Forte Biosciences (FBRX) 10-K 18 Mar 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Mar. 11, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Entity Interactive Data Current	Yes
Trading Symbol	FBRX
Entity Current Reporting Status	Yes
Entity Registrant Name	FORTE BIOSCIENCES, INC.
Entity Central Index Key	0001419041
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Shell Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Small Business	true
Entity Emerging Growth Company	false
Title of 12(b) Security	Common Stock
Security Exchange Name	NASDAQ
Entity File Number	001-38052
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-1243872
Entity Address, Address Line One	3060 Pegasus Park Drive, Building 6
Entity Address, City or Town	Dallas
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75247
City Area Code	310
Local Phone Number	618-6994
Document Annual Report	true
Document Transition Report	false
Entity Public Float			$ 20.4
Entity Common Stock, Shares Outstanding		36,394,882
Auditor Name	KPMG LLP
Auditor Firm ID	185
Auditor Location	San Diego, California
Documents Incorporated by Reference	Portions of the Registrant’s definitive proxy statement to be filed with the Securities and Exchange Commission, or SEC, subsequent to the date hereof pursuant to Regulation 14A in connection with the Registrant’s 2024 Annual Meeting of Stockholders will be incorporated by reference into Part III of this Annual Report on Form 10-K assuming such proxy statement is filed with the SEC not later than 120 days after the conclusion of the registrant’s fiscal year ended December 31, 2023. If such proxy statement is not filed on or before such date, the information called for by Part III will be filed as part of an amendment to this Annual Report on Form 10-K on or before such date.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 37,125	$ 41,100
Prepaid expenses and other current assets	1,202	411
Total current assets	38,327	41,511
Property and equipment, net	109
Other assets	544	486
Total assets	38,980	41,997
Current liabilities:
Accounts payable	1,424	1,153
Accrued liabilities	2,242	2,026
Total current liabilities	3,666	3,179
Commitments and contingencies (Note 5)
Stockholders’ equity
Common stock, $0.001 par value: 200,000,000 shares authorized as of December 31, 2023 and December 31, 2022; 36,335,105 and 21,000,069 shares issued and outstanding at December 31, 2023 and December 31, 2022, respectively	36	21
Additional paid-in capital	153,794	125,841
Accumulated other comprehensive income	4
Accumulated deficit	(118,520)	(87,044)
Total stockholders’ equity	35,314	38,818
Total liabilities and stockholders' equity	$ 38,980	$ 41,997

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	36,335,105	21,000,069
Common stock, shares outstanding	36,335,105	21,000,069

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating expenses:
Research and development	$ 21,862	$ 5,594
General and administrative	10,624	8,302
Total operating expenses	32,486	13,896
Loss from operations	(32,486)	(13,896)
Interest income	1,124	162
Other expense, net	(114)	(145)
Net loss	$ (31,476)	$ (13,879)
Net loss per share - basic	$ (1)	$ (0.8)
Net loss per share - diluted	$ (1)	$ (0.8)
Weighted average shares and pre-funded warrants outstanding, basic	31,571,039	17,383,531
Weighted average shares and pre-funded warrants outstanding, diluted	31,571,039	17,383,531
Comprehensive Loss:
Net loss	$ (31,476)	$ (13,879)
Unrealized gain on available-for-sale securities	4
Comprehensive loss	$ (31,472)	$ (13,879)

Consolidated Statements of Conv

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning balance at Dec. 31, 2021	$ 41,548	$ 15	$ 114,698		$ (73,165)
Beginning balance, shares at Dec. 31, 2021		14,754,447
Exercise of employee stock options	1		1
Exercise of employee stock options, shares		1,098
Issuance of common stock under ESPP	11		11
Issuance of common stock under ESPP, shares		5,716
Issuance of common stock through public equity offering, net of offering costs of $595	7,122	$ 6	7,116
Issuance of common stock through public equity offering, net of offering costs of $595, shares		6,142,158
Issuance of common stock upon vesting of restricted stock units, net, shares		96,650
Stock-based compensation	4,015		4,015
Net loss	(13,879)				(13,879)
Ending Balance at Dec. 31, 2022	38,818	$ 21	125,841		(87,044)
Ending balance, shares at Dec. 31, 2022		21,000,069
Issuance of common stock under ESPP	16		16
Issuance of common stock under ESPP, shares		17,500
Issuance of common stock and pre-funded warrants in PIPE financing, net of issuance costs of $272	24,728	$ 15	24,713
Issuance of common stock and pre-funded warrants in PIPE financing, net of issuance costs of $272, Shares		15,166,957
Issuance of common stock upon vesting of restricted stock units, net, shares		150,579
Issuance of common stock upon vesting of restricted stock units, value	(60)		(60)
Stock-based compensation	3,284		3,284
Unrealized gain on available-for-sale securities	4			$ 4
Net loss	(31,476)				(31,476)
Ending Balance at Dec. 31, 2023	$ 35,314	$ 36	$ 153,794	$ 4	$ (118,520)
Ending balance, shares at Dec. 31, 2023		36,335,105

Consolidated Statements of Co_2

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Statement of Stockholders' Equity [Abstract]
Offering costs		$ 595
Issuance costs	$ 272

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (31,476)	$ (13,879)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	9
Accretion of debt discount on available-for-sale securities	(131)
Stock based compensation expense	3,284	4,015
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(849)	258
Accounts payable	271	207
Accrued liabilities	186	1,214
Net cash used in operating activities	(28,706)	(8,185)
Cash flows from investing activities:
Purchase of available-for-sale securities	(9,965)
Proceeds from maturity of available-for-sale securities	10,100
Purchase of property and equipment	(88)
Net cash provided by investing activities	47
Cash flows from financing activities:
Proceeds from issuance of common stock and pre-funded warrants, net of issuance costs	24,728	7,229
Proceeds from exercise of employee stock options and issuance of common stock under ESPP	16	12
Taxes paid related to net share settlement of equity awards	(60)
Net cash provided by financing activities	24,684	7,241
Net decrease in cash and cash equivalents	(3,975)	(944)
Cash and cash equivalents - beginning of year	41,100	42,044
Cash and cash equivalents - end of year	37,125	$ 41,100
Supplemental disclosure of non-cash investing and financing activities
Purchase of fixed assets recorded in accrued expenses	$ 30

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (31,476)	$ (13,879)

Insider Trading Arrangements

Insider Trading Arrangements	12 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Organization and Description of

Organization and Description of Business	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	1. Organization and Description of Business Forte Biosciences, Inc. (www.fortebiorx.com) and its subsidiaries, referred to herein as the “Company” or "Forte", is a clinical- stage biopharmaceutical company focused on developing its FB-102 program which the Company believes has potentially broad applications for autoimmune and autoimmune-related diseases, including graft-versus-host disease ("GvHD"). FB-102 is currently in a Phase 1 clinical trial. The Company merged with Tocagen, Inc. ("Merger"), a publicly traded biotechnology company, on June 15, 2020. Prior to the Merger, Forte was a privately held company incorporated in Delaware on May 3, 2017. The Company's headquarters is in Dallas, Texas. The Company’s common stock is traded on the Nasdaq stock exchange under the ticker symbol “FBRX”‌. Liquidity and Risks The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern, which contemplates the realization of assets and the settlement of liabilities and commitments in the normal course of business. The consolidated financial statements do not reflect any adjustments relating to the recoverability and reclassification of assets and liabilities that might be necessary if the Company is unable to continue as a going concern. Since inception, the Company has incurred losses and negative cash flows from operations. As of December 31, 2023, the Company had an accumulated deficit of $ 118.5 million . The Company used $ 28.7 million of cash in operating activities during the year ended December 31, 2023. Management expects to continue to incur additional losses in the foreseeable future as the Company focuses its development efforts on advancing FB-102 through clinical trials. From its inception through December 31, 2023, the Company’s financial support has primarily been provided from the sale of its common stock and from the Merger. The Company had cash and cash equivalents of approximately $ 37.1 million as of December 31, 2023. The Company’s cash and cash equivalents are held at financial institutions and exceed federally insured limits. The Company believes that its existing cash and cash equivalents will be sufficient to allow the Company to fund its operations for at least 12 months from the filing date of this Form 10-K. The Company will continue to need to raise additional capital or obtain financing from other sources. Management may fund future operations through the sale of equity and debt financings and may also seek additional capital through arrangements with strategic partners or other sources. There can be no assurance that additional funding will be available on terms acceptable to the Company, if at all. If the Company is unable to raise additional funding to meet its working capital needs in the future, it may be forced to delay or reduce the scope of its research and development programs and/or limit or cease its operations. The Company's ability to raise additional funds may be adversely impacted by potential worsening global economic conditions and the recent disruptions to, and volatility in, the credit and financial markets in the United States and worldwide resulting from the military conflicts in Eastern Europe, the Middle East, and otherwise. There are numerous risks and uncertainties associated with pharmaceutical development and the Company is unable to predict the timing or amount of increased expenses on the development of future product candidates or when or if it will start to generate revenues. Even if the Company does generate revenues, it may not be able to achieve or maintain profitability. If the Company fails to become profitable or is unable to sustain profitability on a continuing basis, then it may be unable to continue its operations at planned levels and may be forced to reduce its operations. Businesses throughout our industry have been and will continue to be impacted by a number of challenging and unexpected global and national events and circumstances that continue to evolve, including without limitation the COVID-19 pandemic, the military conflicts in Ukraine and the Middle East, increased economic uncertainty, inflation, rising interest rates, recent and any potential future financial institution failures, and other geopolitical tensions. The extent of the impact of these events and circumstances on our business, operations, development timelines and plans remains uncertain, and will depend on certain developments, including the duration and scope of the events and their impact on the Company's development activities, third parties with whom it does business, as well as its impact on regulatory authorities and its key scientific and management personnel. The Company has been and continues to actively monitor the potential impacts that these various events and circumstances may have on its business and the Company takes steps, where warranted, to minimize any potential negative impacts on its business resulting from these events and circumstances.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The Company prepares its consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“GAAP”), as found in the Accounting Standards Codification (“ASC”), the Accounting Standards Update (“ASU”), of the Financial Accounting Standards Board (“FASB”), and the rules and regulations of the US Securities and Exchange Commission (“SEC”). Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries, Forte Subsidiary, Inc. Forte Biosciences Emerald Limited and Forte Biosciences Australia Proprietary Limited. All intercompany accounts and transactions have been eliminated in the preparation of the consolidated financial statements. Use of Estimates The preparation of the Company’s consolidated financial statements requires management to make estimates and assumptions that impact the reported amounts of assets, liabilities, expenses and the disclosure of contingent assets and liabilities in the Company’s consolidated financial statements and accompanying notes. Significant management estimates that affect the reported amounts of assets, liabilities and expenses include stock-based compensation expense and accruals for clinical trials and drug manufacturing. 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. Segment Information The Company operates as a single operating segment. The Company’s chief operating decision maker, its Chief Executive Officer, manages the Company’s operations on a consolidated basis for the purposes of allocating resources, making operating decisions and evaluating financial performance. Cash and cash equivalents Cash and cash equivalents include U.S. Treasury bills, money market funds and deposits with commercial banks. Cash equivalents are defined as short-term, highly liquid investments with original maturities of 90 days or less at the date of purchase. Available-for-Sale Securities The Company’s available-for-sale securities primarily consist of U.S. government and agency securities. Securities with maturities from the date of purchase of less than three months are included in cash equivalents. The Company classifies its marketable securities as available-for-sale and records such assets at estimated fair value in the consolidated balance sheets, with unrealized gains and losses, if any, reported as a component of other comprehensive income (loss) within the consolidated statements of operations and comprehensive loss and as a separate component of stockholders’ equity. Realized gains and losses are calculated on the specific identification method and recorded as interest income (loss). Any premium arising at purchase is amortized to the earliest call date and any discount arising at purchase is accreted to maturity. Accretion of discounts are recorded in interest income in the consolidated statements of operations and comprehensive loss. Fair Value of Financial Instruments Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There is a three-level hierarchy that prioritizes the inputs used in determining fair value by their reliability and preferred use as follows: • Level 1 - Valuations based on quoted prices in active markets for identical assets or liabilities. • Level 2 – Valuations based on quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data. • Level 3 – Valuations based on inputs that are both significant to the fair value measurements and are unobservable. To the extent that a valuation is based on models or inputs that are less observable, or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized within Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. There have been no significant changes to the valuation methods utilized by the Company during the periods presented. There have been no transfers between Level 1, Level 2, and Level 3 in any periods presented. The carrying amounts of financial instruments consisting of cash and cash equivalents, accounts payable, accrued liabilities included in the Company’s financial statements are reasonable estimates of fair value, primarily due to their short maturities. Property and Equipment, Net Property and equipment are stated at cost less accumulated depreciation, subject to review for impairment. Property and equipment, net are depreciated over the estimated useful lives of the assets, generally three to five years , using the straight-line method. Impairment of Property and Equipment The Company reviews its property and equipment for impairment when events or changes in circumstances indicate the carrying value of the assets may not be recoverable. Recoverability is measured by comparing the book values of the assets to future net undiscounted cash flows that the assets or the asset groups are expected to generate. If such assets are considered impaired, the impairment to be recognized is measured by the amount the book value of the assets exceed their fair value, which is measured based on the estimated discounted future net cash flows arising from the assets or asset groups. No impairment losses on property and equipment have been recorded for the year ended December 31, 2023 or 2022. Pre-Funded Warrants Pre-funded warrants are accounted for as either derivative liabilities or as equity instruments depending on the specific terms of the agreement. The pre-funded warrants are equity-classified instruments that were recorded in additional paid-in capital at issuance and are not subject to remeasurement. The Company periodically evaluates changes in facts and circumstances that could impact the classification of warrants. Research and Development Costs Research and development costs are expensed as incurred. Research and development costs consist primarily of salaries and benefits of research and development personnel, costs related to research activities, preclinical studies, clinical trials and drug manufacturing. Non-refundable advance payments for goods or services that will be used in future research and development activities are deferred and capitalized and are only expensed when the goods have been received or when the service has been performed rather than when the payment is made. Drug manufacturing and clinical trial costs are a component of research and development expenses. The Company expenses costs for its drug manufacturing activities performed by Contract Manufacturing Organizations (“CMOs”), preclinical and clinical trial costs performed by Contract Research Organizations (“CROs”) and other service providers, as they are incurred, based upon estimates of the work completed over the life of the individual study in accordance with associated agreements. The Company uses information it receives from internal personnel and outside service providers to estimate the percentage of completion and therefore the expense to be incurred. Patent Costs Costs related to filing and pursuing patent applications, including direct application fees and the legal and consulting expenses related to making such applications, are expensed as incurred, as recoverability of such expenditures is uncertain. These costs are included in general and administrative expenses within the consolidated statements of operations and comprehensive loss. Comprehensive Los s Comprehensive loss is defined as the change in equity during a period from transactions from non-owner sources. Other comprehensive loss includes unrealized gains on available-for-sale securities, which was the only difference between net loss and comprehensive loss for the applicable periods. Net Loss Per Share The Company’s net loss is equivalent to net loss attributable to common stockholders for all periods presented. Basic net loss per share is computed by dividing net loss applicable to common stockholders by the weighted average number of common shares, without consideration for common stock equivalents. The weighted average number of shares of common stock used in the basic and diluted net loss per share calculation include the pre-funded warrants outstanding during the period as they are exercisable at any time and their exercise requires only nominal consideration for the delivery of shares. As of December 31, 2023, no pre-funded warrants have been exercised and there were pre-funded warrants to purchase an aggregate of 9,689,293 shares of common stock outstanding. Diluted net loss per share is computed by dividing net loss by the weighted-average number of shares of common stock and common stock equivalents outstanding during the period in accordance with the treasury stock method. The following number of unexercised stock options, restricted stock units, warrants, and shares expected to be purchased under the ESPP, which are common stock equivalents, have been excluded from the diluted net loss calculation as their effect would have been anti-dilutive for the periods presented: Year Ended December 31, 2023 2022 Options 2,645,278 2,363,195 Restricted stock units 1,055,951 162,201 Warrants 4,434 4,434 ESPP 1,847 — Total 3,707,510 2,529,830 Stock-Based Compensation The Company issues stock-based awards to employees, directors and non-employees, generally in the form of stock options, restricted stock units or rights granted to employees under the Employee Stock Purchase Plan (“ESPP”). The Company accounts for stock-based compensation awards in accordance with ASC Topic 718, Compensation—Stock Compensation . The Company measures compensation cost for all equity awards for employees, directors and non-employees at their grant-date fair value and recognizes compensation expense for service-based awards on a straight-line basis over the requisite service period, which is generally the vesting period. The grant-date fair value of stock options is estimated using the Black-Scholes option pricing model. The grant-date fair value of restricted stock units is determined using the Company’s closing stock price on the date of grant. Forfeitures are recognized as they occur. Stock-based compensation expense for an award with a performance condition is recognized when the achievement of the performance condition has been determined to be probable. If the outcome of such performance condition has not been determined to be probable, or has not been met, no compensation expense is recognized and any previously recognized compensation expense is reversed. For rights granted under the ESPP, the fair value of each purchase is estimated at the beginning of the offering period using the Black-Scholes option pricing model. The Company classifies stock-based compensation expense in its statement of operations in the same manner in which the award recipient’s salary and related costs are classified in the case of employees, or in which the award recipient’s service payments are classified in the case of directors and non-employees. Foreign Currency Transactions Transaction gains and losses that arise from exchange rate fluctuations on transactions denominated in currencies other than the US dollar are recorded to other expenses, net in the consolidated statements of operations and comprehensive loss and were not material for the periods presented. The Company's subsidiaries use the U.S. dollar as their functional currency. Income Taxes The Company uses an asset and liability approach to account for income taxes. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax bases of assets and liabilities. These differences are measured using the enacted statutory tax rates that are expected to be in effect for the years in which differences are expected to reverse. Valuation allowances are provided when the expected realization of deferred tax assets does not meet a “more likely than not” criterion. The Company makes estimates and judgments about its future taxable income that are based on assumptions that are consistent with its plans and estimates. Should the actual amounts differ from those estimates, the amount of the valuation allowance could be materially impacted. Changes in these estimates may result in significant increases or decreases to the Company’s tax provision in a period in which such estimates are changed, which in turn would affect net income or loss. The Company recognizes tax benefits from uncertain tax positions if it believes the position is more likely than not to be sustained on examination by the taxing authorities based on the technical merits of the position. The Company makes adjustments to these reserves when facts and circumstances change, such as the closing of a tax audit or the refinement of an estimate. The provision for income taxes includes the effects of any reserves for tax positions that are not more likely than not to be sustained, as well as the related net interest and penalties. Recently Issued Accounting Standards Not Yet Adopted From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and are adopted by the Company as of a specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on the Company’s financial position or results of operations. In August 2020, the FASB issued ​ASU 2020-06​, ​Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in an Entity’s Own Equity (Subtopic 815-40)​ (“ASU 2020-06”). ​ASU 2020-06 eliminates the beneficial conversion and cash conversion accounting models for convertible instruments. It also amends the accounting for certain contracts in an entity’s own equity that are currently accounted for as derivatives because of specific settlement provisions. In addition, ASU 2020-06 modifies how particular convertible instruments and certain contracts that may be settled in cash or shares impact the diluted earnings per share computation. The amendments in ASU 2020-06 are effective for smaller reporting companies as defined by the SEC for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early adoption is permitted, but not earlier than fiscal years beginning after December 15, 2020. The Company is currently evaluating the impact of ASU 2020-06 on its consolidated financial statements and does not expect the adoption of this amended guidance to have a material impact on the Company’s consolidated financial statements.

Balance Sheet Components

Balance Sheet Components	12 Months Ended
	Dec. 31, 2023
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Components	3. Balance Sheet Components Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets as of December 31, 2023 and 2022 consist of the following (in thousands): December 31, 2023 December 31, 2022 Prepaid professional fees $ 413 $ — Prepaid insurance 318 341 Prepaid manufacturing & research expense 306 — Other 165 70 Total Prepaid Expenses and Other Current Assets $ 1,202 $ 411 Property and Equipment, Net Property and equipment, net as of December 31, 2023 and 2022 consist of the following (in thousands): December 31, 2023 December 31, 2022 Equipment $ 100 $ — Furniture and Fixtures 18 — Property and equipment, at cost 118 — Less accumulated depreciation ( 9 ) — Total property and equipment, net $ 109 $ — Other Assets Other assets as of December 31, 2023 and 2022 consist of the following (in thousands): December 31, 2023 December 31, 2022 Prepaid insurance $ 280 $ 473 Prepaid professional fees 211 - Other 53 13 Total Other Assets $ 544 $ 486 Accrued Liabilities Accrued liabilities as of December 31, 2023 and 2022 consist of the following (in thousands): December 31, 2023 December 31, 2022 Accrued manufacturing and clinical expenses $ 1,016 $ 485 Accrued compensation 947 890 Accrued legal and professional fees 276 643 Accrued other expenses 3 8 Total Accrued Liabilities $ 2,242 $ 2,026

Fair Value

Fair Value	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value	4. Fair Value The Company measures its financial assets and liabilities at fair value, which is defined as the exit price, or the amount that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The Company uses the following three-level valuation hierarchy that maximizes the use of observable inputs and minimizes the use of unobservable inputs to value its financial assets and liabilities: • Level 1 - Valuations based on quoted prices in active markets for identical assets or liabilities. • Level 2 – Valuations based on quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data. • Level 3 – Valuations based on inputs that are both significant to the fair value measurements and are unobservable. Money market funds are valued at the closing price reported by the fund sponsor from an actively traded exchange. Money market funds and U.S. Treasury bills were included in cash equivalents in the consolidated balance sheets for the periods presented. The Company obtains the fair value of its Level 2 cash equivalents from third-party pricing services. The pricing services utilize industry standard valuation models whereby all significant inputs, including benchmark yields, reported trades, broker/dealer quotes, issuer spreads, bids, offers, or other market-related data, are observable. The following tables provides a summary of the assets that are measured at fair value on a recurring basis as of December 31, 2023 and December 31, 2022 (in thousands): Fair Value Measurements as of Level 1 Level 2 Level 3 Total Cash equivalents: Money Market Funds $ 5,686 $ — $ — $ 5,686 U.S. Treasury Bills $ — $ 25,164 $ — $ 25,164 Total $ 5,686 $ 25,164 $ — $ 30,850 Fair Value Measurements as of Level 1 Level 2 Level 3 Total Cash equivalents: Money Market Funds $ 5,061 $ — $ — $ 5,061 Total $ 5,061 $ — $ — $ 5,061

Available-for-sale Securities

Available-for-sale Securities	12 Months Ended
	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Available-for-sale Securities	5. Available-for-sale Securities The following table summarizes the Company's available-for-sale securities as of December 31, 2023 (in thousands). There were no available-for-sale securities with an unrealized loss as of December 31, 2023. The Company did no t have available-for-sale securities as of December 31, 2022. December 31, 2023 Unrealized Amortized Cost Gains Losses Estimated Fair Value Cash equivalents U.S. Treasury Bills $ 25,160 $ 4 $ — $ 25,164 Total available-for-sale securities $ 25,160 $ 4 $ — $ 25,164 As of December 31, 2023, the Company classified available-for-sales as cash equivalents in the consolidated balance sheet because the maturity dates were less than three months from the date of the purchase. The following table summarizes available-for-sale securities by maturity as of December 31, 2023 (in thousands): Amortized Cost Estimated Fair Value Due in one year or less $ 25,160 $ 25,164 Due after one year — — Total available-for-sale securities $ 25,160 $ 25,164

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	6. Commitments and Contingencies Concentrations of Credit Risk The Company limits its credit risk associated with its cash and cash equivalents by placing them with financial institutions it believes are highly creditworthy. Bank accounts in the United States are insured by the Federal Deposit Insurance Corporation (“FDIC”) up to $ 250 thousand. The Company’s cash accounts significantly exceed FDIC limits. Indemnifications As permitted under Delaware law, the Company indemnifies its officers, directors, and employees for certain events and occurrences while the officer, employee or director is, or was, serving at the Company’s request in such capacity. As of December 31, 2023, the Company did not have any material indemnification claims that were probable or reasonably possible and consequently has not recorded any related liabilities. Lease Agreement The Company has entered into month-to-month lease agreements for certain office and laboratory space. The lease agreements are cancellable by the Company at any time with a 30-day notice. Total rent expense was $ 129 thousand and $ 19 thousand for the year ended December 31, 2023 and 2022, respectively. Clinical and Preclinical Services The Company has entered into various agreements with third party vendors for preclinical and clinical services. The estimated remaining commitments as of December 31, 2023 under these agreements were approximately $ 451 thousand. The Company entered i nto agreements with a clinical research organization ("CRO") in the fourth quarter of 2023 for Phase 1 clinical trials of FB-101, its product candidate. The Company has agreed to pay third-party costs associated with those agreements. The CRO agreements are subject to termination at any time, with or without cause, by the Company, in which case only costs earned or non-cancellable to date of termination would remain subject to reimbursement. Legal Proceedings Camac Fund L.P. v. Forte Biosciences Inc. , C.A. No. 2022-1075-NAC (Del. Ch.) In November 2022, a stockholder of the Company, Camac Fund LP, filed a complaint in the Delaware Court of Chancery seeking to access certain books and records of the Company pursuant to Section 220 of the Delaware General Corporation Law, as well as to seek attorney fees (the “Books and Records Action”). The Books and Records Action, which is captioned Camac Fund L.P. v. Forte Biosciences Inc., C.A. No. 2022-1075-NAC, remains pending. The Company believes that it has meritorious defenses to the claims asserted in the Books and Records Action and intends to vigorously defend against it. Camac Fund, LP v. Paul A. Wagner, et al. , C.A. No. 2023-0817-MTZ (Del. Ch.) On August 10, 2023 , Camac Fund LP filed a complaint (the “Complaint”), captioned Camac Fund, LP v. Paul A. Wagner, et al., C.A. No. 2023-0817-MTZ, in the Delaware Court of Chancery, against the members of the Company’s Board of Directors (the “Directors”) and entities affiliated with certain of the Company’s investors (the “Investors”) and naming the Company as nominal defendant. The Complaint alleged that the Directors breached their fiduciary duties by causing the Company to enter into a July 31, 2023 private placement (the “Private Placement”), which raised approximately $ 25 million for the Company from the Investors and certain of the Company’s executives and directors, and by scheduling the Company’s 2023 annual meeting of stockholders (the “Annual Meeting”) for more than thirteen months after its 2022 annual meeting. The Complaint also alleged the Investors aided and abetted the alleged breaches of fiduciary duty by the Directors. Plaintiff also filed a motion for preliminary injunction and motion to expedite seeking a hearing on its preliminary injunction motion on an expedited basis. The Complaint and motions sought declarations that the Directors breached their fiduciary duties and that the Investors aided and abetted them, to enjoin defendants from counting votes cast by the Investors’ shares obtained through the private placement at the Annual Meeting or any subsequent director election, and money damages in an unspecified amount. On August 15, 2023, the Company, the Directors, and certain Investors filed oppositions to Plaintiff’s motion to expedite. On August 16, 2023, the Company, the Directors, and certain Investors filed motions to dismiss the Complaint. On August 17, 2023, the Court held a hearing at which it granted the motion to expedite in part but declined to schedule a preliminary injunction hearing prior to the Annual Meeting and determined that Defendants could brief their motions to dismiss and be heard on an expedited schedule. The Court determined that discovery could proceed while the motions to dismiss are pending and directed the parties to confer regarding a schedule for further proceedings. On September 1, 2023, Plaintiff voluntarily dismissed its claims against the Investors. On September 7, 2023, the parties agreed to a schedule for briefing the motion to dismiss filed by the Directors and the Company (together, hereinafter, “Defendants”), with the understanding that the schedule would change if Plaintiff amended its Complaint rather than file a brief in opposition to Defendants’ motion to dismiss, and the parties also agreed to stay discovery pending resolution of the motion to dismiss. On September 19, 2023, the Company held its Annual Meeting at which, among other things, the Company’s two director nominees were re-elected and Plaintiff’s two director nominees were not elected. On September 21, 2023, Defendants filed their opening brief in support of their motion to dismiss. On October 20, 2023, Plaintiff filed an amended class action and derivative complaint (the “Amended Complaint”) against the Directors and naming the Company as a nominal defendant. The Amended Complaint makes many of the same allegations as the original Complaint. The Amended Complaint also purports to bring a claim on behalf of a class of holders of the Company’s common stock as of August 10, 2023, the record date for the Annual Meeting. The class claim alleges the Directors breached their fiduciary duties by causing the Company to enter into the Private Placement, setting the Annual Meeting record date for a date after the Private Placement closed, and holding the Annual Meeting more than thirteen months after the 2022 annual meeting. The Amended Complaint purports to bring a second claim for “wrongful dilution” derivatively on behalf of the Company. The derivative claim alleges the Directors “wrongfully diluted” Plaintiff and other stockholders by causing the Company to enter into the Private Placement in bad faith and for the purpose of entrenchment and not permitting Plaintiff and other stockholders to participate. The Amended Complaint seeks declarations that the Directors breached their fiduciary duties, that the votes cast at the Annual Meeting by the shares acquired in the Private Placement should be excluded from the final voting results, that Plaintiff’s two director nominees at the Annual Meeting were elected and that the Company’s nominees were not elected, as well as an order requiring the Company’s board of directors to recognize Plaintiff’s nominees as validly elected and remove the Company’s nominees from their positions on the board of directors. The Amended Complaint also seeks an order that the Company hold an annual meeting of stockholders in 2024 within thirteen months of the 2023 Annual Meeting, that the shares acquired in the Private Placement are enjoined from voting at the 2024 annual meeting, and awarding money damages in an unspecified amount. On November 3, 2023, Defendants filed a motion to dismiss the Amended Complaint. The Company believes the Plaintiff’s claims are baseless and intend to vigorously defend against them. On January 17, 2024, Plaintiff filed its brief in opposition to Defendants’ motion to dismiss. On February 8, 2024, Defendants filed their reply brief in further support of their motion to dismiss. On February 14, 2024, the Court held a hearing on the motion to dismiss, which is currently pending. Forte Biosciences, Inc. v. Camac Fund, LP, et al. , Case No. 3:23-cv-02399-N (N.D. Tex.) On October 28, 2023 , the Company filed a complaint (the “Complaint”), captioned Forte Biosciences , Inc. v. Camac Fund, LP, et al., Case No. 3:23-cv-02399-N, against Camac Fund, LP , Camac Partners, LLC, Camac Capital, LLC, and Eric Shahinian (collectively, “Camac”), as well as against Michael G. Hacke, Chris McIntyre, McIntyre Partnerships, LP, McIntyre Capital GP, LLC, McIntyre Capital Management, LP, McIntyre Capital Management GP, LLC, ATG Fund II LLC, ATG Capital Management, LLC, Gabriel Gliksberg, Funicular Funds, LP, The Funicular Fund, LP, Cable Car Capital LLC, Jacob Ma-Weaver, BML Investment Partners, L.P., BML Capital Management, LLC, and Braden M. Leonard (collectively with Camac, “Defendants”). The Complaint alleges that Defendants have been and are engaged in a campaign of deceit and misinformation in an attempt to force the Company to liquidate for Defendants’ benefit and to the detriment of the Company and other stockholders. The Company brings claims against Camac and certain other Defendants for issuing false and misleading proxy statements in connection with their attempts to elect two members of Forte’s board at the Company’s 2023 annual meeting in violation of Section 14(a) of the Securities Exchange Act of 1934 (the “Exchange Act”). The Company also brings claims against Defendants under Exchange Act Section 13(d) for failure to file and for filing misleading Schedule 13Ds, including because Defendants failed to disclose that they were coordinating as a group. The Company further alleges that Defendants tortiously interfered with Forte’s prospective business relationships, including by smearing the Company and manipulating the market for its stock to dissuade prospective investors from investing in the Company. The Complaint seeks declarations that Defendants violated Sections 14(a) and 13(d) of the Exchange Act, an order directing Defendants to file true and correct proxy statements and Schedule 13Ds, an injunction prohibiting Defendants from issuing future materially misleading and false public filings, and money damages to compensate the Company for Defendants’ violations of law. Defendants filed a Motion to Dismiss the Complaint on January 16, 2024. On February 6, 2024, the Company filed an Amended Complaint. The Amended Complaint makes many of the same allegations as the original Complaint and alleges two additional federal claims, one brought under Section 16(b) of the Exchange Act for recovery of short swing profits of the Defendants, and the other for declaratory relief under 28 U.S.C. § 2201. On February 15, 2024, the Company also filed a Motion for Relief from the PSLRA Discovery Stay and Speedy Hearing on Declaratory Judgment Act Claim, asking the Court to allow the Company to conduct limited, targeted discovery of documents and communications that demonstrate the full scope of the relationship between all Defendants and for an accounting of all short swing profits and trading records for all shares purchased or sold during the relevant time frame so the Company can fully account for short swing profits. Defendants filed a Motion to Dismiss the Amended Complaint on March 5, 2024, and on March 7, 2024, Defendants also filed a response in opposition to the Company’s Motion for Relief from the PSLRA Discovery Stay and Speedy Hearing on Declaratory Judgment Act. The Company believes its claims are meritorious and intends to pursue them vigorously to remedy Defendants’ violations of the law.

Equity

Equity	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Equity	7. Equity Preferred Stock The Company has 10 million authorized shares of Series A Preferred Stock, par value $ 0.001 , with no shares outstanding as of December 31, 2023 and 2022. Common Stock On July 31, 2023, the Company issued 15,166,957 shares of the Company’s common stock at a purchase price of $ 1.006 per Share and 9,689,293 pre-funded warrants to purchase shares of common stock at a purchase price of $ 1.005 per pre-funded warrant ("Private Placement") in connection with a Securities Purchase Agreement (the “Purchase Agreement”). The pre-funded warrants have an exercise price of $ 0.001 per share of common stock, are immediately exercisable and remain exercisable until exercised in full. The holders of pre-funded warrants may not exercise a pre-funded warrant if the holder, together with its affiliates, would beneficially own more than 9.99 % of the number of shares of common stock outstanding immediately after giving effect to such exercise. The holders of pre-funded warrants may increase or decrease such percentages not in excess of 19.99 % by providing at least 61 days’ prior notice to the Company. The warrants meet the criteria for equity classification and were therefore recorded at fair value as of the grant date as a component of stockholders’ equity within additional paid-in capital. The Purchase Agreement also provides certain investors a participation right in future offerings of the Company’s equity securities. In connection with the Private Placement, the Company filed a registration statement on Form S-3 that was declared effective on September 8, 2023. The gross proceeds of the Private Placement were approximately $ 25 million and the Company incurred $ 272 thousand in issuance costs. Certain executive officers, senior management, and board members of the Company participated in this Private Placement, purchasing approximately $ 1.16 million of shares of common stock at a purchase price of $ 1.01 per share. As of December 31, 2023, no pre-funded or common warrants were exercised, and there were pre-funded warrants to purchase an aggregate of 9,689,293 shares of common stock outstanding. The 9,689,293 shares of common stock issuable upon the exercise of the pre-funded warrants is not included in the number of issued and outstanding shares of common stock as of December 31, 2023. In June 2021, the Company filed a shelf registration statement on Form S-3 that went effective in June 2021 which will allow the Company to raise up to $ 300 million in additional capital. On March 31, 2022, the Company entered into an “at-the-market” equity offering program (“ATM Facility”) whereby the Company may from time to time offer and sell shares of its common stock up to an aggregate offering price of $ 25.0 million during the term of the ATM Facility. On April 1, 2022, the Company filed a prospectus supplement to the June 2021 Form S-3 relating to the offer and sale of the shares pursuant to the ATM Facility covering sales of up to $ 7.0 million of shares of common stock. On August 12, 2022, the Company filed an additional prospectus supplement relating to the offer and sale of shares pursuant to the ATM Facility covering sales of up to an additional $ 2.7 million of shares of common stock. The Company is not obligated to sell any shares under the ATM Facility. The ATM Facility may be terminated at any time upon ten days’ prior notice, or at any time in certain circumstances, including the occurrence of a material adverse effect on the Company. The Company has agreed to pay the sales agent a commission equal to 3.0 % of the gross proceeds from the sales of shares under the ATM Facility and has agreed to provide the sales agent with customary indemnification and contribution rights. The Company issued 6.1 million shares of common stock for gross proceeds of approximately $ 7.7 million under the ATM Facility from July 1, 2022 through December 31, 2022 and incurred $ 595 thousand in issuance costs related to the ATM Facility and shelf registration statement. While the ATM Facility remains in place, it remains restricted in its ability to access additional funding from the sale of securities under Form S-3. Warrants to purchase 4,434 shares of the Company’s common stock at an exercise price of $ 140.25 per share which were previously issued by Tocagen, survived the Merger and remained outstanding as of December 31, 2023 and 2022. These warrants have an expiration date of October 30, 2025 . These warrants meet the criteria for equity classification and were therefore recorded at fair value as of the grant date as a component of stockholders’ equity within additional paid-in capital. Shares of common stock reserved for future issuance were as follows: Shares Pre-funded warrants outstanding 9,689,293 Stock options outstanding 2,645,278 Reserved for issuance under equity incentive plans 2,570,194 RSUs outstanding 1,055,951 Reserved for issuance under employee stock purchase plan 511,022 Warrants outstanding 4,434 Total 16,476,172 Rights Plan On July 11, 2022, the Company authorized and declared a dividend distribution of one right (each, a “Right”) for each outstanding share of common stock of the Company to stockholders of record as of the close of business on July 21, 2022 . Each Right entitles the registered holder to purchase from the Company one one-thousandth of a share of Series A Participating Preferred Stock, par value $ 0.001 per share (the “Preferred Stock”), of the Company at an exercise price of $ 16.00 per one one-thousandth of a share of Preferred Stock, subject to adjustment. The Rights are not exercisable until the Distribution Date. The Distribution Date is the 10th business day after the public announcement that a person or group of affiliated or associated persons has acquired beneficial ownership of 10 percent or more of our common stock or the 10th business day after a person or group announces a tender or exchange offer that would result in ownership by a person or group of 10 percent or more of our common stock. The Rights will be redeemable at the Company’s option for $ 0.001 per Right at any time on or prior to the 10th business day after the public announcement that an Acquiring Person has acquired beneficial ownership of 10 percent or more of the Common Stock. On June 26, 2023, the Company entered into Amendment No. 1 to the Rights Agreement which extends the expiration of the Rights to July 12, 2024 , unless the Rights are earlier redeemed or exchanged in accordance with the terms of the Rights Agreement. There were no other changes to the terms and conditions of the Rights Agreement in connection with such amendment. On July 28, 2023, the Company entered into Amendment No. 2 to the Rights Agreement, which prevents the approval, execution, delivery or performance of the Purchase Agreement or the pre-funded warrants, or the consummation of any of the transactions contemplated by the Purchase Agreement or the pre-funded warrants, including any issuance of the Company's common stock pursuant to the terms of the Purchase Agreement or the pre-funded warrants, from, among other things, (i) causing or permitting the Rights to be exercised or exchanged, or (ii) causing any Purchaser or any of their respective affiliates to be deemed an Acquiring Person (as defined in the Rights Agreement) for any purpose under the Rights Agreement. The Rights were determined to have no value upon issuance and no rights were exercisable as of December 31, 2023.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	8. Stock-Based Compensation Equity Plans The Company inherited the 2017 Equity Incentive Plan (the "2017 Plan") as part of its merger with Tocagen, Inc. in June 2020. The 2017 Plan was terminated in May 2021 and replaced by the 2021 Equity Incentive Plan (the “2021 Plan”). The 2017 Plan will continue to govern outstanding awards issued under the 2017 Plan. The 2021 Plan had an initial reserve of 1,000,000 shares available for grant. The 2021 Plan was amended in June 2022 to increase the shares available for grant by an additional 1,500,000 shares. The 2021 Plan was amended and restated in September 2023 to increase the shares available for grant by an additional 2,500,000 shares. The 2021 Plan provides for the grant of incentive stock options (“ISOs”), non-statutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance-based stock awards, other forms of equity compensation and performance cash awards. ISOs may be granted only to employees. All other awards may be granted to employees, including officers, and to non-employee directors and consultants of the Company and its affiliates. Service-based awards generally vest over a four-year period, with the first 25 % of such awards vesting following twelve months of continued employment or service with the remaining awards vesting monthly in equal installments over the following thirty-six months . For certain service-based awards to the board of directors, vesting occurs in thirty-six equal monthly installments over a three-year period for initial grants and in twelve equal monthly installments over a twelve-month period for subsequent grants . As of December 31, 2023 , there were 2,495,194 shares available for issuance under the 2021 Plan. On July 26, 2020, the Company adopted the 2020 Inducement Equity Incentive Plan (the “2020 Inducement Plan”) and reserved 500,000 shares for future grant under the 2020 Inducement Plan. As of December 31, 2023 , there were 75,000 shares available for issuance under the 2020 Inducement Plan. Stock Options The risk-free interest rate assumption for stock options is based on the U.S. Treasury yield curve rate at the date of grant with a maturity approximating the expected term of the option. All option awards generally expire ten years from the date of grant. The expected term assumption for options granted to employees is determined using the simplified method that represents the average of the contractual term of the option and the weighted average vesting period of the option. The Company uses the simplified method because it does not have sufficient historical option exercise data to provide a reasonable basis upon which to estimate expected term. Due to the Company’s limited trading of its common stock and lack of company-specific historical or implied volatility data, the Company has based its estimate of expected volatility on the historical volatility of a group of similar companies in the life sciences industry whose shares are publicly traded. The Company selects the peer group based on comparable characteristics, including development stage, product pipeline, and market capitalization. The Company computes historical volatility data using the daily closing prices for the selected companies’ shares during the equivalent period of the calculated expected term of the stock-based awards. The Company will continue to apply this process until sufficient amount of historical information regarding the volatility of its own stock price become available. The assumed dividend yield is based upon the Company’s expectation of not paying dividends in the foreseeable future. The fair value per share of common stock is the closing stock price on the option grant date. The weighted average grant-date fair value of stock options granted in the years ended December 31, 2023 and 2022 was $ 0.66 and $ 0.91 , respectively. The weighted-average assumptions used to value these stock options using the Black-Scholes option-pricing model were as follows. Year ended Year Ended December 31, 2022 Fair value of common stock $ 0.78 $ 1.47 Risk-free interest rate 4.30 % 2.31 % Dividend yield 0.00 % 0.00 % Expected term of options (years) 5.62 5.88 Volatility 114.50 % 68.75 % The table below summarizes the stock option activity during the year ended December 31, 2023: Number of Weighted- Weighted- Aggregate Balances at December 31, 2022 2,363,195 $ 9.29 8.22 $ 65 Granted 345,000 $ 0.78 — — Exercised — — — — Cancelled/Forfeited ( 62,917 ) $ 5.85 — — Balances at December 31, 2023 2,645,278 $ 8.26 7.17 $ 30 Vested and expected to vest at December 31, 2023 2,645,278 $ 8.26 7.17 $ 30 Exercisable at December 31, 2023 1,332,746 $ 12.02 7.00 $ 5 The aggregate intrinsic value of stock options as of December 31, 2023 is based on the Company’s closing stock price of $ 0.82 per share. Restricted Stock Unit Awards There were 1,100,000 restricted stock units granted during year ended December 31, 2023 with one sixteenth of the restricted stock units vesting every quarter. The Company made a change in accounting estimate in the year ended December 31, 2022 related to the vesting of performance-based restricted stock units. As a result of this change in accounting estimate, $ 158 thousand of expense that had been previously recognized in 2021 was reversed in the year ended December 31, 2022. Restricted stock unit award transactions during the year ended December 31, 2023 were as follows: Weighted Avg Grant Date Shares Fair Value Outstanding at December 31, 2022 162,201 $ 3.36 Granted 1,100,000 1.01 Forfeited/Cancelled — — Issued as Common Stock ( 206,250 ) 0.90 Outstanding at December 31, 2023 1,055,951 $ 1.37 The aggregate fair value of RSUs vested during the year ended December 31, 2023 was $ 186 thousand. 2017 Employee Stock Purchase Plan In May 2021, the Company’s board of directors reactivated the Company’s 2017 Employee Stock Purchase Plan (“ESPP”) which had previously been suspended. The ESPP allows eligible employees to withhold up to 15 % of their earnings to purchase shares of the Company’s common stock at a price per share equal to the lower of (i) 85 % of the fair market value of a share of the Company’s common stock on the first date of an offering or (ii) 85 % of the fair market value of a share of the Company’s common stock on the date of purchase. The Company had 511,022 shares available for future issuance under the ESPP as of December 31, 2023 . The number of shares of common stock reserved for issuance will automatically increase on January 1 of each calendar year through January 1, 2027, by the lesser of (a) 1 % of the total number of shares of the Company’s common stock outstanding on December 31 of the preceding calendar year, (b) 300,000 shares, or (c) a number determined by the Company’s board of directors that is less than (a) and (b). The Company issued 17,500 and 5,716 shares under the ESPP during the year ended December 31, 2023 and 2022, respectively. The ESPP is considered a compensatory plan. The Company recorded stock-based compensation expense related to its ESPP of $ 12 thousand and $ 3 thousand for the years ended December 31, 2023 and 2022, respectively. The fair value of the rights granted to employees under the ESPP was estimated using a Black-Scholes option-pricing model with the following weighted-average valuation assumptions: Year ended Year Ended December 31, 2022 Fair value of common stock $ 1.05 $ 1.32 Risk-free interest rate 5.20 % 2.52 % Dividend yield 0.00 % 0.00 % Expected term of options (years) 0.50 0.51 Volatility 119.32 % 76.71 % Stock-Based Compensation Expense Stock-based compensation expenses included in the Company’s consolidated statements of operations and comprehensive loss for the years ended December 31, 2023 and 2022 are as follows (in thousands): Year Ended December 31, 2023 2022 Research and development $ 1,201 $ 1,270 General and administrative 2,083 2,745 Total $ 3,284 $ 4,015 As of December 31, 2023 , there was unrecognized stock-based compensation expense of $ 4.1 million related to stock options and restricted stock units with service conditions, which is expected to be recognized over a weighted-average period of 1.68 years. Total unrecognized stock-based compensation as of December 31, 2023 was approximately $ 0.5 million related to restricted stock units with performance based vesting. The performance based conditions are tied to development milestones which have not been met.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	9. Income Taxes For the years ended December 31, 2023 and 2022 , the Company did no t record a current or deferred income tax expense or benefit due to a valuation allowance position. The benefit for income taxes differs from the amount of income tax determined by applying the applicable U.S. statutory federal income tax rate to pretax income as a result of the following differences (in thousands): Year Ended December 31, 2023 2022 Income tax expense (benefit) at federal statutory rate $ ( 6,610 ) 21.0 % $ ( 2,915 ) 21.0 % Increase/(decrease) in tax resulting from: State income taxes — 0.0 % ( 79 ) 0.6 % Change in valuation allowance 6,541 - 20.8 % 2,628 - 18.9 % Stock-based compensation expense 60 - 0.2 % 370 - 2.7 % Other 9 0.0 % ( 4 ) 0.0 % Total $ — 0.0 % $ — 0.0 % The primary components of temporary differences which give rise to the Company’s net deferred tax assets and liabilities as of December 31, 2023 and 2022 are as follows (in thousands): Year Ended December 31, 2023 2022 Deferred tax assets: Accrual to cash adjustment $ 433 $ 480 Start-up costs 4,508 2,949 Patent costs 40 40 Stock-based compensation expense 1,627 1,391 Net operating loss 6,515 6,039 Capitalized R&D 4,940 978 Other deferred taxes 11 10 R&D credits 528 328 Total noncurrent deferred tax assets 18,602 12,215 Valuation Allowance ( 18,602 ) ( 12,215 ) Net deferred tax assets after valuation allowance $ — $ — Beginning January 1, 2022, the Tax Cuts and Jobs Act (the "Tax Act”) eliminated the option to deduct research and development expenditures in the current year and requires taxpayers to capitalize such expenses pursuant to Internal Revenue Code (“IRC”) Section 174. The capitalized expenses are amortized over a 5-year period for domestic expenses and a 15-year period for foreign expenses. As a result of this provision of the Tax Act, deferred tax assets related to capitalized research expenses increased by $ 4.0 million during the year ended December 31, 2023. The Company has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets. Based upon the Company’s history of operating losses, the Company has concluded that it is more likely than not that the benefit of its deferred tax assets will not be realized. Accordingly, the Company has provided a full valuation allowance for deferred tax assets as of December 31, 2023 and 2022. During 2023 and 2022 , the valuation allowance increased by $ 6.4 million and $ 2.6 million, respectively. As of December 31, 2023 , the Company has federal and California research and development tax credit carryforwards of approximately $ 447 thousand and $ 389 thousand, respectively. The federal research and development tax credits begin to expire in 2041 unless previously utilized. The California credits do not expire. Net operating losses and tax credit carryforwards as of December 31, 2023are as follows (in thousands): Amount Expiration Years Net operating losses, federal (Post December 31, 2017) $ 27,153 Do Not Expire Net operating losses, federal (Pre January 1, 2018) $ 11 2037 Net operating losses, state $ 11,602 2037 Tax credits, federal $ 447 2041 Tax credits, state $ 389 Indefinite The Company is subject to taxation in the U.S. and California. As of December 31, 2023, Tocagen’s tax years beginning 2007 to date are subject to examination by federal and California taxing authorities due to the carry forward of unutilized net operating losses and research and development tax credits. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the Internal Revenue Service or state tax authorities to the extent utilized in a future period. Pursuant to Internal Revenue Code (IRC) Sections 382 and 383, annual use of a company’s net operating loss and tax credit carryforwards may be limited if there is a cumulative change in ownership of greater than 50 % (by value) within a three-year period. The amount of the annual limitation is determined based on the value of the Company immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has completed several equity offerings since its inception which may have resulted in a change in control as defined by Sections 382 and 383 of the IRC, or could result in a change in control in the future. The Company has not completed an IRC Section 382 and 383 analysis regarding the limitation of net operating loss and research and development credit carryforwards. Upon completion of such an analysis, there may be either increases or decreases to the reported amount of the deferred tax assets for net operating losses and federal and California research and development credits. Any change in the amount of the deferred tax assets would have a corresponding change in the valuation allowance, and therefore is not expected to impact the Company’s effective tax rate. The Company’s policy is to record interest and penalties relating to uncertain tax positions as a component of income tax expense should the Company believe there is an uncertain tax position liability. As of December 31, 2023, and 2022 , there was no accrued interest or penalties for uncertain positions. The Company does not expect that the unrecognized tax benefits will change within 12 months of this reporting date. Due to the existence of the valuation allowance, future changes in the Company’s unrecognized tax benefits will not impact the Company’s effective tax rate.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2023
Related Party Transactions [Abstract]
Related Party Transactions	10. Related Party Transactions Two members of the Company’s board of directors received cash payments of $ 9 thousand and $ 7 thousand for scientific consulting services during the year ended December 31, 2022. The Company had no outstanding accounts payable to either of these directors as of December 31, 2022. There were no related party transactions during the year ended December 31, 2023 other than certain executive officers, senior management, and board members of the Company participating in the Private Placement as described in Note 7 above.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The Company prepares its consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“GAAP”), as found in the Accounting Standards Codification (“ASC”), the Accounting Standards Update (“ASU”), of the Financial Accounting Standards Board (“FASB”), and the rules and regulations of the US Securities and Exchange Commission (“SEC”).
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries, Forte Subsidiary, Inc. Forte Biosciences Emerald Limited and Forte Biosciences Australia Proprietary Limited. All intercompany accounts and transactions have been eliminated in the preparation of the consolidated financial statements.
Use of Estimates	Use of Estimates The preparation of the Company’s consolidated financial statements requires management to make estimates and assumptions that impact the reported amounts of assets, liabilities, expenses and the disclosure of contingent assets and liabilities in the Company’s consolidated financial statements and accompanying notes. Significant management estimates that affect the reported amounts of assets, liabilities and expenses include stock-based compensation expense and accruals for clinical trials and drug manufacturing. 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.
Segment Information	Segment Information The Company operates as a single operating segment. The Company’s chief operating decision maker, its Chief Executive Officer, manages the Company’s operations on a consolidated basis for the purposes of allocating resources, making operating decisions and evaluating financial performance.
Cash and Cash Equivalents	Cash and cash equivalents Cash and cash equivalents include U.S. Treasury bills, money market funds and deposits with commercial banks. Cash equivalents are defined as short-term, highly liquid investments with original maturities of 90 days or less at the date of purchase.
Available-for-Sale Securities	Available-for-Sale Securities The Company’s available-for-sale securities primarily consist of U.S. government and agency securities. Securities with maturities from the date of purchase of less than three months are included in cash equivalents. The Company classifies its marketable securities as available-for-sale and records such assets at estimated fair value in the consolidated balance sheets, with unrealized gains and losses, if any, reported as a component of other comprehensive income (loss) within the consolidated statements of operations and comprehensive loss and as a separate component of stockholders’ equity. Realized gains and losses are calculated on the specific identification method and recorded as interest income (loss). Any premium arising at purchase is amortized to the earliest call date and any discount arising at purchase is accreted to maturity. Accretion of discounts are recorded in interest income in the consolidated statements of operations and comprehensive loss.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There is a three-level hierarchy that prioritizes the inputs used in determining fair value by their reliability and preferred use as follows: • Level 1 - Valuations based on quoted prices in active markets for identical assets or liabilities. • Level 2 – Valuations based on quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data. • Level 3 – Valuations based on inputs that are both significant to the fair value measurements and are unobservable. To the extent that a valuation is based on models or inputs that are less observable, or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized within Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. There have been no significant changes to the valuation methods utilized by the Company during the periods presented. There have been no transfers between Level 1, Level 2, and Level 3 in any periods presented. The carrying amounts of financial instruments consisting of cash and cash equivalents, accounts payable, accrued liabilities included in the Company’s financial statements are reasonable estimates of fair value, primarily due to their short maturities.
Property and Equipment	Property and Equipment, Net Property and equipment are stated at cost less accumulated depreciation, subject to review for impairment. Property and equipment, net are depreciated over the estimated useful lives of the assets, generally three to five years , using the straight-line method.
Impairment of Property and Equipment	Impairment of Property and Equipment The Company reviews its property and equipment for impairment when events or changes in circumstances indicate the carrying value of the assets may not be recoverable. Recoverability is measured by comparing the book values of the assets to future net undiscounted cash flows that the assets or the asset groups are expected to generate. If such assets are considered impaired, the impairment to be recognized is measured by the amount the book value of the assets exceed their fair value, which is measured based on the estimated discounted future net cash flows arising from the assets or asset groups. No impairment losses on property and equipment have been recorded for the year ended December 31, 2023 or 2022.
Pre-Funded Warrants	Pre-Funded Warrants Pre-funded warrants are accounted for as either derivative liabilities or as equity instruments depending on the specific terms of the agreement. The pre-funded warrants are equity-classified instruments that were recorded in additional paid-in capital at issuance and are not subject to remeasurement. The Company periodically evaluates changes in facts and circumstances that could impact the classification of warrants.
Research and Development Costs	Research and Development Costs Research and development costs are expensed as incurred. Research and development costs consist primarily of salaries and benefits of research and development personnel, costs related to research activities, preclinical studies, clinical trials and drug manufacturing. Non-refundable advance payments for goods or services that will be used in future research and development activities are deferred and capitalized and are only expensed when the goods have been received or when the service has been performed rather than when the payment is made. Drug manufacturing and clinical trial costs are a component of research and development expenses. The Company expenses costs for its drug manufacturing activities performed by Contract Manufacturing Organizations (“CMOs”), preclinical and clinical trial costs performed by Contract Research Organizations (“CROs”) and other service providers, as they are incurred, based upon estimates of the work completed over the life of the individual study in accordance with associated agreements. The Company uses information it receives from internal personnel and outside service providers to estimate the percentage of completion and therefore the expense to be incurred.
Patent Costs	Patent Costs Costs related to filing and pursuing patent applications, including direct application fees and the legal and consulting expenses related to making such applications, are expensed as incurred, as recoverability of such expenditures is uncertain. These costs are included in general and administrative expenses within the consolidated statements of operations and comprehensive loss.
Comprehensive Loss	Comprehensive Los s Comprehensive loss is defined as the change in equity during a period from transactions from non-owner sources. Other comprehensive loss includes unrealized gains on available-for-sale securities, which was the only difference between net loss and comprehensive loss for the applicable periods.
Net Loss Per Share	Net Loss Per Share The Company’s net loss is equivalent to net loss attributable to common stockholders for all periods presented. Basic net loss per share is computed by dividing net loss applicable to common stockholders by the weighted average number of common shares, without consideration for common stock equivalents. The weighted average number of shares of common stock used in the basic and diluted net loss per share calculation include the pre-funded warrants outstanding during the period as they are exercisable at any time and their exercise requires only nominal consideration for the delivery of shares. As of December 31, 2023, no pre-funded warrants have been exercised and there were pre-funded warrants to purchase an aggregate of 9,689,293 shares of common stock outstanding. Diluted net loss per share is computed by dividing net loss by the weighted-average number of shares of common stock and common stock equivalents outstanding during the period in accordance with the treasury stock method. The following number of unexercised stock options, restricted stock units, warrants, and shares expected to be purchased under the ESPP, which are common stock equivalents, have been excluded from the diluted net loss calculation as their effect would have been anti-dilutive for the periods presented: Year Ended December 31, 2023 2022 Options 2,645,278 2,363,195 Restricted stock units 1,055,951 162,201 Warrants 4,434 4,434 ESPP 1,847 — Total 3,707,510 2,529,830
Stock-Based Compensation	Stock-Based Compensation The Company issues stock-based awards to employees, directors and non-employees, generally in the form of stock options, restricted stock units or rights granted to employees under the Employee Stock Purchase Plan (“ESPP”). The Company accounts for stock-based compensation awards in accordance with ASC Topic 718, Compensation—Stock Compensation . The Company measures compensation cost for all equity awards for employees, directors and non-employees at their grant-date fair value and recognizes compensation expense for service-based awards on a straight-line basis over the requisite service period, which is generally the vesting period. The grant-date fair value of stock options is estimated using the Black-Scholes option pricing model. The grant-date fair value of restricted stock units is determined using the Company’s closing stock price on the date of grant. Forfeitures are recognized as they occur. Stock-based compensation expense for an award with a performance condition is recognized when the achievement of the performance condition has been determined to be probable. If the outcome of such performance condition has not been determined to be probable, or has not been met, no compensation expense is recognized and any previously recognized compensation expense is reversed. For rights granted under the ESPP, the fair value of each purchase is estimated at the beginning of the offering period using the Black-Scholes option pricing model. The Company classifies stock-based compensation expense in its statement of operations in the same manner in which the award recipient’s salary and related costs are classified in the case of employees, or in which the award recipient’s service payments are classified in the case of directors and non-employees.
Foreign Currency Transactions	Foreign Currency Transactions Transaction gains and losses that arise from exchange rate fluctuations on transactions denominated in currencies other than the US dollar are recorded to other expenses, net in the consolidated statements of operations and comprehensive loss and were not material for the periods presented. The Company's subsidiaries use the U.S. dollar as their functional currency.
Income Taxes	Income Taxes The Company uses an asset and liability approach to account for income taxes. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax bases of assets and liabilities. These differences are measured using the enacted statutory tax rates that are expected to be in effect for the years in which differences are expected to reverse. Valuation allowances are provided when the expected realization of deferred tax assets does not meet a “more likely than not” criterion. The Company makes estimates and judgments about its future taxable income that are based on assumptions that are consistent with its plans and estimates. Should the actual amounts differ from those estimates, the amount of the valuation allowance could be materially impacted. Changes in these estimates may result in significant increases or decreases to the Company’s tax provision in a period in which such estimates are changed, which in turn would affect net income or loss. The Company recognizes tax benefits from uncertain tax positions if it believes the position is more likely than not to be sustained on examination by the taxing authorities based on the technical merits of the position. The Company makes adjustments to these reserves when facts and circumstances change, such as the closing of a tax audit or the refinement of an estimate. The provision for income taxes includes the effects of any reserves for tax positions that are not more likely than not to be sustained, as well as the related net interest and penalties.
Recently Issued Accounting Standards Not Yet Adopted	Recently Issued Accounting Standards Not Yet Adopted From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and are adopted by the Company as of a specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on the Company’s financial position or results of operations. In August 2020, the FASB issued ​ASU 2020-06​, ​Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in an Entity’s Own Equity (Subtopic 815-40)​ (“ASU 2020-06”). ​ASU 2020-06 eliminates the beneficial conversion and cash conversion accounting models for convertible instruments. It also amends the accounting for certain contracts in an entity’s own equity that are currently accounted for as derivatives because of specific settlement provisions. In addition, ASU 2020-06 modifies how particular convertible instruments and certain contracts that may be settled in cash or shares impact the diluted earnings per share computation. The amendments in ASU 2020-06 are effective for smaller reporting companies as defined by the SEC for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early adoption is permitted, but not earlier than fiscal years beginning after December 15, 2020. The Company is currently evaluating the impact of ASU 2020-06 on its consolidated financial statements and does not expect the adoption of this amended guidance to have a material impact on the Company’s consolidated financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Schedule of Common Stock Equivalents Excluded from Diluted Net Loss Calculation	The following number of unexercised stock options, restricted stock units, warrants, and shares expected to be purchased under the ESPP, which are common stock equivalents, have been excluded from the diluted net loss calculation as their effect would have been anti-dilutive for the periods presented: Year Ended December 31, 2023 2022 Options 2,645,278 2,363,195 Restricted stock units 1,055,951 162,201 Warrants 4,434 4,434 ESPP 1,847 — Total 3,707,510 2,529,830

Balance Sheet Components (Table

Balance Sheet Components (Tables)	12 Months Ended
	Dec. 31, 2023
Balance Sheet Related Disclosures [Abstract]
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets as of December 31, 2023 and 2022 consist of the following (in thousands): December 31, 2023 December 31, 2022 Prepaid professional fees $ 413 $ — Prepaid insurance 318 341 Prepaid manufacturing & research expense 306 — Other 165 70 Total Prepaid Expenses and Other Current Assets $ 1,202 $ 411
Schedule of Property and Equipment	Property and equipment, net as of December 31, 2023 and 2022 consist of the following (in thousands): December 31, 2023 December 31, 2022 Equipment $ 100 $ — Furniture and Fixtures 18 — Property and equipment, at cost 118 — Less accumulated depreciation ( 9 ) — Total property and equipment, net $ 109 $ —
Schedule of Other Assets	Other assets as of December 31, 2023 and 2022 consist of the following (in thousands): December 31, 2023 December 31, 2022 Prepaid insurance $ 280 $ 473 Prepaid professional fees 211 - Other 53 13 Total Other Assets $ 544 $ 486
Components of Accrued Liabilities	Accrued liabilities as of December 31, 2023 and 2022 consist of the following (in thousands): December 31, 2023 December 31, 2022 Accrued manufacturing and clinical expenses $ 1,016 $ 485 Accrued compensation 947 890 Accrued legal and professional fees 276 643 Accrued other expenses 3 8 Total Accrued Liabilities $ 2,242 $ 2,026

Fair Value (Tables)

Fair Value (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Schedule of Financial Assets Measured at Fair Value on a Recurring Basis	The following tables provides a summary of the assets that are measured at fair value on a recurring basis as of December 31, 2023 and December 31, 2022 (in thousands): Fair Value Measurements as of Level 1 Level 2 Level 3 Total Cash equivalents: Money Market Funds $ 5,686 $ — $ — $ 5,686 U.S. Treasury Bills $ — $ 25,164 $ — $ 25,164 Total $ 5,686 $ 25,164 $ — $ 30,850 Fair Value Measurements as of Level 1 Level 2 Level 3 Total Cash equivalents: Money Market Funds $ 5,061 $ — $ — $ 5,061 Total $ 5,061 $ — $ — $ 5,061

Available-for-sale Securities (

Available-for-sale Securities (Tables)	12 Months Ended
	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Summary of Available-for-sale Securities	The following table summarizes the Company's available-for-sale securities as of December 31, 2023 (in thousands). There were no available-for-sale securities with an unrealized loss as of December 31, 2023. The Company did no t have available-for-sale securities as of December 31, 2022. December 31, 2023 Unrealized Amortized Cost Gains Losses Estimated Fair Value Cash equivalents U.S. Treasury Bills $ 25,160 $ 4 $ — $ 25,164 Total available-for-sale securities $ 25,160 $ 4 $ — $ 25,164
Schedule of Available-for-sale Securities by Maturity	As of December 31, 2023, the Company classified available-for-sales as cash equivalents in the consolidated balance sheet because the maturity dates were less than three months from the date of the purchase. The following table summarizes available-for-sale securities by maturity as of December 31, 2023 (in thousands): Amortized Cost Estimated Fair Value Due in one year or less $ 25,160 $ 25,164 Due after one year — — Total available-for-sale securities $ 25,160 $ 25,164

Equity (Tables)

Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Schedule of Common Stock Reserved for Future Issuance	Shares of common stock reserved for future issuance were as follows: Shares Pre-funded warrants outstanding 9,689,293 Stock options outstanding 2,645,278 Reserved for issuance under equity incentive plans 2,570,194 RSUs outstanding 1,055,951 Reserved for issuance under employee stock purchase plan 511,022 Warrants outstanding 4,434 Total 16,476,172

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Summary of Weighted-Average Assumptions Used to Value Stock Options	The weighted-average assumptions used to value these stock options using the Black-Scholes option-pricing model were as follows. Year ended Year Ended December 31, 2022 Fair value of common stock $ 0.78 $ 1.47 Risk-free interest rate 4.30 % 2.31 % Dividend yield 0.00 % 0.00 % Expected term of options (years) 5.62 5.88 Volatility 114.50 % 68.75 %
Summary of Stock Option Activity	The table below summarizes the stock option activity during the year ended December 31, 2023: Number of Weighted- Weighted- Aggregate Balances at December 31, 2022 2,363,195 $ 9.29 8.22 $ 65 Granted 345,000 $ 0.78 — — Exercised — — — — Cancelled/Forfeited ( 62,917 ) $ 5.85 — — Balances at December 31, 2023 2,645,278 $ 8.26 7.17 $ 30 Vested and expected to vest at December 31, 2023 2,645,278 $ 8.26 7.17 $ 30 Exercisable at December 31, 2023 1,332,746 $ 12.02 7.00 $ 5
Summary of Restricted Stock Unit Award Transactions	Restricted stock unit award transactions during the year ended December 31, 2023 were as follows: Weighted Avg Grant Date Shares Fair Value Outstanding at December 31, 2022 162,201 $ 3.36 Granted 1,100,000 1.01 Forfeited/Cancelled — — Issued as Common Stock ( 206,250 ) 0.90 Outstanding at December 31, 2023 1,055,951 $ 1.37
Summary of Stock-Based Compensation Expenses	Stock-based compensation expenses included in the Company’s consolidated statements of operations and comprehensive loss for the years ended December 31, 2023 and 2022 are as follows (in thousands): Year Ended December 31, 2023 2022 Research and development $ 1,201 $ 1,270 General and administrative 2,083 2,745 Total $ 3,284 $ 4,015
ESPP
Summary of Weighted-Average Assumptions Used to Value Stock Options	The fair value of the rights granted to employees under the ESPP was estimated using a Black-Scholes option-pricing model with the following weighted-average valuation assumptions: Year ended Year Ended December 31, 2022 Fair value of common stock $ 1.05 $ 1.32 Risk-free interest rate 5.20 % 2.52 % Dividend yield 0.00 % 0.00 % Expected term of options (years) 0.50 0.51 Volatility 119.32 % 76.71 %

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Summary of Reconciliations of Income Tax	The benefit for income taxes differs from the amount of income tax determined by applying the applicable U.S. statutory federal income tax rate to pretax income as a result of the following differences (in thousands): Year Ended December 31, 2023 2022 Income tax expense (benefit) at federal statutory rate $ ( 6,610 ) 21.0 % $ ( 2,915 ) 21.0 % Increase/(decrease) in tax resulting from: State income taxes — 0.0 % ( 79 ) 0.6 % Change in valuation allowance 6,541 - 20.8 % 2,628 - 18.9 % Stock-based compensation expense 60 - 0.2 % 370 - 2.7 % Other 9 0.0 % ( 4 ) 0.0 % Total $ — 0.0 % $ — 0.0 %
Components of Net Deferred Tax Assets and Liabilities	The primary components of temporary differences which give rise to the Company’s net deferred tax assets and liabilities as of December 31, 2023 and 2022 are as follows (in thousands): Year Ended December 31, 2023 2022 Deferred tax assets: Accrual to cash adjustment $ 433 $ 480 Start-up costs 4,508 2,949 Patent costs 40 40 Stock-based compensation expense 1,627 1,391 Net operating loss 6,515 6,039 Capitalized R&D 4,940 978 Other deferred taxes 11 10 R&D credits 528 328 Total noncurrent deferred tax assets 18,602 12,215 Valuation Allowance ( 18,602 ) ( 12,215 ) Net deferred tax assets after valuation allowance $ — $ —
Summary of Net Operating Losses and Tax Credit Carryforwards	Net operating losses and tax credit carryforwards as of December 31, 2023are as follows (in thousands): Amount Expiration Years Net operating losses, federal (Post December 31, 2017) $ 27,153 Do Not Expire Net operating losses, federal (Pre January 1, 2018) $ 11 2037 Net operating losses, state $ 11,602 2037 Tax credits, federal $ 447 2041 Tax credits, state $ 389 Indefinite

Organization and Description _2

Organization and Description of Business - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ 118,520	$ 87,044
Cash used in operating activities	(28,706)	(8,185)
Cash and cash equivalents	$ 37,125	$ 41,100

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Schedule Of Significant Accounting Policies [Line Items]
Transfers between fair value hierarchy levels	$ 0
Impairment losses on property and equipment	$ 0	$ 0
Number of prefunded or common stock warrants exercised	0
Common Stock
Schedule Of Significant Accounting Policies [Line Items]
Warrants outstanding	9,689,293
Minimum
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful life of assets	3 years
Maximum
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful life of assets	5 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Common Stock Equivalents Excluded from Diluted Net Loss Calculation (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted net loss calculation	3,707,510	2,529,830
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted net loss calculation	2,645,278	2,363,195
Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted net loss calculation	1,055,951	162,201
Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted net loss calculation	4,434	4,434
ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted net loss calculation	1,847

Balance Sheet Components - Sche

Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Prepaid professional fees	$ 413
Prepaid insurance	318	$ 341
Prepaid manufacturing & research expense	306
Other	165	70
Total Prepaid Expenses and Other Current Assets	$ 1,202	$ 411

Balance Sheet Components - Sc_2

Balance Sheet Components - Schedule of Property and Equipment (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 118
Less accumulated depreciation	(9)
Total property and equipment, net	109
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	100
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 18

Balance Sheet Components - Sc_3

Balance Sheet Components - Schedule of Other Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Prepaid insurance	$ 280	$ 473
Prepaid professional fees	211
Other	53	13
Total Other Assets	$ 544	$ 486

Balance Sheet Components - Comp

Balance Sheet Components - Components of Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Accrued manufacturing and clinical expenses	$ 1,016	$ 485
Accrued compensation	947	890
Accrued legal and professional fees	276	643
Accrued other expenses	3	8
Total Accrued Liabilities	$ 2,242	$ 2,026

Fair Value - Schedule of Financ

Fair Value - Schedule of Financial Assets Measured at Fair Value on a Recurring Basis (Details) - Recurring - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 30,850	$ 5,061
U.S. Treasury Bills
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	25,164
Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	5,686	5,061
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	5,686	5,061
Level 1 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	5,686	$ 5,061
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	25,164
Level 2 | U.S. Treasury Bills
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 25,164

Available-for-sale Securities -

Available-for-sale Securities - Additional Information (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Available-for-sale securities	$ 25,164,000	$ 0
Available-for-sale securities with an unrealized loss	$ 0

Available-for-sale Securities_2

Available-for-sale Securities - Schedule of Available-for-sale Securities (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Available-for-sale securities, Amortized Cost	$ 25,160,000
Available-for-sale securities, Unrealized Gains	4,000
Available-for-sale securities, Estimated Fair Value	25,164,000	$ 0
U.S. Treasury Bills
Debt Securities, Available-for-Sale [Line Items]
Available-for-sale securities, Amortized Cost	25,160,000
Available-for-sale securities, Unrealized Gains	4,000
Available-for-sale securities, Estimated Fair Value	$ 25,164,000

Available-for-sale Securities_3

Available-for-sale Securities - Schedule of Available-for-sale Securities by Maturity (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Due in one year or less, Amortized Cost	$ 25,160,000
Available-for-sale securities, Amortized Cost	25,160,000
Due in one year or less, Estimated Fair Value	25,164,000
Available-for-sale securities, Estimated Fair Value	$ 25,164,000	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands				12 Months Ended
	Oct. 28, 2023	Aug. 10, 2023	Jul. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Commitments And Contingencies [Line Items]
FDIC insured amount				$ 250
Rent expenses				129	$ 19
Contractual obligation				$ 451
Complaint filed, date	October 28, 2023	August 10, 2023
Name of plaintiff	Forte Biosciences	Camac Fund LP
Name of defendant	Camac Fund, LP	members of the Company’s Board of Directors (the “Directors”) and entities affiliated with certain of the Company’s investors (the “Investors”) and naming the Company as nominal defendant.
Gross proceeds of private placement			$ 25,000

Equity - Additional Information

Equity - Additional Information (Details) $ / shares in Units, $ in Thousands						6 Months Ended	12 Months Ended
	Jul. 31, 2023 USD ($) $ / shares shares	Aug. 12, 2022 USD ($)	Jul. 11, 2022 Right $ / shares shares	Apr. 01, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Jun. 16, 2020 $ / shares shares
Class Of Stock [Line Items]
New issuance of common stock								$ 7,122
Number of prefunded or common stock warrants exercised | shares							0
Gross proceeds of private placement	$ 25,000
Warrants expiration date							Jul. 12, 2024
Dividend payable, date of record			Jul. 21, 2022
At The Market Equity Offering Program
Class Of Stock [Line Items]
Gross proceeds from issuance of common stock					$ 25,000
Percentage of sales commission					3%
Rights Agreement
Class Of Stock [Line Items]
Percentage of beneficial ownership acquired by a person or group of affiliated or associated persons			10%
Percentage of ownership by a person or group upon announcement of tender or exchange offer			10%
Percentage of beneficial ownership acquired by an acquiring person after public announcement			10%
Maximum | At The Market Equity Offering Program
Class Of Stock [Line Items]
Gross proceeds from issuance of common stock				$ 7,000
New issuance of common stock		$ 2,700
Maximum | Shelf Registration
Class Of Stock [Line Items]
Additional capital raised							$ 300,000
Certain Executive Officers Senior Management And Board Members [Member] | Private Placement
Class Of Stock [Line Items]
Private placement purchasing amount	$ 1,160
Common Stock
Class Of Stock [Line Items]
Common stock issued, shares | shares	15,166,957							6,142,158
New issuance of common stock								$ 6
Warrants to purchase common stock | shares									4,434
Common stock exercise price | $ / shares									$ 140.25
Warrant ownership limit	9.99%
Warrant ownership increase or decrease limit	19.99%
Warrant notice limit	61 days
Warrants expiration date									Oct. 30, 2025
Warrants outstanding | shares							9,689,293
Dividend distribution, number of right for each share | Right			1
Common Stock | Private Placement
Class Of Stock [Line Items]
Gross proceeds of private placement	$ 25,000
Offering costs	$ 272
Common Stock | At The Market Equity Offering Program
Class Of Stock [Line Items]
Common stock issued, shares | shares						6,100,000
Gross proceeds from issuance of common stock						$ 7,700
Offering costs						$ 595
Common Stock | Certain Executive Officers Senior Management And Board Members [Member] | Private Placement
Class Of Stock [Line Items]
Shares price, per share | $ / shares	$ 1.01
Common Stock | Pre funded warrants
Class Of Stock [Line Items]
Warrants to purchase common stock | shares							9,689,293
Common stock exercise price | $ / shares	0.001
Shares price, per share | $ / shares	$ 1.006
Common Stock | Pre funded warrants | Private Placement
Class Of Stock [Line Items]
Warrants to purchase common stock | shares	9,689,293
Shares price, per share | $ / shares	$ 1.005
Series A Preferred Stock
Class Of Stock [Line Items]
Preferred stock authorized, shares | shares						10,000,000	10,000,000	10,000,000
Preferred stock per share | $ / shares						$ 0.001	$ 0.001	$ 0.001
Preferred stock outstanding, shares | shares						0	0	0
Series A Participating Preferred Stock
Class Of Stock [Line Items]
Preferred stock per share | $ / shares			$ 0.001
Common stock exercise price | $ / shares			$ 16
Dividend distribution, each right entitled to purchase shares | shares			0.001

Equity - Schedule of Common Sto

Equity - Schedule of Common Stock Reserved for Future Issuance (Details)	Dec. 31, 2023 shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total common stock reserved for future issuance	16,476,172
Pre funded warrants
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total common stock reserved for future issuance	9,689,293
Warrants Outstanding
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total common stock reserved for future issuance	4,434
Stock Options Outstanding
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total common stock reserved for future issuance	2,645,278
Equity Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total common stock reserved for future issuance	2,570,194
Restricted Stock Units (RSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total common stock reserved for future issuance	1,055,951
Employee Stock Purchase Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total common stock reserved for future issuance	511,022

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	May 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2023	Jun. 30, 2022	Jul. 26, 2020
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Weighted average grant-date fair value of stock options granted		$ 0.66	$ 0.91
Closing stock price		$ 0.82
Stock-based compensation expense		$ 3,284	$ 4,015
Shares available for future issuance		16,476,172
Unrecognized compensation expense		$ 4,100
Weighted-average period over which unrecognized compensation expense is expected to be recognized		1 year 8 months 4 days
Stock Options
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Expiration years from the date of grant		10 years
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Service-based awards vesting percentage		6.25%
Stock awards granted		1,100,000
Aggregate fair value of restricted stock units vested		$ 186
Shares available for future issuance		1,055,951
Unrecognized compensation expense			158
Performance Stock Options and Restricted Stock Awards
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Unrecognized compensation expense		$ 500
2020 Inducement Equity Incentive Plan
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Shares reserved for future grant						500,000
Shares available for issuance		75,000
2021 Equity Incentive Plan
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Service-based awards, vesting period	4 years
Service-based awards vesting description		vest over a four-year period, with the first 25% of such awards vesting following twelve months of continued employment or service with the remaining awards vesting monthly in equal installments over the following thirty-six months
Shares available for issuance	1,000,000	2,495,194
Additional shares available for grant				2,500,000	1,500,000
2021 Equity Incentive Plan | Following Twelve Months of Service
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Service-based awards vesting percentage	25%
2021 Equity Incentive Plan | Board of Directors
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Service-based awards, vesting period	3 years	12 months
Service-based awards vesting description		vesting occurs in thirty-six equal monthly installments over a three-year period for initial grants and in twelve equal monthly installments over a twelve-month period for subsequent grants
2017 Employee Stock Purchase Plan
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 12	$ 3
Eligible employees withhold percentage of earnings to purchase shares of common stock	15%
Shares available for future issuance		511,022
Shares reserved for issuance increase percentage of total number of shares of common stock outstanding	1%
Shares Issued under plan		17,500	5,716
2017 Employee Stock Purchase Plan | Maximum
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Number of shares of common stock reserved for issuance increase on of each calendar year	300,000
2017 Employee Stock Purchase Plan | On First Date of Offering | Maximum
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Percentage of fair market value of share of common stock to purchase	85%
2017 Employee Stock Purchase Plan | On Date of Purchase | Maximum
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Percentage of fair market value of share of common stock to purchase	85%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Weighted-Average Assumptions Used to Value Stock Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Fair value of common stock	$ 0.78	$ 1.47
Risk-free interest rate	4.30%	2.31%
Dividend yield	0%	0%
Expected term of options (years)	5 years 7 months 13 days	5 years 10 months 17 days
Volatility	114.50%	68.75%
ESPP
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Fair value of common stock	$ 1.05	$ 1.32
Risk-free interest rate	5.20%	2.52%
Dividend yield	0%	0%
Expected term of options (years)	6 months	6 months 3 days
Volatility	119.32%	76.71%

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of Shares Outstanding
Outstanding, Beginning	2,363,195
Granted	345,000
Cancelled/Forfeited	(62,917)
Outstanding, Ending	2,645,278	2,363,195
Vested and expected to vest	2,645,278
Exercisable	1,332,746
Weighted-Average Exercise Price
Outstanding, Beginning	$ 9.29
Granted	0.78
Cancelled/Forfeited	5.85
Outstanding, Ending	8.26	$ 9.29
Vested and expected to vest	8.26
Exercisable	$ 12.02
Weighted-Average Remaining Contractual Term (Years)
Outstanding	7 years 2 months 1 day	8 years 2 months 19 days
Vested and expected to vest	7 years 2 months 1 day
Exercisable	7 years
Aggregate Intrinsic Value
Outstanding	$ 30	$ 65
Vested and expected to vest	30
Exercisable	$ 5

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Restricted Stock Unit Award Transactions (Details) - Restricted Stock Unit Awards	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Shares
Outstanding at December 31, 2022	162,201
Granted	1,100,000
Issued as Common Stock	(206,250)
Outstanding at December 31, 2023	1,055,951
Weighted Avg Grant Date Fair Value
Outstanding at December 31, 2022 | $ / shares	$ 3.36
Granted | $ / shares	$ 1.01
Issued as Common Stock	0.9
Outstanding at December 31, 2023 | $ / shares	$ 1.37

Stock-Based Compensation - Su_4

Stock-Based Compensation - Summary of Stock-Based Compensation Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 3,284	$ 4,015
Research and Development
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Stock-based compensation expense	1,201	1,270
General and Administrative
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 2,083	$ 2,745

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Line Items]
Current income tax expense (benefit)	$ 0	$ 0
Deferred income tax expense (benefit)	$ 0	0
Amortization period of domestic expenses capitalized	5 years
Amortization period of foreign expenses capitalized	15 years
Increase in deferred tax assets related to capitalized research expenses over year	$ 4,000,000
Valuation allowance increase (decrease), amount	$ 6,400,000	2,600,000
Cumulative change in ownership percentage	50%
Period for cumulative change in ownership	3 years
Accruals interest for uncertain tax position	$ 0	0
Penalties for uncertain tax positions	0	$ 0
Federal | Research and Development
Income Tax Disclosure [Line Items]
Tax credit carryforward	$ 447,000
Tax credit carryforward expiration year	2041
State | Research and Development
Income Tax Disclosure [Line Items]
Tax credit carryforward	$ 389,000

Income Taxes - Summary of Recon

Income Taxes - Summary of Reconciliations of Income Tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income tax expense (benefit) at federal statutory rate	$ (6,610)	$ (2,915)
Increase/(decrease) in tax resulting from:
State income taxes		(79)
Change in valuation allowance	6,541	2,628
Stock-based compensation expense	60	370
Other	$ 9	$ (4)
Income tax benefit at federal statutory rate	21%	21%
Increase/(decrease) in tax resulting from:
State income taxes	0%	0.60%
Change in valuation allowance	(20.80%)	(18.90%)
Stock-based compensation expense	(0.20%)	(2.70%)
Other	0%	0%
Total	0%	0%

Income Taxes - Components of Ne

Income Taxes - Components of Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Accrual to cash adjustment	$ 433	$ 480
Start-up costs	4,508	2,949
Patent costs	40	40
Stock-based compensation expense	1,627	1,391
Net operating loss	6,515	6,039
Capitalized R&D	4,940	978
Other Deferred Taxes	11	10
R&D Credits	528	328
Total noncurrent deferred tax assets	18,602	12,215
Valuation Allowance	$ (18,602)	$ (12,215)

Income Taxes - Summary of Net O

Income Taxes - Summary of Net Operating Losses and Tax Credit Carryforwards (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards expiration year	2041
Tax credit carryforward	$ 447
Federal | Post December 31, 2017
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	27,153
Federal | Pre January 1, 2018
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 11
Net operating loss carryforwards expiration year	2037
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 11,602
Net operating loss carryforwards expiration year	2037
Tax credit carryforward	$ 389

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Director
Related Party Transaction [Line Items]
Payments for scientific consulting services		$ 9,000
Accounts payable		0
Director One
Related Party Transaction [Line Items]
Payments for scientific consulting services		7,000
Accounts payable		$ 0
'Related party transactions	$ 0