company assumed an expected dividend yield of 0.0% . ​ On August 2, 2021, the compensation committee of the board of directors approved restricted stock unit grants to the Company’s employees (“2021 RSU”). An aggregate of 104,700 service-based RSUs were issued at a grant date fair value of $5.19 . The 2021 RSU awards will be settled in stock, vest on the third anniversary of the date of grant. The 2021 RSU awards were granted under the 2021 Plan. There were no vesting events, expirations, forfeitures, or cancelations of the 2021 RSUs during the period. On February 7, 2022, the compensation committee of the board of directors approved restricted stock unit grants to the Companies employees (“2022 RSU”). An aggregate of . The 2022 RSU awards will be settled in stock, vest ​ ​ G rants of PSUs and SARs ​ On July 9, 2020, the compensation committee of the board of directors and the board approved a cash bonus program of cash-settled stock appreciation right (“2020 SAR”) awards and cash-settled performance stock unit (“2020 PSU”) awards to the Company’s employees. An aggregate of 2020 SAR awards with respect to 256,713 shares of common stock and 2020 PSU awards with respect to 124,220 shares of common stock were granted to the Company’s employees. The 2020 SAR awards will be settled in cash, vest 33% on the first anniversary of the date of grant, and the remaining 67% monthly over the next 24 months, have a per-share base amount of $8.40, which was the closing sales price of a share of the Company’s common stock on the grant date, and are in all cases subject to the terms and conditions of the Company’s form of SAR award agreement. The 2020 SAR awards are cash-settled and were granted outside of the 2018 Plan and the 2021 Plan. ​ The 2020 PSU awards vest 50% upon the submission of a new drug application (“NDA”) to the U.S. FDA for rigosertib in higher-risk myelodysplastic syndromes (“HR-MDS”) and 50% upon U.S. FDA approval of rigosertib for HR-MDS. The 2020 PSU awards have a maximum value of per share. The maximum price per share is the per-share value based on the Company’s market capitalization at shares on July 9, 2020. In all cases, the 2020 PSU awards are subject to the terms and conditions of the Company’s form of PSU award agreement. The 2020 PSU awards are cash-settled and were granted outside of the 2018 Plan and the 2021 Plan. ​ In addition, on July 9, 2020, based on the recommendation of the compensation committee, the board approved a change in the non-employee director compensation policy that would provide for an annual SAR award (“2020 Director SAR”) with respect to 8,333 shares of common stock for each of the Company’s non-employee directors. No other changes to the non-employee director compensation policy were approved and, on July 9, 2020, the Board approved the initial 8,333 2020 Director SAR award to each of the non-employee directors for an aggregate total of 58,333 2020 Directors SAR awards granted. The 2020 Director SAR awards vest on the first anniversary of grant subject to the director’s continued service and will be settled in cash, have a per-share base amount of ​ Each SAR subject to a 2020 SAR award represents the right to a cash payment equal to the excess, if any, of (i) the fair market value of each underlying share of the Company’s common stock, determined on the date of exercise of the SAR minus (ii) the base amount. Pursuant to the terms of the SAR awards, in no event may the cash payment for each SAR exceed $13.20, which is the maximum price per share of $21.60, minus the base amount of $8.40, subject to adjustment in accordance with the terms of the Stock Appreciation Right Award Agreement. The maximum price per share is the per-share value based on the Company’s market capitalization at $250 million and the Company’s outstanding shares of common stock, which was 11,611,829 shares on July 9, 2020. ​ On February 17, 2021, the compensation committee of the board of directors and the board approved a cash bonus program of cash-settled stock appreciation right (“2021 SAR”) awards and cash-settled performance stock unit (“2021 PSU”) awards to the Company’s employees. An aggregate of 2021 SAR awards with respect to 100,000 shares of common stock and 2021 PSU awards with respect to 100,000 shares of common stock were granted to the Company’s employees. The 2021 SAR awards will be settled in cash, vest 33% on the first anniversary of the date of grant, and the remaining 67% monthly over the next 24 months, have a per-share base amount of $22.65, which was the closing sales price of a share of the Company’s common stock on the grant date, and are in all cases subject to the terms and conditions of the Company’s form of SAR award agreement. Each SAR subject to a 2021 SAR award represents the right to a cash payment equal to the excess, if any, of (i) the fair market value of each underlying share of the Company’s common stock, determined on the date of exercise of the 2021 SAR minus (ii) the base amount. Pursuant to the terms of the 2021 SAR awards, in no event may the cash payment for each SAR exceed $15.45, which is the maximum price per share of $38.10, minus the base amount of $22.65 , subject to adjustment in accordance with the terms of the Stock Appreciation Right Award Agreement. The maximum price per share is the per-share value based on the Company’s market capitalization at ​ The 2021 PSU awards vest 20% upon the initiation of a new clinical program with an in-licensed compound, 20% for reaching the recommended Phase 2 dose for any compound, 20% for the first patient enrolled in the expansion cohort of the Phase 1 ON123300 clinical trial, 20% for the first patient enrolled in a registrational study for any compound, and 20% for the topline data of a registrational study for any compound. The 2021 PSU awards have a maximum value of per share. The maximum price per share is the per-share value based on the Company’s approximate market capitalization at shares on February 17, 2021. In all cases, the 2021 PSU awards are subject to the terms and conditions of the Company’s form of PSU award agreement. The 2021 PSU awards are cash-settled and were granted outside of the 2018 Plan and the 2021 Plan. ​ The fair value of the 2021 SARs granted has been estimated using the Black-Scholes option-pricing model with the following weighted-average assumptions: ​ ​ ​ ​ ​ ​ ​ As of March 31, 2022 ​ ​ ​ Risk-free interest rate ​ 2.42 % Expected volatility ​ 132.18 % Expected term ​ 5.39 years Expected dividend yield ​ 0 % ​ During the three months ended March 31, 2022, the Company recognized $16,000 of reversals of compensation expense related to the SARs and PSUs. As of March 31, 2022, the SARs and PSUs liability was $70,000 and is included in accrued expenses. As of March 31, 2022, there was

Research Agreements

Research Agreements	3 Months Ended
	Mar. 31, 2022
Research Agreements
Research Agreements	9. Research Agreements ​ The Company has entered into various licensing and right-to-sublicense agreements with educational institutions for the exclusive use of patents and patent applications, as well as any patents that may develop from research being conducted by such educational institutions in the field of anticancer therapy, genes and proteins. Results from this research have been licensed to the Company pursuant to these agreements. Under one of these agreements with Temple University (“Temple”), the Company is required to make annual maintenance payments to Temple and royalty payments based upon a percentage of sales generated from any products covered by the licensed patents, with minimum specified royalty payments. As no sales had been generated through March 31, 2022 under the licensed patents, the Company has not incurred any royalty expenses related to this agreement. In addition, the Company is required to pay Temple a percentage of any sublicensing fees received by the Company.

Securities Registrations and Sa

Securities Registrations and Sales Agreements	3 Months Ended
	Mar. 31, 2022
Securities Registrations and Sales Agreements
Securities Registrations and Sales Agreements	10. Securities Registrations and Sales Agreements ​ January 2021 Offering ​ On January 7, 2021, the Company entered into a purchase agreement with certain institutional and accredited investors for the sale of an aggregate of 1,303,408 shares of the Company’s common stock, at a purchase price of $6.675 per share. ​ Under the purchase agreement, subject to certain exceptions, the Company is prohibited from effecting or entering into an agreement to effect any “variable rate transactions” as defined in the purchase agreement for a period of five years following the closing of the offering. ​ In connection with the offering, pursuant to the purchase agreement we reimbursed Lincoln Park Capital Fund, LLC, as the lead investor (“Lincoln Park”), an aggregate of $100,000 for expenses incurred in connection with the offering, including any due diligence expenses and legal fees. Furthermore, pursuant to the purchase agreement, we have granted Lincoln Park certain rights to participate at fair value with other investors in up to 50% of the amount of any future offerings of common stock or securities exercisable for or convertible into common stock that the Company seeks to complete within one year after the closing of the offering, other than a firm commitment public offering. ​ The net proceeds to the Company from the offering, after deducting Lincoln Park’s expenses and other estimated offering expenses payable by the Company were approximately $8.5 million. ​ The shares sold in the offering were offered and sold by the Company directly to the investors, without a placement agent, underwriter, broker or dealer, pursuant to an effective shelf registration statement on Form S-3 (File No. 333-237844) declared effective by the SEC on May 18, 2020, and the base prospectus contained therein. The offering closed on January 11, 2021. ​ February 2021 Offering ​ On February 10, 2021, the Company entered into an underwriting agreement with Guggenheim Securities, LLC, as representative of several underwriters, for the public offering of 1,666,667 shares of the Company’s common stock, at a public offering price of $15.00 per share. Under the terms of the underwriting agreement, the Company granted the underwriters an option, exercisable for 30 days, to purchase up to an additional 250,000 shares of common stock at the same price. The option was exercised prior to closing. ​ In connection with the offering, the Company paid the underwriters a cash fee equal to 6% of the gross proceeds in the offering and $100,000 in legal fees and expenses. ​ The net proceeds to the Company from the offering, including exercise of the underwriters’ option, were approximately $26.7 million, after deducting fees and estimated offering expenses payable by the Company. ​ The offering was made pursuant to a registration statement (No. 333-237844) on Form S-3, which was initially filed by the Company with the SEC on April 24, 2020, amended on Form S-3/A that was filed with the SEC on May 15, 2020, and was declared effective by the SEC on May 18, 2020. The offering closed on February 16, 2021. ​ August 2021 Equity Distribution Agreement ​ On August 20, 2021, the Company entered into an Equity Distribution Agreement (the “Equity Distribution Agreement”) with Piper Sandler & Co. (“Piper Sandler”) under which the Company may offer and sell, from time to time at its sole discretion, shares of the Company’s common stock, with aggregate gross sales proceeds of up to $25.0 million through an “at the market” equity offering program under which Piper Sandler is the sales agent. ​ Under the Equity Distribution Agreement, the Company has the right to set the parameters for the sale of shares, including the number of shares to be issued, the time period during which sales are requested to be made, limitations on the number of shares that may be sold in any one trading day and any minimum price below which sales may not be made. Subject to the terms and conditions of the Equity Distribution Agreement, Piper Sandler may sell the shares by methods deemed to be an “at the market” offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made through The Nasdaq Capital Market or any other trading market for our common stock. The Equity Distribution Agreement provides that Piper Sandler is entitled to compensation for its services equal to 3.0% of the gross proceeds of any shares of common stock sold through Piper Sandler under the Equity Distribution Agreement. The Company has no obligation to sell any shares under the Equity Distribution Agreement, and may at any time suspend solicitation and offers under the Equity Distribution Agreement. Through March 31, 2022, the Company sold 109,523 shares under the agreement at a weighted average price of $5.32 per share. Net proceeds after commissions and offering expenses were approximately $0.5 million. There were no shares sold by the Company under the agreement during the three months ended March 31, 2022. ​ The shares are issued pursuant to the Company’s shelf registration statement on Form S-3 (File No. 333-237844). The Company filed a prospectus supplement, dated August 20, 2021 with the Securities and Exchange Commission in connection with the offer and sale of the shares pursuant to the Equity Distribution Agreement. ​ September 2021 Offering ​ On September 23, 2021, the Company entered into an underwriting agreement with Guggenheim Securities, LLC, as representative of several underwriters, for the public offering of 5,000,000 shares of the Company’s common stock, at a public offering price of $4.20 per share. Under the terms of the underwriting agreement, the Company granted the underwriters an option, exercisable for 30 days, to purchase up to an additional 750,000 shares of common stock at the same price. The option was not exercised. ​ In connection with the offering, the Company paid the underwriters a cash fee equal to 6% of the gross proceeds in the offering and $100,000 in legal fees and expenses. ​ The net proceeds to the Company from the offering, including exercise of the underwriters’ option, were approximately $19.5 million, after deducting fees and estimated offering expenses payable by the Company. ​ The offering was made pursuant to a registration statement (No. 333-237844) on Form S-3, which was initially filed by the Company with the SEC on April 24, 2020, amended on Form S-3/A that was filed with the SEC on May 15, 2020, and was declared effective by the SEC on May 18, 2020. The offering closed on September 28, 2021. ​

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2022
Summary of Significant Accounting Policies
Basis of Presentation	Basis of Presentation ​ The condensed consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States (“GAAP”) for interim financial information. Certain information and footnotes normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The financial statements include the consolidated accounts of the Company and its wholly-owned subsidiary, Onconova Europe GmbH. All significant intercompany transactions have been eliminated.
Unaudited Interim Financial Information	Unaudited Interim Financial Information ​ The accompanying condensed consolidated balance sheet as of March 31, 2022, the condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2022 and 2021, the consolidated statements of stockholders’ equity (deficit) for the three months ended March 31, 2022 and 2021 and the condensed consolidated statements of cash flows for the three months ended March 31, 2022 and 2021 are unaudited. The interim unaudited condensed consolidated financial statements have been prepared on the same basis as the annual audited consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of March 31, 2022, the results of its operations for the three months ended March 31, 2022 and 2021, and its cash flows for the three months ended March 31, 2022 and 2021. The financial data and other information disclosed in these notes related to the three months ended March 31, 2022 and 2021 are unaudited. The results for the three months ended March 31, 2022 are not necessarily indicative of results to be expected for the year ending December 31, 2022, any other interim periods, or any future year or period. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto for the year ended December 31, 2021 included in the Company’s annual report on Form 10-K filed with the SEC on March 21, 2022. ​ All common stock, equity, share and per share amounts in the financial statements and notes have been retroactively adjusted to reflect a one-for-fifteen reverse stock split which was effective May 20, 2021.
Segment Information	Segment Information ​ Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one segment, which is the identification and development of oncology therapeutics.
Significant Accounting Policies	Significant Accounting Policies ​ The Company’s significant accounting policies are disclosed in the audited consolidated financial statements for the year ended December 31, 2021 included in the Company’s annual report on Form 10-K filed with the SEC on March 21, 2022. Since the date of such financial statements, there have been no changes to the Company’s significant accounting policies.
Fair Value Measurements	Fair Value Measurements ​ The carrying amounts reported in the accompanying consolidated financial statements for cash and cash equivalents, accounts payable, and accrued liabilities approximate their respective fair values because of the short-term nature of these accounts. The fair value of the warrant liability is discussed in Note 7, “Fair Value Measurements.” ​
Recent Accounting Pronouncements	Recent Accounting Pronouncements ​ In June 2016, the FASB issued new guidance on the accounting for credit losses on financial instruments. The guidance was amended in November 2019. The new guidance introduces an expected loss model for estimating credit losses, replacing the incurred loss model. The new guidance also changes the impairment model for available-for-sale debt securities, requiring the use of an allowance to record estimated credit losses (and subsequent recoveries). The guidance is effective for the Company in fiscal years beginning after December 15, 2022, and interim periods within those years, with early adoption permitted. The guidance is not expected to have a material effect on the Company.

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Mar. 31, 2022
Revenue.
Schedule of recognized revenue under license and collaboration agreements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2022 2021 Symbio ​ ​ ​ ​ ​ ​ ​ Upfront license fee recognition over time ​ $ 56,000 ​ $ 56,000 ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of deferred revenue	​ ​ ​ ​ ​ ​ ​ Symbio ​ Upfront Payment Deferred balance at December 31, 2021 ​ $ 3,469,000 Recognition to revenue ​ ​ (56,000) ​ ​ ​ ​ Deferred balance at March 31, 2022 ​ $ 3,413,000

Net Loss Per Share of Common _2

Net Loss Per Share of Common Stock (Tables)	3 Months Ended
	Mar. 31, 2022
Net Loss Per Share of Common Stock
Schedule of antidilutive securities which have been excluded from the computation of diluted weighted average shares outstanding	​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ 2022 2021 Warrants 491,586 512,202 Stock options 871,842 43,026 ​ 1,363,428 555,228

Warrants (Tables)

Warrants (Tables)	3 Months Ended
	Mar. 31, 2022
Warrants
Schedule of warrants outstanding and warrant activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance ​ ​ ​ ​ ​ ​ ​ Balance ​ ​ ​ ​ Exercise ​ Expiration ​ December 31, ​ Warrants ​ Warrants ​ Warrants ​ March 31, Description Classification Price Date 2021 Issued Exercised Expired 2022 Non-tradable pre-funded warrants Equity ​ $ 2.25 July 2023 26 — — — 26 Non-tradable warrants ​ Equity ​ $ 24.00 ​ December 2022 ​ 26,189 ​ — ​ — ​ — ​ 26,189 Non-tradable pre-funded warrants ​ Equity ​ $ 2.25 ​ none ​ 3,522 ​ — ​ — ​ — ​ 3,522 Non-tradable warrants ​ Equity ​ $ 24.00 ​ December 2022 ​ 120,407 ​ — ​ — ​ — ​ 120,407 Non-tradable pre-funded warrants ​ Equity ​ $ 2.25 ​ none ​ 4,974 ​ — ​ — ​ — ​ 4,974 Non-tradable warrants ​ Equity ​ $ 30.00 ​ September 2023 ​ 7,306 ​ — ​ — ​ — ​ 7,306 Non-tradable warrants ​ Equity ​ $ 3.00 ​ November 2024 ​ 244,500 ​ — ​ — ​ — ​ 244,500 Non-tradable warrants ​ Equity ​ $ 6.54375 ​ December 2024 ​ 16,953 ​ — ​ — ​ — ​ 16,953 Non-tradable warrants ​ Equity ​ $ 6.75450 ​ December 2024 ​ 46,263 ​ — ​ — ​ — ​ 46,263 Non-tradable warrants ​ Equity ​ $ 6.77850 ​ December 2023 ​ 29,968 ​ — ​ — ​ — ​ 29,968 ​ ​ ​ ​ ​ ​ ​ ​ ​ 500,108 ​ — ​ — ​ — ​ 500,108

Balance Sheet Detail (Tables)

Balance Sheet Detail (Tables)	3 Months Ended
	Mar. 31, 2022
Balance Sheet Detail
Schedule of prepaid expenses and other current assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ ​ 2022 2021 ​ Research and development ​ $ 18,000 ​ $ 15,000 ​ Manufacturing ​ 4,000 ​ 29,000 ​ Insurance ​ 255,000 ​ 253,000 ​ Other ​ 306,000 ​ 35,000 ​ ​ ​ $ 583,000 ​ $ 332,000 ​
Schedule of property and equipment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2022 2021 Property and equipment ​ $ 70,000 ​ $ 70,000 Accumulated depreciation ​ (35,000) ​ (32,000) ​ ​ $ 35,000 ​ $ 38,000
Schedule of accrued expenses and other current liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ ​ 2022 2021 ​ Research and development ​ $ 1,765,000 ​ $ 1,759,000 ​ Employee compensation ​ 727,000 ​ 1,217,000 ​ Professional fees ​ ​ 108,000 ​ ​ 156,000 ​ ​ ​ $ 2,600,000 ​ $ 3,132,000 ​

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2022
Stock-based compensation
Schedule of stock-based compensation expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2022 2021 General and administrative ​ $ 187,000 ​ $ 56,000 ​ Research and development ​ ​ 109,000 ​ ​ 9,000 ​ ​ ​ $ 296,000 ​ $ 65,000 ​
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ Average ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Remaining ​ Aggregate ​ ​ ​ ​ Number ​ Exercise ​ Contractual ​ Intrinsic ​ ​ of Shares Price Term (in years) Value Balance, December 31, 2021 ​ ​ 452,999 ​ $ 20.71 9.42 ​ $ — Authorized ​ ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ Granted ​ ​ 418,125 ​ $ 1.82 ​ 9.86 ​ — Exercised ​ ​ — ​ $ — ​ — ​ $ — Forfeitures/adjustments ​ ​ 718 ​ $ 13,792.50 ​ — ​ ​ Balance, March 31, 2022 ​ ​ 871,842 ​ $ 11.64 9.50 ​ $ 8,362.50 Exercisable at March 31, 2022 ​ ​ 32,874 ​ $ 218.85 7.25 ​ $ —
Schedule of weighted-average assumptions used for estimating the fair value of the stock compensation granted	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, ​ ​ ​ 2022 2021 Risk-free interest rate ​ 1.80 % ​ 0.62 % Expected volatility ​ 121.76 % ​ 124.67 % Expected term ​ 5.85 years ​ 6.25 years Expected dividend yield ​ 0 % ​ 0 % Weighted average grant date fair value ​ $ 1.58 ​ $ 3.75 ​ ​
SAR awards
Stock-based compensation
Schedule of weighted-average assumptions used for estimating the fair value of the stock compensation granted	​ ​ ​ ​ ​ ​ ​ As of March 31, 2022 ​ ​ ​ Risk-free interest rate ​ 2.42 % Expected volatility ​ 132.18 % Expected term ​ 5.39 years Expected dividend yield ​ 0 %

Nature of Business (Details)

Nature of Business (Details)	Aug. 20, 2021USD ($)	May 20, 2021$ / sharesshares	Mar. 31, 2022USD ($)Program$ / sharesshares	Mar. 31, 2021USD ($)	Mar. 31, 2022USD ($)Program$ / sharesshares	Dec. 31, 2021USD ($)$ / sharesshares	May 19, 2021shares	Dec. 31, 2020USD ($)
Liquidity
Number of clinical programs (in programs) | Program			2		2
Reverse stock split ratio		0.067
Common stock, par value (in dollars per share) | $ / shares		$ 0.01	$ 0.01		$ 0.01	$ 0.01
Common stock authorized (in shares) | shares		125,000,000	125,000,000		125,000,000	125,000,000	250,000,000
Net loss			$ (4,122,000)	$ (4,715,000)
Accumulated deficit			448,841,000		$ 448,841,000	$ 444,719,000
Cash and cash equivalents			$ 50,767,000	48,005,000	50,767,000	$ 55,070,000		$ 19,025,000
Proceeds from issuance of common stock				$ 35,147,000
Piper Sandler & Co
Liquidity
Proceeds from issuance of common stock	$ 25,000,000				$ 500,000
Issuance of common stock, net (in shares) | shares			0		109,523

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) - segment	May 20, 2021	Mar. 31, 2022
Summary of Significant Accounting Policies
Number of Operating Segments		1
Reverse stock split	one-for-fifteen

Revenue (Details)

Revenue (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Revenue
Revenue	$ 56,000	$ 56,000
Deferred revenue
Balance at the beginning of the period	226,000
Balance at the end of the period	226,000
SymBio
Deferred revenue
Balance at the beginning of the period	3,469,000
Recognition to revenue	(56,000)
Balance at the end of the period	3,413,000
License and collaboration agreements | SymBio
Revenue
Revenue	$ 56,000	$ 56,000

Net Loss Per Share of Common _3

Net Loss Per Share of Common Stock (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Potentially dilutive securities outstanding excluded from the computation of diluted weighted average shares as they would be antidilutive
Potentially dilutive securities outstanding excluded from the computation of diluted weighted average shares	1,363,428	555,228
Warrants.
Potentially dilutive securities outstanding excluded from the computation of diluted weighted average shares as they would be antidilutive
Potentially dilutive securities outstanding excluded from the computation of diluted weighted average shares	491,586	512,202
Stock options
Potentially dilutive securities outstanding excluded from the computation of diluted weighted average shares as they would be antidilutive
Potentially dilutive securities outstanding excluded from the computation of diluted weighted average shares	871,842	43,026

Warrants (Details)

Warrants (Details) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Warrants outstanding and warrant activity
Warrants outstanding	500,108	500,108
Warrant exercise price range one [member]
Warrants
Warrant exercise price (in dollars per share)	$ 2.25
Warrants outstanding and warrant activity
Warrants outstanding	26	26
Warrant exercise price range two [member]
Warrants
Warrant exercise price (in dollars per share)	$ 24
Warrants outstanding and warrant activity
Warrants outstanding	26,189	26,189
Warrant exercise price range three [member]
Warrants
Warrant exercise price (in dollars per share)	$ 2.25
Warrants outstanding and warrant activity
Warrants outstanding	3,522	3,522
Warrant exercise price range four [member]
Warrants
Warrant exercise price (in dollars per share)	$ 24
Warrants outstanding and warrant activity
Warrants outstanding	120,407	120,407
Warrant exercise price range five [member]
Warrants
Warrant exercise price (in dollars per share)	$ 2.25
Warrants outstanding and warrant activity
Warrants outstanding	4,974	4,974
Warrant exercise price range six [member]
Warrants
Warrant exercise price (in dollars per share)	$ 30
Warrants outstanding and warrant activity
Warrants outstanding	7,306	7,306
Warrant exercise price range seven [member]
Warrants
Warrant exercise price (in dollars per share)	$ 3
Warrants outstanding and warrant activity
Warrants outstanding	244,500	244,500
Warrant exercise price range eight [member]
Warrants
Warrant exercise price (in dollars per share)	$ 6.54375
Warrants outstanding and warrant activity
Warrants outstanding	16,953	16,953
Warrant exercise price range nine [member]
Warrants
Warrant exercise price (in dollars per share)	$ 6.75450
Warrants outstanding and warrant activity
Warrants outstanding	46,263	46,263
Warrant exercise price range ten [member]
Warrants
Warrant exercise price (in dollars per share)	$ 6.77850
Warrants outstanding and warrant activity
Warrants outstanding	29,968	29,968

Balance Sheet Detail - Prepaid

Balance Sheet Detail - Prepaid Expenses and Other Current Assets (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Prepaid expenses and other current assets:
Research and development	$ 18,000	$ 15,000
Manufacturing	4,000	29,000
Insurance	255,000	253,000
Other	306,000	35,000
Prepaid expenses and other current assets	$ 583,000	$ 332,000

Balance Sheet Detail - Property

Balance Sheet Detail - Property and Equipment (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Property and Equipment
Property and equipment	$ 70,000	$ 70,000
Accumulated depreciation	(35,000)	(32,000)
Property and equipment, net	$ 35,000	$ 38,000

Balance Sheet Detail - Accrued

Balance Sheet Detail - Accrued Expenses and Other Current Liabilities (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Balance Sheet Detail
Research and development	$ 1,765,000	$ 1,759,000
Employee compensation	727,000	1,217,000
Professional fees	108,000	156,000
Accrued expenses and other current liabilities	$ 2,600,000	$ 3,132,000

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Hierarchy Table (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Liabilities measured at fair value
Warrant liability			$ 636,000
Recurring basis
Liabilities measured at fair value
Financial liabilities	$ 0	$ 0

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($) $ in Millions	Feb. 17, 2021	Jul. 09, 2020	Jun. 17, 2019	Mar. 31, 2022
Stock-Based Compensation
Market Capitalization	$ 600	$ 250
2018 Plan
Stock-Based Compensation
Shares authorized (in shares)				26,823
Additional shares authorized (in shares)			39,300
2021 Incentive Plan
Stock-Based Compensation
Shares authorized (in shares)				1,300,000
Stock options | 2021 Incentive Plan
Stock-Based Compensation
Common Stock available for future issuance (in shares)				230,215

Stock-Based Compensation - Expe

Stock-Based Compensation - Expense (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Stock-Based Compensation
Net tax benefits related to the stock-based compensation costs	$ 0
Compensation expense	296,000	$ 65,000
General and administrative
Stock-Based Compensation
Compensation expense	187,000	56,000
Research and development
Stock-Based Compensation
Compensation expense	$ 109,000	$ 9,000

Stock-Based Compensation - Acti

Stock-Based Compensation - Activity (Details) - Stock options - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Shares Available for Grant
Granted (in shares)	(418,125)
Exercised (in shares)	0
Forfeitures/adjustments (in shares)	(718)
Number of Shares
Balance at the beginning of the period (in shares)	452,999
Granted (in shares)	418,125
Exercised (in shares)	0
Forfeitures/adjustments (in shares)	718
Balance at the end of the period (in shares)	871,842	452,999
Exercisable at the end of the period (in shares)	32,874
Weighted-Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 20.71
Granted (in dollars per share)	1.82
Exercised (in dollars per share)	0
Forfeitures (in dollars per share)	13,792.50
Balance at the end of the period (in dollars per share)	11.64	$ 20.71
Exercisable at the end of the period (in dollars per share)	$ 218.85
Additional Disclosures
Weighted average remaining contractual term	9 years 6 months	9 years 5 months 1 day
Weighted average remaining contractual term of options granted	9 years 10 months 9 days
Weighted average remaining contractual term of options exercisable	7 years 3 months
Aggregate intrinsic value of options outstanding	$ 8,362.50

Stock-Based Compensation - Unre

Stock-Based Compensation - Unrecognized Compensation Expense (Details)	3 Months Ended
	Mar. 31, 2022USD ($)
Stock options
Stock-Based Compensation
Unrecognized compensation expense related to unvested stock options	$ 1,986,000
Weighted-average period for recognizing unrecognized compensation expense related to unvested stock options (in years)	2 years 4 months 17 days
SAR awards
Stock-Based Compensation
Unrecognized compensation expense related to unvested stock options	$ 16,000
2020 SAR
Stock-Based Compensation
Unrecognized compensation expense related to unvested stock options	6,000
2021 SAR
Stock-Based Compensation
Unrecognized compensation expense related to unvested stock options	$ 168,000

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value Assumptions (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Assumptions used
Expected dividend yield (as a percent)	0.00%
SARs liability	$ 70,000
Stock options
Assumptions used
Risk-free interest rate (as a percent)	1.80%	0.62%
Expected volatility (as a percent)	121.76%	124.67%
Expected term (in years)	5 years 10 months 6 days	6 years 3 months
Expected dividend yield (as a percent)	0.00%	0.00%
Weighted average grant date fair value (in dollars per share)	$ 1.58	$ 3.75
2021 SAR
Assumptions used
Risk-free interest rate (as a percent)	2.42%
Expected volatility (as a percent)	132.18%
Expected term	5.39
Expected dividend yield (as a percent)	0.00%

Stock-Based Compensation - Gran

Stock-Based Compensation - Grants of PSUs and SARs (Details) - USD ($)	Feb. 07, 2022	Aug. 02, 2021	Feb. 17, 2021	Jul. 09, 2020	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per share (in dollars per share)				$ 21.60
Common stock outstanding (in shares)				11,611,829	20,895,563		20,895,563
Market capitalization			$ 600,000,000	$ 250,000,000
Compensation expense					$ 296,000	$ 65,000
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock outstanding (in shares)				11,611,829
SAR Award Agreement [member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock outstanding (in shares)			15,767,492
SAR Award Agreement [member] | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per share (in dollars per share)					$ 38.10
SAR Award Agreement [member] | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per share (in dollars per share)					$ 22.65
PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants				124,220
2021 PSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock outstanding (in shares)			15,767,492
Market capitalization			$ 600,000,000
Shares issued					100,000
2021 PSU | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per share (in dollars per share)			$ 38.10
2021 PSU | Initiation of a new clinical program with an in-licensed compound
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)			20.00%
2021 PSU | Reaching the recommended Phase 2 dose for any compound
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)			20.00%
2021 PSU | First patient enrolled in the expansion cohort of the Phase 1 ON123300 clinical trial
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)			20.00%
2021 PSU | First patient enrolled in a registrational study for any compound
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)			20.00%
2021 PSU | Topline data of a registrational study for any compound
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)			20.00%
SAR awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants				256,713
Price per share (in dollars per share)				$ 8.40	$ 15.45
Issue price (in dollars per share)				13.20
Unrecognized compensation expense related to unvested stock options					$ 16,000
SAR awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per share (in dollars per share)				$ 21.60
2020 SAR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to unvested stock options					$ 6,000
2021 SAR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)			67.00%		33.00%
Price per share (in dollars per share)			$ 22.65
Shares issued					100,000
Unrecognized compensation expense related to unvested stock options					$ 168,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants	148,343	104,700
Price per share (in dollars per share)	$ 1.82	$ 5.19
Compensation expense					$ 681,000
Vesting Percentage One | PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)				50.00%
Vesting Percentage One | SAR awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)				33.00%
Vesting Percentage One | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)	33.00%				33.00%
Vesting Percentage Two | PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)				50.00%
Vesting Percentage Two | SAR awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)				67.00%
Vesting Percentage Two | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (Percentage)	34.00%				34.00%
Employee | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense					$ 57,000
Non employee directors | SAR awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grants				58,333
Number of awards issued				8,333

Research Agreements (Details)

Research Agreements (Details)	3 Months Ended
	Mar. 31, 2022USD ($)
License
Research Agreements
Revenue	$ 0

Securities Registrations and _2

Securities Registrations and Sales Agreements (Details) - USD ($)	Sep. 23, 2021	Aug. 20, 2021	Feb. 10, 2021	Jan. 07, 2021	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Jul. 09, 2020
Price per share (in dollars per share)								$ 21.60
Proceeds from issuance of common stock						$ 35,147,000
SAR awards
Price per share (in dollars per share)					$ 15.45		$ 15.45	8.40
Issue price (in dollars per share)								13.20
Lincoln Park Capital Fund, LLC | The Offering
Expense reimbursement				$ 100,000
Percentage rights to participate				50.00%
Threshold period for exercise or conversion of stock				one year
Institutional Investors | The Offering
Issuance of common stock, net (in shares)				1,303,408
Issue price (in dollars per share)				$ 6.675
Proceeds from issuance of common stock				$ 8,500,000
Guggenheim Securities, LLC | The Offering
Issuance of common stock, net (in shares)	5,000,000
Price per share (in dollars per share)	$ 4.20
Underwriters option exercisable term	30 days
Proceeds from issuance of common stock	$ 19,500,000
Cash fee	6.00%
Legal fees and expenses	$ 100,000
Guggenheim Securities, LLC | Over-allotment
Issuance of common stock, net (in shares)			1,666,667
Issue price (in dollars per share)			$ 15
Threshold period for exercise or conversion of stock			30 days
Proceeds from issuance of common stock			$ 26,700,000
Additional shares agreed to issue			250,000
Cash fee			6.00%
Legal fees and expenses			$ 100,000
Piper Sandler & Co
Issuance of common stock, net (in shares)					0		109,523
Issue price (in dollars per share)					$ 5.32		$ 5.32
Proceeds from issuance of common stock		$ 25,000,000					$ 500,000
Percentage of gross proceeds of shares of common stock sold		3.00%
Maximum | SAR awards
Price per share (in dollars per share)								$ 21.60
Maximum | Guggenheim Securities, LLC | Over-allotment
Issuance of common stock, net (in shares)	750,000