Oncternal Therapeutics (ONCT) 10-Q 4 May 23 2023 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2023	Apr. 28, 2023
Cover [Abstract]
Entity Registrant Name	Oncternal Therapeutics, Inc.
Entity Central Index Key	0001260990
Document Type	10-Q
Document Period End Date	Mar. 31, 2023
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1
Trading Symbol	ONCT
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		58,711,451
Entity File Number	000-50549
Entity Tax Identification Number	62-1715807
Entity Address, Address Line One	12230 El Camino Real
Entity Address, Address Line Two	Suite 230
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92130
City Area Code	858
Local Phone Number	434-1113
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, $0.001 par value
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 11,244	$ 37,142
Short-term investments	43,073	26,582
Prepaid and other	3,600	3,566
Total current assets	57,917	67,290
Right-of-use asset	50	87
Other assets	315	1,274
Total assets	58,282	68,651
Current liabilities:
Accounts payable	1,964	2,917
Accrued liabilities	3,474	4,678
Lease liability	50	87
Total current liabilities	5,488	7,682
Deferred compensation	306	0
Commitments and contingencies (Note 4)
Stockholders’ equity:
Preferred stock, $0.001 par value, authorized shares - 5,000 at March 31, 2023 and December 31, 2022; issued and outstanding shares - none	0	0
Common stock, $0.001 par value; authorized shares - 120,000; issued and outstanding shares - 58,711 and 57,464 at March 31, 2023 and December 31, 2022, respectively	59	57
Additional paid-in capital	222,205	219,203
Accumulated comprehensive income	11	9
Accumulated deficit	(169,787)	(158,300)
Total stockholders’ equity	52,488	60,969
Total liabilities and stockholders’ equity	$ 58,282	$ 68,651

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) - $ / shares	Mar. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
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	$ 0.001	$ 0.001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	58,711,000	57,464,000
Common stock, shares outstanding	58,711,000	57,464,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
Grant revenue	$ 203	$ 746
Operating expenses:
Research and development	9,031	6,979
General and administrative	3,315	3,679
Total operating expenses	12,346	10,658
Loss from operations	(12,143)	(9,912)
Interest income	656	8
Net loss	(11,487)	(9,904)
Comprehensive Income:
Unrealized gain on available-for-sale securities, net	2	0
Comprehensive loss	$ (11,485)	$ (9,904)
Net loss per share, basic	$ (0.20)	$ (0.20)
Net loss per share, diluted	$ (0.20)	$ (0.20)
Weighted-average shares outstanding, basic	58,522	49,429
Weighted-average shares outstanding, diluted	58,522	49,429

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities
Net loss	$ (11,487)	$ (9,904)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	1,885	1,978
Amortization of premiums (accretion of discounts) on short-term investments	(441)	0
Non-cash lease expense	37	44
Changes in operating assets and liabilities:
Prepaid and other	925	(553)
Accounts payable	(953)	436
Accrued liabilities	(1,204)	(563)
Deferred compensation	306	0
Change in lease liability	(37)	(44)
Net cash used in operating activities	(10,969)	(8,606)
Cash flows from investing activities
Purchases of available-for-sale securities	(22,048)	0
Maturities of available-for-sale securities	6,000	0
Net cash used in investing activities	(16,048)	0
Cash flows from financing activities
Proceeds from issuance of common stock in public offerings, net	1,224	0
Repurchases of common stock for tax withholding obligations	(105)	0
Net cash provided by financing activities	1,119	0
Net decrease in cash and cash equivalents	(25,898)	(8,606)
Cash and cash equivalents at beginning of period	37,142	90,765
Cash and cash equivalents at end of period	$ 11,244	$ 82,159

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income	Accumulated Deficit
Balance at Dec. 31, 2021	$ 88,120	$ 49	$ 202,201		$ (114,130)
Balance (in shares) at Dec. 31, 2021		49,429
Stock-based compensation	1,978		1,978
Net loss	(9,904)				(9,904)
Balance at Mar. 31, 2022	80,194	$ 49	204,179		(124,034)
Balance (in shares) at Mar. 31, 2022		49,429
Balance at Dec. 31, 2022	$ 60,969	$ 57	219,203	$ 9	(158,300)
Balance (in shares) at Dec. 31, 2022	57,464	57,464
Issuance of common stock upon vesting of restricted stock units (in Shares)		218
Shares repurchased for settlement of minimum statutory tax withholdings (in shares)		(86)
Shares repurchased for settlement of minimum statutory tax withholdings	$ (105)		(105)
Issuance of common stock, net of issuance cost of $287	1,224	$ 2	1,222
Issuance of common stock, net of issuance cost (in shares)		1,115
Unrealized gain on available-for-sale securities	2			2
Stock-based compensation	1,885		1,885
Net loss	(11,487)				(11,487)
Balance at Mar. 31, 2023	$ 52,488	$ 59	$ 222,205	$ 11	$ (169,787)
Balance (in shares) at Mar. 31, 2023	58,711	58,711

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity (Parenthetical) (Unaudited) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Statement of Stockholders' Equity [Abstract]
Common stock, issuance cost	$ 38

Description of Business, Basis

Description of Business, Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business, Basis of Presentation and Summary of Significant Accounting Policies	1. Description of Business, Basis of Presentation and Summary of Significant Accounting Policies Description of Business Oncternal Therapeutics, Inc. (the “Company” or “Oncternal”), formerly known as GTx, Inc., was incorporated in Tennessee in September 1997 and reincorporated in Delaware in 2003 and is based in San Diego, California. The Company is a clinical-stage biopharmaceutical company focused on the development of novel oncology therapies, for the treatment of cancers with critical unmet medical need. The Company’s product candidate pipeline includes ONCT-808, an autologous ROR1 (Receptor-tyrosine kinase-like Orphan Receptor 1) targeting CAR T (chimeric antigen receptor T cells), ONCT-534, a dual-action androgen receptor inhibitor (“DAARI”) for the treatment of castrate-resistant prostate and other androgen receptor-driven cancers, and zilovertamab, a humanized monoclonal antibody that binds to ROR1. Principles of Consolidation The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries, Oncternal Oncology, Inc. and Oncternal, Inc. All intercompany accounts and transactions have been eliminated in the preparation of the condensed consolidated financial statements. Liquidity From inception, the Company has devoted substantially all of its efforts to drug discovery and development and conducting preclinical studies and clinical trials. The Company has a limited operating history and the sales and income potential of the Company’s business and market are unproven. Successful transition to attaining profitable operations is dependent upon achieving a level of revenues adequate to support the Company’s cost structure. As a result of the strategic reprioritization announced in April 2023, the Company expects research and development expenses will decrease in future quarters after the closure of the Phase 3 ZILO-301 Study for the treatment of patients with relapsed or refractory MCL and the Phase 1/2 CIRM-0001 Study for the treatment of mantle cell lymphoma (“MCL”), chronic lymphocytic leukemia ( “CLL”) and marginal zone lymphoma (“MZL”), and the implementation of other cost reductions (see Note 9). The Company will continue to invest in: (i) advancing existing product candidates into later stages of clinical development, and (ii) further investigation and the development of other preclinical programs. Based on the reprioritization and other cost reductions, the Company believes it has sufficient cash to fund its projected operating requirements for at least twelve months from the date of issuance of the condensed consolidated financial statements. As of March 31, 2023, the Company had $ 54.3 million in cash, cash equivalents and short-term investments and no debt. However, the Company has experienced net losses and negative cash flows from operating activities since its inception and has an accumulated deficit of $ 169.8 million as of March 31, 2023. The Company expects to continue to incur net losses for the foreseeable future and believes it will need to raise substantial additional capital to accomplish its business plan over the next several years. The Company plans to continue to fund its losses from operations and capital funding needs through a combination of public or private equity or debt offerings or other sources, including potential collaborations, strategic alliances and other similar licensing arrangements. If the Company is unable to secure adequate additional funding, the Company may be forced to make reductions in spending, including potentially delaying, scaling back or eliminating certain of its pipeline development programs, extend payment terms with suppliers, or liquidate assets where possible. Any of these actions could materially affect the Company’s business, results of operations and future prospects. The Company's ability to obtain additional financing (including through collaboration and/or licensing arrangements) will depend on a number of factors, including, among others, its ability to generate positive data from its clinical trials and preclinical studies, the condition of the capital markets and other risks, many of which are dependent on factors outside of its control. There can be no assurance as to the availability or terms upon which such financing and capital might be available in the future. Notice of Delisting On April 4, 2023, the Company received a letter from the Nasdaq staff indicating that, for the last thirty consecutive business days, the bid price for Oncternal’s common stock had closed below the minimum $ 1.00 per share requirement for continued listing on The Nasdaq Capital Market. In accordance with Nasdaq listing rules, the Company has been provided an initial period of 180 calendar days, or until October 2, 2023, to regain compliance. The letter states that the Nasdaq staff will provide written notification that Oncternal has achieved compliance with its rules if at any time before October 2, 2023, the bid price of Oncternal’s common stock closes at $ 1.00 per share or more for a minimum of ten consecutive business days. The Nasdaq letter has no immediate effect on the listing or trading of Oncternal’s common stock and the common stock will continue to trade on The Nasdaq Capital Market. The Company has not regained compliance with Nasdaq listing rules as of the date these financial statements were issued. The Company intends to monitor the bid price of its common stock and consider available options if its common stock does not trade at a level likely to result in the Company regaining compliance with Nasdaq’s minimum bid price rule by October 2, 2023. If the Company does not regain compliance with Nasdaq listing rules by October 2, 2023, the Company may be eligible for an additional 180 calendar day compliance period. To qualify, the Company would be required to meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for The Nasdaq Capital Market, with the exception of the bid price requirement, and would need to provide written notice of its intention to cure the deficiency during the second compliance period, by effecting a reverse stock split, if necessary. However, if it appears to the Nasdaq staff that the Company will not be able to cure the deficiency, or if the Company is otherwise not eligible, the Nasdaq staff would notify the Company that its securities would be subject to delisting. In the event of such a notification, the Company may appeal the Nasdaq staff’s determination to delist its securities, but there can be no assurance the Nasdaq staff would grant the Company’s request for continued listing. Basis of Presentation The accompanying interim condensed financial statements are unaudited. The unaudited condensed consolidated financial statements have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (“SEC”) and with generally accepted accounting principles in the United States of America (“GAAP”). These unaudited condensed consolidated financial statements have been prepared on the same basis as the audited, consolidated financial statements and include all adjustments, consisting of only normal recurring accruals, which in the opinion of management are necessary to present fairly the Company’s financial position as of the interim date and results of operations for the interim periods presented. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ materially from those estimates. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements for the year ended December 31, 2022, filed with the SEC on its Annual Report on Form 10-K on March 9, 2023. The results presented in these unaudited condensed consolidated financial statements are not necessarily indicative of the results expected for the full fiscal year or any other interim period or any future year or period. Use of Estimates The Company’s condensed consolidated financial statements are prepared in accordance with GAAP. The preparation of the condensed consolidated financial statements and accompanying notes requires it to make estimates and assumptions that impact the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities. Significant estimates consist of those used to determine grant revenue and accruals for research and development costs. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions. Cash and Cash Equivalents The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, money market accounts and commercial paper. Short-term Investments The Company carries short-term investments classified as available-for-sale marketable securities at fair value as determined by prices for identical or similar securities at the balance sheet date. Short-term investments consist of Level 1 and Level 2 financial instruments in the fair value hierarchy (see Note 6). Realized gains or losses on available-for-sale securities are determined using the specific identification method and net realized gains and losses are included in interest income. The Company periodically reviews available-for-sale securities for other-than-temporary declines in fair value below the cost basis, and whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company records unrealized gains and losses on available-for-sale marketable securities as a component of other accumulated comprehensive income within the statements of operations and comprehensive loss and as a separate component of stockholders’ equity on the balance sheets. In accordance with policy, the Company does not invest in or hold equity securities in its investment portfolio. Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash balances due to the financial position of the depository institution in which those deposits are held. Additionally, the Company established guidelines regarding approved investments and maturities of investments, which are designed to maintain safety and liquidity. Research and Development Expenses and Accruals Research and development expenses consist of costs incurred for the Company’s own and for sponsored and collaborative research and development activities. Research and development costs are expensed as incurred and include manufacturing process development costs, manufacturing costs, costs associated with preclinical studies and clinical trials, regulatory and medical affairs activities, quality assurance activities, salaries and benefits, including stock-based compensation, fees paid to third-party consultants, license fees and overhead. The Company has entered into various research and development contracts with research institutions, clinical research organizations, clinical manufacturing organizations and other companies. Payments for these activities are based on the terms of the individual agreements, which may differ from the pattern of costs incurred, and payments made in advance of performance are reflected in the accompanying condensed consolidated balance sheets as prepaid expenses and other assets or accrued liabilities. The Company records accruals for estimated costs incurred for ongoing research and development activities and all clinical trial expenses are included in research and development expenses. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the services, including the phase or completion of events, invoices received and contracted costs. Significant judgments and estimates may be made in determining the prepaid or accrued balances at the end of any reporting period. Actual results could differ from the Company’s estimates. Fair Value Measurements The accounting guidance defines fair value, establishes a consistency framework for measuring fair value and expands disclosure for each major asset and liability category measured at fair value on either a recurring basis or nonrecurring basis. Fair value is defined as an exit price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. Accounting guidance establishes a three-tier fair value hierarchy that requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. These tiers are based on the source of the inputs and are as follows: Level 1: Observable inputs such as quoted prices in active markets for identical assets or liabilities. Level 2: Inputs other than quoted prices in active markets that are observable either directly or indirectly. Level 3: Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions. The Company’s financial instruments include cash, cash equivalents, short-term investments, prepaid expenses and other assets, accounts payable, accrued expenses, and accrued compensation. The carrying amounts of the Company’s current financial assets and liabilities are considered to be representative of their respective fair values because of the short-term nature of those instruments. The Company has short-term investments that are measured at fair value on a recurring basis. No transfers between levels have occurred during the periods presented (see Note 6). Net Loss Per Share Basic net loss per share is computed by dividing the net loss by the weighted-average number of common shares outstanding for the period, without consideration for potentially dilutive securities and adjusted for the weighted-average number of common shares outstanding that are subject to repurchase. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for the period determined using the treasury-stock and if-converted methods. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding as inclusion of the potentially dilutive securities would be antidilutive. Potentially dilutive securities not included in the calculation of diluted net loss per share, because to do so would be anti-dilutive, are as follows (in common stock equivalent shares; in thousands): March 31, 2023 2022 Warrants to purchase common stock 3,411 4,235 Common stock options 10,985 8,199 Restricted stock unit awards 753 464 Total 15,149 12,898 Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses: Measurement of Credit Losses on Financial Statements (Topic 326), which intends to improve financial reporting by requiring earlier recognition of credit losses on certain financial assets, such as available-for-sale debt securities. Topic 326 amends guidance on reporting credit losses for assets held at amortized cost basis and available-for-sale debt securities. For assets held at amortized cost basis, Topic 326 eliminates the probable initial recognition threshold in current GAAP and, instead, requires an entity to reflect its current estimate of all expected credit losses. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the financial assets to present the net amount expected to be collected. For available-for-sale debt securities, credit losses should be measured in a manner similar to current GAAP, however Topic 326 will require that credit losses be presented as an allowance rather than as a write-down. This ASU update affects entities holding financial assets and net investment in leases that are not accounted for at fair value through net loss. This update is effective for the Company and was adopted on January 1, 2023, which did not have a material impact on its condensed consolidated financial statements.

Balance Sheet Details

Balance Sheet Details	3 Months Ended
	Mar. 31, 2023
Payables and Accruals [Abstract]
Balance Sheet Details	2. Balance Sheet Details Prepaid and other consist of the following (in thousands): March 31, December 31, 2023 2022 Research and development $ 15 $ — Clinical trials 2,845 2,616 Insurance 321 669 Other prepaid expenses 137 103 Other receivable 282 178 $ 3,600 $ 3,566 Accrued liabilities consist of the following (in thousands): March 31, December 31, 2023 2022 Research and development $ 850 $ 972 Clinical trials 1,284 868 Legal fees 128 138 Compensation 1,110 2,691 Other 102 9 $ 3,474 $ 4,678

Marketable Securities

Marketable Securities	3 Months Ended
	Mar. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	3. Marketable Securities The Company invests in available-for-sale marketable securities consisting of money market funds, commercial paper, certificates of deposit, U.S. Treasury securities and U.S. government sponsored enterprise securities. Available-for-sale marketable securities are classified as part of either cash, cash equivalents or short-term investments in the balance sheets. Available-for-sale marketable securities with original maturities of more than three months from the date of purchase as of March 31, 2023 and December 31, 2022, have been classified as short-term investments and are measured at a fair value on a recurring basis, and were as follows (in thousands): As of March 31, 2023 Maturity (in years) Amortized Cost Unrealized Gains Unrealized Losses Fair Market Value Cash and cash equivalents: Money market funds 1 or less $ 8,967 $ — $ — $ 8,967 U.S. Treasury debt securities 1 or less 1,997 — — 1,997 Total cash and cash equivalents $ 10,964 $ — $ — $ 10,964 Short-term investments: U.S. Treasury debt securities 1 or less $ 36,131 $ 11 $ — $ 36,142 Commercial Paper 1 or less 4,952 — — 4,952 U.S. Government Agency 1 or less 1,979 — — 1,979 Total short-term investments $ 43,062 $ 11 $ — $ 43,073 Total marketable securities $ 54,026 $ 11 $ — $ 54,037 As of December 31, 2022 Maturity (in years) Amortized Cost Unrealized Gains Unrealized Losses Fair Market Value Cash and cash equivalents: Money market funds 1 or less $ 25,108 $ — $ — $ 25,108 U.S. Treasury debt securities 1 or less 1,996 — — 1,996 U.S. Government Agency 1 or less 1,991 — — 1,991 Total cash and cash equivalents $ 29,095 $ — $ — $ 29,095 Short-term investments: U.S. Treasury debt securities 1 or less $ 21,681 $ 7 $ — $ 21,688 Commercial Paper 1 or less 2,936 — — 2,936 U.S. Government Agency 1 or less 1,956 2 — 1,958 Total short-term investments $ 26,573 $ 9 $ — $ 26,582 Total marketable securities $ 55,668 $ 9 $ — $ 55,677 Effective January 1, 2023, at each reporting date the Company assesses available-for-sale debt securities in an unrealized loss position to determine whether the unrealized loss or any potential credit losses should be recognized in net loss. For available-for-sale debt securities in an unrealized loss position, the Company first assesses whether it intends to sell, or it is more likely than not that it will be required to sell, the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through net loss. For available-for-sale securities that do not meet the aforementioned criteria, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers the severity of the impairment, any changes in interest rates, underlying credit ratings, and forecasted recovery, among other factors. The credit-related portion of unrealized losses, and any subsequent improvements, are recorded as an allowance in interest income. There have been no impairment or credit losses recognized during the periods presented in the accompanying condensed consolidated statements of operations and comprehensive loss. The Company obtains the fair value of its available-for-sale marketable securities from a professional pricing service. The fair values of available-for-sale marketable securities are validated by comparing the fair values reported by the professional pricing service to quoted market prices or to fair values obtained from the custodian bank. The service provider values the securities using a hierarchical security pricing model that relies primarily on valuations provided by an industry-recognized valuation service or mathematical calculations. Such valuations may be based on trade prices in active markets for identical assets or liabilities (Level 1 inputs) or valuation models using inputs that are observable either directly or indirectly (Level 2 inputs), such as quoted prices for similar assets or liabilities, yield curves, credit spreads, current market and contractual prices for the underlying instruments or debt, as well as other relevant economic measures.

Commitments, Contingencies and

Commitments, Contingencies and Related Party Transactions	3 Months Ended
	Mar. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Related Party Transactions	Lease and Sublease Rent expense was $ 39,000 and $ 46,000 for the three months ended March 31, 2023 and 2022, respectively. From May 2019 through March 31, 2023, the Company leased or subleased office space in San Diego, California. On April 18, 2022, the Company entered into a sublease agreement for office space in San Diego, California which expires on July 31, 2023 (the “San Diego Lease”). Base rent under the San Diego Lease is approximately $ 157,000 annually and the monthly rent expense is being recognized on a straight-line basis over the term of the lease. The San Diego Lease is included in the accompanying condensed consolidated balance sheet at the present value of the lease payments. As the San Diego Lease does not have an implicit interest rate, the present value reflects a 10.0 % discount rate which is the estimated rate of interest that the Company would have to pay in order to borrow an amount equal to the lease payments on a collateralized basis over a similar term and in a similar economic environment. As of March 31, 2023, the Company has a net operating lease right-of-use asset and an aggregate lease liability of $ 50,000 , which has a weighted average remaining lease term of 0.3 years. Related Party Transactions Effective in September 2019, the Company and Shanghai Pharmaceutical (USA) Inc. (“SPH USA”) entered into a Materials and Supply and Services Agreement (“SPH USA Services Agreement”), pursuant to which the Company and SPH USA will execute various statements of work for the transfer to SPH USA of key reagents and other materials, and for the supply of certain services by the Company to SPH USA, as contemplated under and in furtherance of the License and Development Agreement between the Company and SPH USA effective as of November 2018. As of March 31, 2023 and December 31, 2022, the Company had no amounts receivable from SPH USA related to statements of work. SPH USA is the Company’s largest stockholder and an affiliate of one of the Company’s directors. The Company has an agreement with SPH USA for certain rights to the greater China area (see Note 5).

License, Collaboration and Gran

License, Collaboration and Grant Award/ Subaward Agreements	3 Months Ended
	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
License, Collaboration and Grant/ Subaward Agreements	5. License, Collaboration and Grant Award/Subaward Agreements Georgetown University (“Georgetown”) In March 2014, the Company entered into an Exclusive License Agreement (the “Georgetown License Agreement”) with Georgetown, pursuant to which the Company: (i) licensed the exclusive worldwide right to patents and technologies for the development and commercialization of certain product candidates targeting EWS-FLI1 as an anti-tumor therapy for therapeutic, diagnostics, or research tool purposes, (ii) is solely responsible for all development and commercialization activities and costs, and (iii) is responsible for all costs related to the filing, prosecution and maintenance of the licensed patent rights. Under the terms of the Georgetown License Agreement, commencing in 2015, the Company: (i) shall pay and has paid an annual license maintenance fee of $ 10,000 until the first commercial sale occurs, (ii) is required to make up to $ 0.2 million in aggregate milestone payments upon the achievement of certain regulatory milestones, and (iii) will be required to pay low single digit royalties based on annual net product sales. The Company accounted for the licensed technology as an asset acquisition because it did not meet the definition of a business. All milestone payments under the Georgetown License Agreement will be recognized as research and development expense upon completion of the required events, as the triggering events are not considered to be probable until they are achieved. As of March 31, 2023, the Company had not triggered or made any milestone payments under the Georgetown License Agreement. The Georgetown License Agreement may be terminated by either party upon material breach or may be terminated by the Company as to one or more countries with 90 days written notice of termination. The term of the Georgetown License Agreement will continue until the expiration of the last valid claim within the patent rights covering the product. Georgetown may terminate the agreement in the event: (i) the Company fails to pay any amount and fails to cure such failure within 30 days after receipt of notice, (ii) the Company defaults in its obligation to obtain and maintain insurance and fails to remedy such breach within 60 days after receipt of notice, or (iii) the Company declares insolvency or bankruptcy. The Company may terminate the Georgetown License Agreement at any time upon at least 60 days’ written notice. The University of Texas MD Anderson Cancer Center (“MD Anderson”) In December 2014, the Company entered into a collaboration agreement (as amended, the “Collaboration”) with MD Anderson, which provides for the conduct of preclinical and clinical research for ONCT-216 in exchange for certain program payments. If MD Anderson successfully completes all the requirements of the Collaboration in full and the program is successfully commercialized, the Company will be required to pay aggregate milestone payments of $ 1.0 million based on net product sales. In July 2020 and September 2021, the Company entered into two research agreements with MD Anderson for certain services up to an aggregate cost of $ 0.8 million. The Company recorded research and development expense of no ne and $ 0.1 million for each of the three months ended March 31, 2023 and 2022, respectively. Agreements with the Regents of the University of California (the “Regents”) In March 2016, and as amended and restated in August 2018, and as amended thereafter, the Company and the Regents entered into a license agreement (as amended and restated, the “Regents License Agreement”) for the development, manufacturing and distribution rights related to the development and commercialization of ROR1 related naked antibodies, antibody fragments or synthetic antibodies, and genetically engineered cellular therapy. The Regents License Agreement provides for the following: (i) in May 2016, an upfront license fee of $ 0.5 million was paid and 107,108 shares of common stock were issued, (ii) $ 25,000 in annual license maintenance fees commencing in 2017, (iii) reimbursement of certain annual patent costs, (iv) certain development and regulatory milestones aggregating from $ 20.1 million to $ 24.5 million, on a per product basis, (v) certain worldwide sales milestones based on achievement of tiered revenue levels aggregating $ 75.0 million, (vi) low single-digit royalties, including potential future minimum annual royalties, on net sales of each target, and (vii) minimum diligence to advance licensed assets consisting of at least $ 1.0 million in development spend annually through 2021. Under the Regents License Agreement, the Company recorded: (a) $ 5,000 and $ 25,000 in license maintenance fees as research and development expense for the three months ended March 31, 2023 and 2022, respectively, and (b) a nominal amount in patent costs as general and administrative expense for each of the three months ended March 31, 2023 and 2022, respectively. As of March 31, 2023, the Company believes it has met its obligations under the Regents License Agreement. The Regents License Agreement will expire upon the later of the expiration date of the longest-lived patent rights or the 15th anniversary of the first commercial sale of a licensed product. The Regents may terminate the Regents License Agreement if: (i) a material breach by the Company is not cured within a reasonable time, (ii) the Company files a claim asserting the Regents licensed patent rights are invalid or unenforceable, and (iii) the Company files for bankruptcy. The Company may terminate the agreement at any time upon at least 60 days’ written notice. Effective January 1, 2022, the Company entered into a Research Agreement (the “Research Agreement”) with the Regents for further research on the ROR1 therapeutic development program. Under this four-year agreement that expires on December 31, 2025, the Regents will have an aggregate budget of $ 1.6 million, with quarterly payments of $ 125,000 in 2022, $ 131,250 in 2023, and $ 137,813 in 2024. The Company recorded $ 0.1 million in research and development expenses under these agreements for the three months ended March 31, 2023 and 2022, respectively. Such costs are includable as part of the Company’s annual diligence obligations under the Regents License Agreement. The University of Tennessee Research Foundation (“UTRF”) In March 2015, and as amended and restated in March 2022 and August 2022, the Company and UTRF entered into a license agreement (the “DAARI License Agreement”) pursuant to which the Company was granted exclusive worldwide rights in all existing selective androgen receptor degrader technologies owned or controlled by UTRF, including all improvements thereto, which is now known as the dual action androgen receptor inhibitor, or DAARI program. Under the DAARI License Agreement, the Company is obligated to employ active, diligent efforts to conduct preclinical research and development activities for the DAARI program to advance one or more lead compounds into clinical development. The Company is also obligated to pay UTRF annual license maintenance fees, low single-digit royalties on net sales of products and additional royalties on sublicense revenues, depending on the state of development of a clinical product candidate at the time it is sublicensed. The Company recorded research and development expense under this agreement of a nominal amount and $ 0.2 million for the three months ended March 31, 2023 and 2022, respectively. As of March 31, 2023, the Company believes it has met its obligations under the DAARI License Agreement. The California Institute for Regenerative Medicine (“CIRM”) Award In August 2017, and as amended and restated in December 2020, CIRM awarded an $ 18.3 million grant to researchers at UC San Diego to advance the Company’s Phase 1/2 clinical trial evaluating zilovertamab in combination with ibrutinib for the treatment of patients with B-cell lymphoid malignancies, including MCL and CLL. This study is known as CIRM-0001, or Cirmtuzumab and Ibrutinib for Relapsed Lymphoma or Leukemia (the “CIRLL study”). The Company: (i) conducted this study in collaboration with UC San Diego, (ii) received $ 14.5 million in development milestones under research subaward agreements during the award project period from October 1, 2017 through March 31, 2022, (iii) was committed to and met certain co-funding requirements, (iv) received no subaward payments in the three months ended March 31, 2022, and (v) was required to provide UC San Diego progress and financial update reports throughout the award period. The subaward does not bear a royalty payment commitment, nor is the subaward otherwise refundable. As of March 31, 2023, the Company believes it has met its obligations under the CIRM award and UC San Diego subawards. The National Institutes of Health (“NIH”) Grant Awards In August 2021, the NIH awarded the Company two research and development grants for up to $ 2.2 million to support pre-clinical activities for the Company’s ONCT-216 and DAARI programs, including $ 0.7 million payable to subawardees. In March 2023, the NIH awarded the Company a research and development grant for up to $ 1.8 million to support pre-clinical activities for the Company’s DAARI program, including $ 0.3 million payable to subawardees. Under the terms of the grants, the Company is entitled to receive reimbursement in arrears of incurring allowable expenditures. The earned NIH funds are non-refundable and the Company is required to provide periodic progress performance reports. During the three months ended March 31, 2023 and 2022, the Company received $ 0.1 million and $ 0.1 million in award payments and recorded $ 0.2 million and $ 0.5 million in grant revenue, respectively. As of March 31, 2023 and December 31, 2022, the Company had an unbilled grant receivable of $ 0.1 million, respectively, which has been included in prepaid and other assets. Clinical Trial and Supply Agreements In April 2018, and as amended in August 2019, the Company entered into a Clinical Trial and Supply Agreement with Pharmacyclics, LLC, an AbbVie Company, to supply ibrutinib for the Phase 1/2 study CIRM-0001. Effective in June 2022, the Company entered into a Clinical Trial and Supply Agreement with Pharmacyclics, LLC, to supply ibrutinib for the Company’s Phase 3 study ZILO-301. Such agreement does not bear any upfront costs, inventory purchase costs, milestone or royalty payment commitments or other financial obligations. In April 2023, the Company reprioritized the development of zilovertamab and closed the Phase 3 ZILO-301 and the Phase 1/2 CIRM-0001 studies. License and Development Agreement (“LDA”) with SPH USA, a Related Party In November 2018, and as amended in August 2020, the Company entered into the LDA with SPH USA for: (i) the territory of the People’s Republic of China, Hong Kong, Macau, and Taiwan (“Greater China”), and (ii) rights to manufacture, develop, market, distribute and sell all of the Company’s product candidates under the Georgetown License Agreement and the Regents License Agreement (exclusive to Greater China only). Under the LDA, SPH USA is solely responsible for: (a) all preclinical and clinical development activities required in order to obtain regulatory approval in Greater China for such product candidates, (b) any third-party license milestone or royalty payments owed under the Georgetown License Agreement and the Regents License Agreement, and (c) paying the Company a low single digit royalty on net sales in the territory. The LDA will expire upon the expiration of the last royalty term for the last licensed product. The LDA may be terminated by: (i) SPH USA on a country by country or product by product basis with 180 days written notice, (ii) either party upon material breach that is not cured within 90 days, and (iii) either party in the event the other party declares insolvency or bankruptcy. There has been no significant activity under this agreement for each of the three months ended March 31, 2023 and 2022 (see Note 4). Contingent Value Rights Agreement (“CVR Agreement”) Pursuant to the GTx merger agreement entered into in June 2019 (the “Merger”), the Company, a representative of holders of the CVRs, and Computershare, Inc. as rights agent, entered into the CVR Agreement. Pursuant to the CVR Agreement, the Company’s stockholders of record as of immediately prior to the Merger received one CVR for each share of the Company’s common stock held immediately prior to the Merger. As amended on November 1, 2021, the CVR Agreement entitles holders of CVRs to receive: (i) 50% of certain net proceeds received by the Company during the 15 -year period after the closing of the Merger (the “CVR Term”) from a transaction, if any, resulting in the grant, sale, or transfer of DAARI technology to a third party that occurs during the 10 -year period after the closing of the Merger (or in the 11th year if based on a term sheet approved during the initial 10-year period); and (ii) 5 % of net sales of products by Parent or its affiliates during the CVR Term incorporating the DAARI technology. As of March 31, 2023, no transactions or net sales relating to the DAARI technology had occurred.

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value	6. Fair Value As of March 31, 2023 and December 31, 2022, the following fair value hierarchy table presents the Company’s financial assets measured at fair value on a recurring basis (in thousands): Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs As of March 31, 2023 Assets: Cash and cash equivalents: Money market funds $ 8,967 $ 8,967 $ — $ — U.S. Treasury debt securities 1,997 1,997 — — Total cash and cash equivalents $ 10,964 $ 10,964 $ — $ — Short-term investments: U.S. Treasury debt securities $ 36,142 $ 36,142 $ — $ — Commercial Paper 4,952 — 4,952 — U.S. Government Agency 1,979 — 1,979 — Total short-term investments $ 43,073 $ 36,142 $ 6,931 $ — Total assets measured at fair value $ 54,037 $ 47,106 $ 6,931 $ — Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs As of December 31, 2022 Assets: Cash and cash equivalents: Money market funds $ 25,108 $ 25,108 $ — $ — U.S. Treasury debt securities 1,996 1,996 — — U.S. Government Agency 1,991 — 1,991 — Total cash and cash equivalents $ 29,095 $ 27,104 $ 1,991 $ — Short-term investments: U.S. Treasury debt securities $ 21,688 $ 21,688 $ — $ — Commercial Paper 2,936 — 2,936 — U.S. Government Agency 1,958 — 1,958 — Total short-term investments $ 26,582 $ 21,688 $ 4,894 $ — Total assets measured at fair value $ 55,677 $ 48,792 $ 6,885 $ — The Company’s policy is to recognize transfers between levels of the fair value hierarchy on the date of the event or change in circumstances that caused the transfer. There were no transfers into or out of Level 3 during the three months ended March 31, 2023 and 2022.

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2023
Equity [Abstract]
Stockholders' Equity	7. Stockholders’ Equity ATM Program In December 2021, the Company entered into an Open Market Sale Agreement SM (the “Sales Agreement”) with Jefferies LLC, pursuant to which the Company is able to offer and sell, from time to time in its sole discretion, shares of its common stock having an aggregate offering price of up to $ 50.0 million. The Company has no obligation to sell any shares under the Sales Agreement and may at any time suspend solicitation and offers under the Sales Agreement. During the three months ended March 31, 2023, the Company sold 1,115,480 shares of common stock for net proceeds of $ 1.2 million. Common Stock Warrants A summary of warrant activity and changes in warrants outstanding is presented below: Number of Shares Underlying Warrants Weighted-Average Exercise Price Per Share Weighted-Average Remaining Contractual Term (in years) Balance at December 31, 2022 3,410,642 $ 3.70 2.94 Issued — $ — — Forfeited — $ — — Exercised — $ — — Balance at March 31, 2023 3,410,642 $ 3.70 2.69 All warrants met the criteria for classification in stockholders’ equity. Equity Incentive Plans Stock Option Awards Contemporaneous with the Merger closing: (i) Oncternal’s 2015 Equity Incentive Plan, as amended (“2015 Plan”) was assumed by the Company, and (ii) the Company adopted the 2019 Incentive Award Plan (“2019 Plan”) under which the sum of: (a) 1,954,150 shares of common stock, and (b) an annual increase on the first day of each calendar year beginning January 1, 2020, and ending on and including January 1, 2029, equal to the lesser of (A) 5 % of the aggregate number of shares of common stock outstanding on the final day of the immediately preceding calendar year and (B) such smaller number of shares of common stock as is determined by the Board, are reserved for issuance. In July 2015, Oncternal adopted the 2015 Plan which provided for the issuance of shares of common stock for incentive stock options, non-statutory stock options, restricted stock awards, restricted stock unit awards and other stock awards to its employees, members of its board of directors and consultants. In general, the options issued under the 2015 Plan expire ten years from the date of grant and vest over a four-year period. Certain grants vest based on the achievement of development or regulatory milestones. The 2015 Plan was terminated as to new grant awards in June 2019. The 2019 Plan provides for the issuance of shares of common stock for incentive stock options, non-statutory stock options, restricted stock awards, restricted stock unit awards and other stock awards to its employees, members of its board of directors and consultants. In general, the stock options issued under the 2019 Plan expire ten years from the date of grant and vest over a four-year period. Certain stock option grants vest based on the achievement of development or regulatory milestones. The 2019 Plan allows for the early exercise of all stock option grants if authorized by the board of directors at the time of grant. In February 2021, the Company’s board of directors adopted the 2021 Employment Inducement Incentive Award Plan (the “Inducement Plan”). The Inducement Plan is a non-shareholder approved stock plan adopted pursuant to the “inducement exception” provided under Nasdaq listing rules. The Inducement Plan is used exclusively for the issuance of non-statutory stock options to certain new hires who satisfied the requirements to be granted inducement grants under Nasdaq rules as an inducement material to the individual’s entry into employment with the Company. The terms of the Inducement Plan are substantially similar to the terms of the 2019 Plan. As amended in May 2021 and December 2021, the Company has reserved 2,800,000 shares of common stock under the Inducement Plan. As of March 31, 2023, 1,757,954 shares remain available for issuance under the 2019 Plan and Inducement Plan. A summary of the Company’s stock option activity under the 2015 Plan, 2019 Plan and Inducement Plan is as follows: Number of Options Weighted-Average Exercise Price Weighted-Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Outstanding at December 31, 2022 8,515,696 $ 4.16 8.1 $ 101,611 Granted 2,654,000 $ 0.97 Forfeited ( 184,347 ) $ 3.72 Outstanding at March 31, 2023 10,985,349 $ 3.40 7.5 $ 13,254 Options vested and expected to vest as of March 31, 2023 10,985,349 $ 3.40 7.5 $ 13,254 Options vested and exercisable as of March 31, 2023 4,349,256 $ 4.51 6.8 $ 13,254 For the three months ended March 31, 2023 and 2022, the weighted average grant date fair value per share of option grants was $ 0.78 and $ 1.54 , respectively. The intrinsic value is calculated as the difference between the fair value of the Company’s common stock at the time of the option exercise and the exercise price of that stock option. For the three months ended March 31, 2023 and 2022, no stock options were exercised. Restricted Stock Unit Awards Restricted stock unit awards (“RSUs”) are rights to receive shares of the Company’s common stock upon satisfaction of specific vesting conditions. The Company began issuing RSUs in the first quarter of 2022. The RSUs generally vest over a two-year period. Restricted stock unit activity under Equity Incentive Plans is summarized as follows: Number of Restricted Stock Units Weighted-Average Remaining Contractual Term (in years) Weighted-Average Grant Date Fair Value Nonvested at December 31, 2022 1,009,083 0.6 $ 1.64 Granted — Vested ( 217,676 ) $ 2.43 Forfeited/ Repurchased ( 38,432 ) $ 1.27 Nonvested at March 31, 2023 752,975 0.5 $ 1.43 Units expected to vest as of March 31, 2023 747,456 0.5 $ 1.42 The fair value of RSUs vested during the three months ended March 31, 2023 was $ 0.2 million. Stock-Based Compensation Expense The weighted-average assumptions used in the Black-Scholes option pricing model to determine the fair value of stock option grants, were as follows: Three Months Ended March 31, 2023 2022 Risk-free interest rate 4.1 % 1.7 % Expected volatility 99.8 % 100.4 % Expected term (in years) 6.1 6.2 Expected dividend yield — % — % Expected volatility. The expected volatility assumption is based on a blend of volatilities of the Company’s share price and a peer group of similar companies whose share prices are publicly available. The volatility of the Company’s shares price was measured using the closing share price beginning June 10, 2019, the date of the closing of the Merger, through the current period. The peer group was developed based on companies in the life sciences industry with comparable characteristics to the Company including enterprise value, risk profiles, position within the industry, and with historical share price information sufficient to meet the expected life of the stock-based awards. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available. Expected term. The expected term represents the period of time that options are expected to be outstanding. Due to limited historical exercise behavior, it determined the expected life assumption using the simplified method for employees, which is an average of the contractual term of the option and its vesting period. The expected term for nonemployee options is generally the remaining contractual term. Risk-free interest rate. The risk-free interest rate is based on the implied yield on the U.S. Treasury securities with a maturity date similar to the expected term of the associated stock option award. Expected dividend yield. The Company bases the expected dividend yield assumption on the fact that it has never paid cash dividends and has no present intention to pay cash dividends and, therefore, used an expected dividend yield of zero. RSU awards represent rights to receive shares of common stock contingent upon satisfaction of specific vesting conditions. The stock-based compensation expense for these awards was determined using the closing price on the grant date applied to the total number of shares that were anticipated to fully vest. Stock-based compensation expense recognized for all equity awards has been reported in the condensed consolidated statements of operations as follows (in thousands): Three Months Ended March 31, 2023 2022 Research and development $ 1,117 $ 1,063 General and administrative 768 915 $ 1,885 $ 1,978 As of March 31, 2023, the unrecognized compensation cost related to non-vested stock options was $ 12.5 million, which is expected to be recognized over a weighted-average period of 3.0 years. As of March 31, 2023, the unrecognized compensation cost related to non-vested restricted stock units was $ 0.7 million, which is expected to be recognized over a weighted-average period of 0.8 year. Common Stock Reserved for Future Issuance Common stock reserved for future issuance is as follows (in thousands): March 31, Common stock warrants 3,411 Common stock options issued and outstanding 10,985 Restricted stock unit awards unvested and outstanding 753 Common stock available for issuance under the Inducement Plan and 2019 Plan 1,758 16,907

COVID-19 Pandemic and CARES Act

COVID-19 Pandemic and CARES Act	3 Months Ended
	Mar. 31, 2023
C O V I D19 Pandemic And C A R E S Act [Abstract]
COVID-19 Pandemic and CARES Act	8. COVID-19 Pandemic and CARES Act The COVID-19 pandemic has presented substantial public health and economic challenges and continues to affect economies, financial markets and business operations around the world. The pandemic may continue to directly or indirectly affect the timeline for the Company’s preclinical and manufacturing activities, planned regulatory submissions and clinical trials. The Company considered the impacts of COVID-19 on the assumptions and estimates used to prepare its condensed consolidated financial statements and determined that there were no material adverse impacts on the Company’s results of operations and financial position at March 31, 2023. The full extent to which the COVID-19 pandemic will continue to directly or indirectly impact the Company’s business results of operations and financial condition, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain or treat it, the success or failure of ongoing vaccination programs, the emergence and spread of additional variants of COVID-19, as well as the economic impact on local, regional, national and international markets. In response to the COVID-19 pandemic, the CARES Act was signed into law on March 27, 2020. The CARES Act, among other things, includes tax provisions relating to refundable payroll tax credits, deferment of employer’s social security payments, net operating loss utilization and carryback periods, modifications to the net interest deduction limitations and technical corrections to tax depreciation methods for qualified improvement property, and authorized the Paycheck Protection Program. The CARES Act had no material impact on the Company’s income tax provision for the three months ended March 31, 2023. The Company continues to monitor changes and revisions to the CARES Act and its impact on the Company’s condensed consolidated financial position, results of operations and cash flows. 9. Subsequent Event On April 3, 2023, the Company announced a strategic reprioritization based on the rapidly changing commercial landscape for Bruton’s tyrosine kinase inhibitors resulting in the Company's decision to close two studies: Study ZILO-301, a randomized, double-blind, placebo-controlled global Phase 3 registrational study evaluating zilovertamab in combination with ibrutinib for the treatment of patients with relapsed or refractory MCL, and Study CIRM-0001, a Phase 1/2 clinical trial evaluating zilovertamab in combination with ibrutinib for the treatment of patients with MCL, CLL or MZL.

Subsequent Event

Subsequent Event	3 Months Ended
	Mar. 31, 2023
Subsequent Events [Abstract]
Subsequent Event	9. Subsequent Event On April 3, 2023, the Company announced a strategic reprioritization based on the rapidly changing commercial landscape for Bruton’s tyrosine kinase inhibitors resulting in the Company's decision to close two studies: Study ZILO-301, a randomized, double-blind, placebo-controlled global Phase 3 registrational study evaluating zilovertamab in combination with ibrutinib for the treatment of patients with relapsed or refractory MCL, and Study CIRM-0001, a Phase 1/2 clinical trial evaluating zilovertamab in combination with ibrutinib for the treatment of patients with MCL, CLL or MZL.

Description of Business, Basi_2

Description of Business, Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2023
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries, Oncternal Oncology, Inc. and Oncternal, Inc. All intercompany accounts and transactions have been eliminated in the preparation of the condensed consolidated financial statements.
Liquidity	Liquidity From inception, the Company has devoted substantially all of its efforts to drug discovery and development and conducting preclinical studies and clinical trials. The Company has a limited operating history and the sales and income potential of the Company’s business and market are unproven. Successful transition to attaining profitable operations is dependent upon achieving a level of revenues adequate to support the Company’s cost structure. As a result of the strategic reprioritization announced in April 2023, the Company expects research and development expenses will decrease in future quarters after the closure of the Phase 3 ZILO-301 Study for the treatment of patients with relapsed or refractory MCL and the Phase 1/2 CIRM-0001 Study for the treatment of mantle cell lymphoma (“MCL”), chronic lymphocytic leukemia ( “CLL”) and marginal zone lymphoma (“MZL”), and the implementation of other cost reductions (see Note 9). The Company will continue to invest in: (i) advancing existing product candidates into later stages of clinical development, and (ii) further investigation and the development of other preclinical programs. Based on the reprioritization and other cost reductions, the Company believes it has sufficient cash to fund its projected operating requirements for at least twelve months from the date of issuance of the condensed consolidated financial statements. As of March 31, 2023, the Company had $ 54.3 million in cash, cash equivalents and short-term investments and no debt. However, the Company has experienced net losses and negative cash flows from operating activities since its inception and has an accumulated deficit of $ 169.8 million as of March 31, 2023. The Company expects to continue to incur net losses for the foreseeable future and believes it will need to raise substantial additional capital to accomplish its business plan over the next several years. The Company plans to continue to fund its losses from operations and capital funding needs through a combination of public or private equity or debt offerings or other sources, including potential collaborations, strategic alliances and other similar licensing arrangements. If the Company is unable to secure adequate additional funding, the Company may be forced to make reductions in spending, including potentially delaying, scaling back or eliminating certain of its pipeline development programs, extend payment terms with suppliers, or liquidate assets where possible. Any of these actions could materially affect the Company’s business, results of operations and future prospects. The Company's ability to obtain additional financing (including through collaboration and/or licensing arrangements) will depend on a number of factors, including, among others, its ability to generate positive data from its clinical trials and preclinical studies, the condition of the capital markets and other risks, many of which are dependent on factors outside of its control. There can be no assurance as to the availability or terms upon which such financing and capital might be available in the future.
Notice of Delisting	Notice of Delisting On April 4, 2023, the Company received a letter from the Nasdaq staff indicating that, for the last thirty consecutive business days, the bid price for Oncternal’s common stock had closed below the minimum $ 1.00 per share requirement for continued listing on The Nasdaq Capital Market. In accordance with Nasdaq listing rules, the Company has been provided an initial period of 180 calendar days, or until October 2, 2023, to regain compliance. The letter states that the Nasdaq staff will provide written notification that Oncternal has achieved compliance with its rules if at any time before October 2, 2023, the bid price of Oncternal’s common stock closes at $ 1.00 per share or more for a minimum of ten consecutive business days. The Nasdaq letter has no immediate effect on the listing or trading of Oncternal’s common stock and the common stock will continue to trade on The Nasdaq Capital Market. The Company has not regained compliance with Nasdaq listing rules as of the date these financial statements were issued. The Company intends to monitor the bid price of its common stock and consider available options if its common stock does not trade at a level likely to result in the Company regaining compliance with Nasdaq’s minimum bid price rule by October 2, 2023. If the Company does not regain compliance with Nasdaq listing rules by October 2, 2023, the Company may be eligible for an additional 180 calendar day compliance period. To qualify, the Company would be required to meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for The Nasdaq Capital Market, with the exception of the bid price requirement, and would need to provide written notice of its intention to cure the deficiency during the second compliance period, by effecting a reverse stock split, if necessary. However, if it appears to the Nasdaq staff that the Company will not be able to cure the deficiency, or if the Company is otherwise not eligible, the Nasdaq staff would notify the Company that its securities would be subject to delisting. In the event of such a notification, the Company may appeal the Nasdaq staff’s determination to delist its securities, but there can be no assurance the Nasdaq staff would grant the Company’s request for continued listing.
Basis of Presentation	Basis of Presentation The accompanying interim condensed financial statements are unaudited. The unaudited condensed consolidated financial statements have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (“SEC”) and with generally accepted accounting principles in the United States of America (“GAAP”). These unaudited condensed consolidated financial statements have been prepared on the same basis as the audited, consolidated financial statements and include all adjustments, consisting of only normal recurring accruals, which in the opinion of management are necessary to present fairly the Company’s financial position as of the interim date and results of operations for the interim periods presented. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ materially from those estimates. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements for the year ended December 31, 2022, filed with the SEC on its Annual Report on Form 10-K on March 9, 2023. The results presented in these unaudited condensed consolidated financial statements are not necessarily indicative of the results expected for the full fiscal year or any other interim period or any future year or period.
Use of Estimates	Use of Estimates The Company’s condensed consolidated financial statements are prepared in accordance with GAAP. The preparation of the condensed consolidated financial statements and accompanying notes requires it to make estimates and assumptions that impact the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities. Significant estimates consist of those used to determine grant revenue and accruals for research and development costs. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions. Cash and Cash Equivalents The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, money market accounts and commercial paper.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, money market accounts and commercial paper.
Short-term Investments	Short-term Investments The Company carries short-term investments classified as available-for-sale marketable securities at fair value as determined by prices for identical or similar securities at the balance sheet date. Short-term investments consist of Level 1 and Level 2 financial instruments in the fair value hierarchy (see Note 6). Realized gains or losses on available-for-sale securities are determined using the specific identification method and net realized gains and losses are included in interest income. The Company periodically reviews available-for-sale securities for other-than-temporary declines in fair value below the cost basis, and whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company records unrealized gains and losses on available-for-sale marketable securities as a component of other accumulated comprehensive income within the statements of operations and comprehensive loss and as a separate component of stockholders’ equity on the balance sheets. In accordance with policy, the Company does not invest in or hold equity securities in its investment portfolio.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash balances due to the financial position of the depository institution in which those deposits are held. Additionally, the Company established guidelines regarding approved investments and maturities of investments, which are designed to maintain safety and liquidity.
Research and Development Expenses and Accruals	Research and Development Expenses and Accruals Research and development expenses consist of costs incurred for the Company’s own and for sponsored and collaborative research and development activities. Research and development costs are expensed as incurred and include manufacturing process development costs, manufacturing costs, costs associated with preclinical studies and clinical trials, regulatory and medical affairs activities, quality assurance activities, salaries and benefits, including stock-based compensation, fees paid to third-party consultants, license fees and overhead. The Company has entered into various research and development contracts with research institutions, clinical research organizations, clinical manufacturing organizations and other companies. Payments for these activities are based on the terms of the individual agreements, which may differ from the pattern of costs incurred, and payments made in advance of performance are reflected in the accompanying condensed consolidated balance sheets as prepaid expenses and other assets or accrued liabilities. The Company records accruals for estimated costs incurred for ongoing research and development activities and all clinical trial expenses are included in research and development expenses. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the services, including the phase or completion of events, invoices received and contracted costs. Significant judgments and estimates may be made in determining the prepaid or accrued balances at the end of any reporting period. Actual results could differ from the Company’s estimates.
Fair Value Measurements	Fair Value Measurements The accounting guidance defines fair value, establishes a consistency framework for measuring fair value and expands disclosure for each major asset and liability category measured at fair value on either a recurring basis or nonrecurring basis. Fair value is defined as an exit price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. Accounting guidance establishes a three-tier fair value hierarchy that requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. These tiers are based on the source of the inputs and are as follows: Level 1: Observable inputs such as quoted prices in active markets for identical assets or liabilities. Level 2: Inputs other than quoted prices in active markets that are observable either directly or indirectly. Level 3: Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions. The Company’s financial instruments include cash, cash equivalents, short-term investments, prepaid expenses and other assets, accounts payable, accrued expenses, and accrued compensation. The carrying amounts of the Company’s current financial assets and liabilities are considered to be representative of their respective fair values because of the short-term nature of those instruments. The Company has short-term investments that are measured at fair value on a recurring basis. No transfers between levels have occurred during the periods presented (see Note 6).
Net Loss Per Share	Net Loss Per Share Basic net loss per share is computed by dividing the net loss by the weighted-average number of common shares outstanding for the period, without consideration for potentially dilutive securities and adjusted for the weighted-average number of common shares outstanding that are subject to repurchase. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for the period determined using the treasury-stock and if-converted methods. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding as inclusion of the potentially dilutive securities would be antidilutive. Potentially dilutive securities not included in the calculation of diluted net loss per share, because to do so would be anti-dilutive, are as follows (in common stock equivalent shares; in thousands): March 31, 2023 2022 Warrants to purchase common stock 3,411 4,235 Common stock options 10,985 8,199 Restricted stock unit awards 753 464 Total 15,149 12,898
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses: Measurement of Credit Losses on Financial Statements (Topic 326), which intends to improve financial reporting by requiring earlier recognition of credit losses on certain financial assets, such as available-for-sale debt securities. Topic 326 amends guidance on reporting credit losses for assets held at amortized cost basis and available-for-sale debt securities. For assets held at amortized cost basis, Topic 326 eliminates the probable initial recognition threshold in current GAAP and, instead, requires an entity to reflect its current estimate of all expected credit losses. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the financial assets to present the net amount expected to be collected. For available-for-sale debt securities, credit losses should be measured in a manner similar to current GAAP, however Topic 326 will require that credit losses be presented as an allowance rather than as a write-down. This ASU update affects entities holding financial assets and net investment in leases that are not accounted for at fair value through net loss. This update is effective for the Company and was adopted on January 1, 2023, which did not have a material impact on its condensed consolidated financial statements.

Description of Business, Basi_3

Description of Business, Basis of Presentation and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss per Share Would Be Anti-dilutive	Potentially dilutive securities not included in the calculation of diluted net loss per share, because to do so would be anti-dilutive, are as follows (in common stock equivalent shares; in thousands): March 31, 2023 2022 Warrants to purchase common stock 3,411 4,235 Common stock options 10,985 8,199 Restricted stock unit awards 753 464 Total 15,149 12,898

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	3 Months Ended
	Mar. 31, 2023
Payables and Accruals [Abstract]
Schedule of Prepaid and Other	Prepaid and other consist of the following (in thousands): March 31, December 31, 2023 2022 Research and development $ 15 $ — Clinical trials 2,845 2,616 Insurance 321 669 Other prepaid expenses 137 103 Other receivable 282 178 $ 3,600 $ 3,566
Summary of Accrued Liabilities	Accrued liabilities consist of the following (in thousands): March 31, December 31, 2023 2022 Research and development $ 850 $ 972 Clinical trials 1,284 868 Legal fees 128 138 Compensation 1,110 2,691 Other 102 9 $ 3,474 $ 4,678

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Schedule of Short-term Investments and are Measured at a Fair Value on a Recurring Basis	As of March 31, 2023 Maturity (in years) Amortized Cost Unrealized Gains Unrealized Losses Fair Market Value Cash and cash equivalents: Money market funds 1 or less $ 8,967 $ — $ — $ 8,967 U.S. Treasury debt securities 1 or less 1,997 — — 1,997 Total cash and cash equivalents $ 10,964 $ — $ — $ 10,964 Short-term investments: U.S. Treasury debt securities 1 or less $ 36,131 $ 11 $ — $ 36,142 Commercial Paper 1 or less 4,952 — — 4,952 U.S. Government Agency 1 or less 1,979 — — 1,979 Total short-term investments $ 43,062 $ 11 $ — $ 43,073 Total marketable securities $ 54,026 $ 11 $ — $ 54,037 As of December 31, 2022 Maturity (in years) Amortized Cost Unrealized Gains Unrealized Losses Fair Market Value Cash and cash equivalents: Money market funds 1 or less $ 25,108 $ — $ — $ 25,108 U.S. Treasury debt securities 1 or less 1,996 — — 1,996 U.S. Government Agency 1 or less 1,991 — — 1,991 Total cash and cash equivalents $ 29,095 $ — $ — $ 29,095 Short-term investments: U.S. Treasury debt securities 1 or less $ 21,681 $ 7 $ — $ 21,688 Commercial Paper 1 or less 2,936 — — 2,936 U.S. Government Agency 1 or less 1,956 2 — 1,958 Total short-term investments $ 26,573 $ 9 $ — $ 26,582 Total marketable securities $ 55,668 $ 9 $ — $ 55,677 Effective January 1, 2023, at each reporting date the Company assesses available-for-sale debt securities in an unrealized loss position to determine whether the unrealized loss or any potential credit losses should be recognized in net loss. For available-for-sale debt securities in an unrealized loss position, the Company first assesses whether it intends to sell, or it is more likely than not that it will be required to sell, the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through net loss. For available-for-sale securities that do not meet the aforementioned criteria, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers the severity of the impairment, any changes in interest rates, underlying credit ratings, and forecasted recovery, among other factors. The credit-related portion of unrealized losses, and any subsequent improvements, are recorded as an allowance in interest income. There have been no impairment or credit losses recognized during the periods presented in the accompanying condensed consolidated statements of operations and comprehensive loss.

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2023
Fair Value Disclosures [Abstract]
Schedule of Companys Assets Measured at Fair Value on Recurring Basis	As of March 31, 2023 and December 31, 2022, the following fair value hierarchy table presents the Company’s financial assets measured at fair value on a recurring basis (in thousands): Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs As of March 31, 2023 Assets: Cash and cash equivalents: Money market funds $ 8,967 $ 8,967 $ — $ — U.S. Treasury debt securities 1,997 1,997 — — Total cash and cash equivalents $ 10,964 $ 10,964 $ — $ — Short-term investments: U.S. Treasury debt securities $ 36,142 $ 36,142 $ — $ — Commercial Paper 4,952 — 4,952 — U.S. Government Agency 1,979 — 1,979 — Total short-term investments $ 43,073 $ 36,142 $ 6,931 $ — Total assets measured at fair value $ 54,037 $ 47,106 $ 6,931 $ — Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs As of December 31, 2022 Assets: Cash and cash equivalents: Money market funds $ 25,108 $ 25,108 $ — $ — U.S. Treasury debt securities 1,996 1,996 — — U.S. Government Agency 1,991 — 1,991 — Total cash and cash equivalents $ 29,095 $ 27,104 $ 1,991 $ — Short-term investments: U.S. Treasury debt securities $ 21,688 $ 21,688 $ — $ — Commercial Paper 2,936 — 2,936 — U.S. Government Agency 1,958 — 1,958 — Total short-term investments $ 26,582 $ 21,688 $ 4,894 $ — Total assets measured at fair value $ 55,677 $ 48,792 $ 6,885 $ —

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2023
Summary of Warrant Activity and Changes in Warrants Outstanding	A summary of warrant activity and changes in warrants outstanding is presented below: Number of Shares Underlying Warrants Weighted-Average Exercise Price Per Share Weighted-Average Remaining Contractual Term (in years) Balance at December 31, 2022 3,410,642 $ 3.70 2.94 Issued — $ — — Forfeited — $ — — Exercised — $ — — Balance at March 31, 2023 3,410,642 $ 3.70 2.69
Summary of Stock Option Activity	A summary of the Company’s stock option activity under the 2015 Plan, 2019 Plan and Inducement Plan is as follows: Number of Options Weighted-Average Exercise Price Weighted-Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Outstanding at December 31, 2022 8,515,696 $ 4.16 8.1 $ 101,611 Granted 2,654,000 $ 0.97 Forfeited ( 184,347 ) $ 3.72 Outstanding at March 31, 2023 10,985,349 $ 3.40 7.5 $ 13,254 Options vested and expected to vest as of March 31, 2023 10,985,349 $ 3.40 7.5 $ 13,254 Options vested and exercisable as of March 31, 2023 4,349,256 $ 4.51 6.8 $ 13,254
Summary of Restricted Stock Unit Activity	Restricted stock unit activity under Equity Incentive Plans is summarized as follows: Number of Restricted Stock Units Weighted-Average Remaining Contractual Term (in years) Weighted-Average Grant Date Fair Value Nonvested at December 31, 2022 1,009,083 0.6 $ 1.64 Granted — Vested ( 217,676 ) $ 2.43 Forfeited/ Repurchased ( 38,432 ) $ 1.27 Nonvested at March 31, 2023 752,975 0.5 $ 1.43 Units expected to vest as of March 31, 2023 747,456 0.5 $ 1.42
Schedule of Assumptions Used to Determine Fair Value	The weighted-average assumptions used in the Black-Scholes option pricing model to determine the fair value of stock option grants, were as follows: Three Months Ended March 31, 2023 2022 Risk-free interest rate 4.1 % 1.7 % Expected volatility 99.8 % 100.4 % Expected term (in years) 6.1 6.2 Expected dividend yield — % — %
Summary of Share-Based Compensation Expense	Stock-based compensation expense recognized for all equity awards has been reported in the condensed consolidated statements of operations as follows (in thousands): Three Months Ended March 31, 2023 2022 Research and development $ 1,117 $ 1,063 General and administrative 768 915 $ 1,885 $ 1,978
Common Stock Reserved for Future Issuance	Common stock reserved for future issuance is as follows (in thousands): March 31, Common stock warrants 3,411 Common stock options issued and outstanding 10,985 Restricted stock unit awards unvested and outstanding 753 Common stock available for issuance under the Inducement Plan and 2019 Plan 1,758 16,907

Description of Business, Basi_4

Description of Business, Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 04, 2023	Mar. 31, 2023	Dec. 31, 2022
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit		$ (169,787)	$ (158,300)
Cash, cash equivalents, and short-term investments		$ 54,300
Subsequent Event
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Common stock transaction price per share	$ 1
Common Stock
Description Of Business Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Common stock transaction price per share		$ 1

Description of Business, Basi_5

Description of Business, Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss per Share Would Be Anti-dilutive (Detail) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities	15,149,000	12,898,000
Warrants to purchase common stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities	3,411,000	4,235,000
Common Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities	10,985,000	8,199,000
Restricted Stock Unit
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities	753,000	464,000

Balance Sheet Details - Prepaid

Balance Sheet Details - Prepaid and Other (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Prepaid Expense, Current [Abstract]
Research and development	$ 15	$ 0
Clinical trials	2,845	2,616
Insurance	321	669
Other prepaid expenses	137	103
Other receivable	282	178
Prepaid and other expense total	$ 3,600	$ 3,566

Balance Sheet Details - Accrued

Balance Sheet Details - Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Research and development	$ 850	$ 972
Clinical Trials	1,284	868
Legal fees	128	138
Compensation	1,110	2,691
Other	102	9
Total accrued liabilities	$ 3,474	$ 4,678

Marketable Securities - Schedul

Marketable Securities - Schedule of Short-term Investments and are Measured at a Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 54,026	$ 55,668
Unrealized Gains	11	9
Unrealized Losses	0	0
Available-for-sale debt securities	54,037	55,677
Cash and cash equivalents
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	10,964	29,095
Unrealized Gains	0	0
Unrealized Losses	0	0
Available-for-sale debt securities	10,964	29,095
Short term investments
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	43,062	26,573
Unrealized Gains	11	9
Unrealized Losses	0	0
Available-for-sale debt securities	43,073	26,582
Money market funds | Cash and cash equivalents
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	8,967	25,108
Unrealized Gains	0	0
Unrealized Losses	0	0
Available-for-sale debt securities	$ 8,967	$ 25,108
Money market funds | Cash and cash equivalents | Maximum
Debt Securities, Available-for-Sale [Line Items]
Maturity (in years)	1 year	1 year
U.S. Treasury debt securities | Cash and cash equivalents
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 1,997	$ 1,996
Unrealized Gains	0	0
Unrealized Losses	0	0
Available-for-sale debt securities	$ 1,997	$ 1,996
U.S. Treasury debt securities | Cash and cash equivalents | Maximum
Debt Securities, Available-for-Sale [Line Items]
Maturity (in years)	1 year	1 year
U.S. Treasury debt securities | Short term investments
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 36,131	$ 21,681
Unrealized Gains	11	7
Unrealized Losses	0	0
Available-for-sale debt securities	$ 36,142	$ 21,688
U.S. Treasury debt securities | Short term investments | Maximum
Debt Securities, Available-for-Sale [Line Items]
Maturity (in years)	1 year	1 year
Commercial Paper | Short term investments
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 4,952	$ 2,936
Unrealized Gains	0	0
Unrealized Losses	0	0
Available-for-sale debt securities	$ 4,952	$ 2,936
Commercial Paper | Short term investments | Maximum
Debt Securities, Available-for-Sale [Line Items]
Maturity (in years)	1 year	1 year
U.S. Government Agency | Cash and cash equivalents
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost		$ 1,991
Unrealized Gains		0
Unrealized Losses		0
Available-for-sale debt securities		$ 1,991
U.S. Government Agency | Cash and cash equivalents | Maximum
Debt Securities, Available-for-Sale [Line Items]
Maturity (in years)		1 year
U.S. Government Agency | Short term investments
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 1,979	$ 1,956
Unrealized Gains	0	2
Unrealized Losses	0	0
Available-for-sale debt securities	$ 1,979	$ 1,958
U.S. Government Agency | Short term investments | Maximum
Debt Securities, Available-for-Sale [Line Items]
Maturity (in years)	1 year	1 year

Marketable Securities - Additio

Marketable Securities - Additional Information (Details)	3 Months Ended
	Mar. 31, 2023 USD ($)
Investments, Debt and Equity Securities [Abstract]
Available for sale securities impairment loss	$ 0
Marketable securities credit losses	$ 0

Commitments, Contingencies an_2

Commitments, Contingencies and Related Party Transactions - Additional Information (Details) - San Diego, California - Office Space - USD ($) $ in Thousands		3 Months Ended
	Apr. 18, 2022	Mar. 31, 2023	Mar. 31, 2022
Commitments And Contingencies [Line Items]
Rent expense		$ 39,000	$ 46,000
Annual base rent	$ 157,000
Lease discount rate		10%
Operating lease liability		$ 50,000
Weighted average remaining lease term		3 months 18 days

License, Collaboration and Gr_2

License, Collaboration and Grant Award/ Subaward Agreements - Additional Information (Details) - USD ($) shares in Millions		1 Months Ended				3 Months Ended		12 Months Ended
	Nov. 01, 2021	Jan. 31, 2022	Aug. 31, 2021	Aug. 31, 2017	May 31, 2016	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2017	Dec. 31, 2015	Sep. 30, 2021	Dec. 31, 2014
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Patent costs as general and administrative expense						$ 3,315,000	$ 3,679,000
Grant revenue						203,000	746,000
The National Institute of Health ("NIH") Grant Awards
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Grants awarded to researchers			$ 2,200,000			1,800,000
Grant revenue						100,000	100,000
Payable to subawardees			$ 700,000			300,000
Award payments received						200,000	500,000
Unbilled grant receivable						100,000
Georgetown University
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Annual license maintenance fee to be paid and payment made									$ 10,000,000
MD Anderson Cancer Center
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development expense						$ 0	100,000
Aggregate cost										$ 800,000
Regents of the University of California
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Written notice of termination, period						60 years
Research and development expense						$ 5,000,000	25,000,000
Upfront license fees paid					$ 500,000
Common stock shares issued					107,108
Annual license maintenance fees								$ 25,000,000
Worldwide sales milestones based on achievement of tiered revenue levels					$ 75,000,000
University of California San Diego School of Medicine | The California Institute for Regenerative Medicine ("CIRM") Award
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Grants awarded to researchers				$ 18,300,000
Development milestones to be received under research sub award agreements throughout award project period				$ 14,500,000
Subaward payments received							0
Exclusive License Agreement | Georgetown University
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Written notice of termination, period						90 days
Days after receipt of notice, to pay failure amount						30 days
Days after receipt of notice for default in payment						60 days
Minimum period in days of written notice to terminate license agreement						60 days
Collaborative Arrangement | MD Anderson Cancer Center
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential regulatory milestone payments											$ 1,000,000
Research Agreement 2022 | Regents of the University of California | The National Institute of Health ("NIH") Grant Awards
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research agreement term		4 years
Research amount received		$ 1,600,000
Research amount payable quarterly		125,000,000
Other Research and Development Expense						$ 100,000	100,000
Research Agreement 2023 | Regents of the University of California | The National Institute of Health ("NIH") Grant Awards
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research amount payable quarterly		131,250,000
Research Agreement 2024 | Regents of the University of California | The National Institute of Health ("NIH") Grant Awards
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research amount payable quarterly		$ 137,813,000
License Agreement | University of Tennessee Research Foundation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research and development expense						$ 200,000	$ 200,000
CVR Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Period Which Payment Of Percentage Of Net Proceeds Would Be Payable Under C V R	15 years
Period Which Grant Sale Or Transfer Of Rights To Company Sard Or Sarm Technology Could Trigger Payment Under Cvr Agreement	10 years
Percentage Of NetSales	5%
Maximum | Regents of the University of California
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential regulatory milestone payments					24,500,000
Maximum | Exclusive License Agreement | Georgetown University
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential milestone payments									$ 200,000
Minimum | Regents of the University of California
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential regulatory milestone payments					20,100,000
Advance licensed assets					$ 1,000,000

Fair Value - Schedule of Compan

Fair Value - Schedule of Companys Assets Measured at Fair Value on Recurring Basis (Details) - Fair Value Measurements Recurring - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	$ 10,964	$ 29,095
Total short-term investments	43,073	26,582
Total assets measured at fair value	54,037	55,677
U.S. Government Agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents		1,991
Total short-term investments	1,979	1,958
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	8,967	25,108
U.S. Treasury debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	1,997	1,996
Total short-term investments	36,142	21,688
Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	4,952	2,936
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	10,964	27,104
Total short-term investments	36,142	21,688
Total assets measured at fair value	47,106	48,792
Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Government Agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents		0
Total short-term investments	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	8,967	25,108
Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	1,997	1,996
Total short-term investments	36,142	21,688
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	0	1,991
Total short-term investments	6,931	4,894
Total assets measured at fair value	6,931	6,885
Significant Other Observable Inputs (Level 2) | U.S. Government Agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents		1,991
Total short-term investments	1,979	1,958
Significant Other Observable Inputs (Level 2) | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	0	0
Significant Other Observable Inputs (Level 2) | U.S. Treasury debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	0	0
Total short-term investments	0	0
Significant Other Observable Inputs (Level 2) | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	4,952	2,936
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	0	0
Total short-term investments	0	0
Total assets measured at fair value	0	0
Significant Unobservable Inputs (Level 3) | U.S. Government Agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents		0
Total short-term investments	0	0
Significant Unobservable Inputs (Level 3) | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	0	0
Significant Unobservable Inputs (Level 3) | U.S. Treasury debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	0	0
Total short-term investments	0	0
Significant Unobservable Inputs (Level 3) | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	$ 0	$ 0

Fair Value - Additional informa

Fair Value - Additional information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers into or out of Level 3	$ 0	$ 0

Stockholders' Equity - Summary

Stockholders' Equity - Summary Of Warrant Activity And Changes In Warrants Outstanding (Details) - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Equity [Abstract]
Options outstanding, Number of Warrant Beginning	3,410,642
Number of Shares Underlying Warrants Forfeited	0
Number of Shares Underlying Warrants Exercised	0
Options outstanding, Number of Warrant Ending	3,410,642	3,410,642
Weighted-Average Exercise Price Beginning	$ 3.70
Forfeited Weighted Average Exercise Price	0
Exercised Weighted Average Exercise Price	$ 0
Weighted-Average Exercise Price Ending	$ 3.70	$ 3.70
Weighted-Average Remaining Contractual Term	2 years 8 months 8 days	2 years 11 months 8 days

Stockholders' Equity - ATM Prog

Stockholders' Equity - ATM Program (Details) - ATM Program - Common Stock - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Dec. 31, 2021	Mar. 31, 2023
Subsidiary, Sale of Stock [Line Items]
Number of shares sold		1,115,480
Net proceeds from sale of shares		$ 1.2
Aggregate offering price	$ 50

Stockholders' Equity - Equity I

Stockholders' Equity - Equity Incentive Plans (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
	Jul. 31, 2015	Mar. 31, 2023	Mar. 31, 2022	May 25, 2021
Class Of Stock [Line Items]
Percentage of annual increase in shares reserved for issuance		5%
Number of common stock shares provided for issuance of stock awards to its employees		16,907,000
Restricted Stock Unit
Class Of Stock [Line Items]
Fair value of RSUs vested		$ 0.2
2019 incentive award plan
Class Of Stock [Line Items]
Shares of common stock reserved for issuance		1,954,150
2019 incentive award plan and inducement plan
Class Of Stock [Line Items]
Number of common stock shares provided for issuance of stock awards to its employees				2,800,000
2015 plan
Class Of Stock [Line Items]
Options expiration term	10 years
Options vesting period	4 years
2019 Plan And Inducement Plan
Class Of Stock [Line Items]
Number of common stock shares provided for issuance of stock awards to its employees		1,757,954,000
2019 plan
Class Of Stock [Line Items]
Options expiration term	10 years
Options vesting period	4 years
2019 and 2015 plan
Class Of Stock [Line Items]
Weighted average grant date fair value per share of option grants		$ 0.78	$ 1.54

Stockholders' Equity - Summar_2

Stockholders' Equity - Summary of Stock Option Activity (Details) - Equity incentive plan - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of options, beginning balance	8,515,696
Number of options, granted	2,654,000
Number of options,forfeited	(184,347)
Number of options, ending balance	10,985,349	8,515,696
Number of restricted units expected to vest	10,985,349
Number of options, vested and exercisable	4,349,256
Weighted average exercise price, beginning balance	$ 4.16
Weighted average exercise price, granted	0.97
Weighted average exercise price, forfeited	3.72
Weighted average exercise price, ending balance	3.40	$ 4.16
Weighted average exercise price, options vested and expected to vest	3.40
Weighted average exercise price, options vested and exercisable	$ 4.51
Weighted average contractual term outstanding, begining balance	7 years 6 months	8 years 1 month 6 days
Weighted average contractual term outstanding, ending balance	7 years 6 months	8 years 1 month 6 days
Weighted average remaining contractual term, options vested and expected to vest	7 years 6 months
Weighted average remaining contractual term, options vested and exercisable	6 years 9 months 18 days
Aggregate intrinsic value beginning balance	$ 101,611
Aggregate intrinsic value ending balance	13,254	$ 101,611
Aggregate intrinsic value, options vested and expected to vest	13,254
Aggregate intrinsic value, options vested and exercisable	$ 13,254

Stockholders Equity - Summary o

Stockholders Equity - Summary of Restricted Stock Unit Activity (Details) - Restricted Stock Unit - $ / shares shares in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of restricted stock units, Beginning balance	1,009,083
Number of restricted stock units, Granted	0
Number of restricted stock units, Vested	(217,676)
Number of restricted stock units, Forfeited/Repurchased	(38,432)
Number of restricted stock units, Ending balance	752,975	1,009,083
Number of restricted units expected to vest	747,456
Weighted-average remaining contractual term nonvested	6 months	7 months 6 days
Weighted-average remaining contractual term units expected to vest	6 months
Weighted-average grant date fair value nonvested	$ 1.64
Weighted-average grant date fair value, vested	2.43
Weighted-average grant date Fair Value, forfeited/ repurchased	1.27
Weighted-average grant date fair value nonvested	1.43	$ 1.64
Weighted average exercise price, options vested and expected to vest	$ 1.42

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Assumptions Used to Estimate Fair Value of Stock Option Grants (Details)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Share-Based Payment Arrangement [Abstract]
Risk-free interest rate	4.10%	1.70%
Expected volatility	99.80%	100.40%
Expected term (in years)	6 years 1 month 6 days	6 years 2 months 12 days

Stockholders' Equity - Share-Ba

Stockholders' Equity - Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,885	$ 1,978
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	1,117	1,063
General and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 768	$ 915

Stockholders' Equity - Stock-Ba

Stockholders' Equity - Stock-Based Compensation Expense (Details) $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock option	$ 12.5
Remaining weighted-average period	3 years
Restricted Stock Unit
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock option	$ 0.7
Remaining weighted-average period	9 months 18 days

Stockholders' Equity - Common S

Stockholders' Equity - Common Stock Reserved for Future Issuance (Details) shares in Thousands	Mar. 31, 2023 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock warrants	3,411
Common stock options issued and outstanding	10,985
Restricted stock unit awards	753
Common stock available for issuance under the Inducement Plan and 2019 Plan	16,907
Equity incentive plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock available for issuance under the Inducement Plan and 2019 Plan	1,758