eFFECTOR Therapeutics (EFTR) 10-Q 8 Aug 23 2023 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Jul. 31, 2023
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Entity Registrant Name	eFFECTOR Therapeutics, Inc.
Entity Central Index Key	0001828522
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		61,765,616
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity File Number	001-39866
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	85-3306396
Entity Address, Address Line One	142 North Cedros Avenue
Entity Address, Address Line Two	Suite B
Entity Address, City or Town	Solana Beach
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92075
City Area Code	858
Local Phone Number	925-8215
Document Quarterly Report	true
Document Transition Report	false
Common Stock [Member]
Document Information [Line Items]
Trading Symbol	EFTR
Title of 12(b) Security	Common stock, $0.0001 par value per share
Security Exchange Name	NASDAQ
Warrant [Member]
Document Information [Line Items]
Trading Symbol	EFTRW
Title of 12(b) Security	Warrants to purchase common stock
Security Exchange Name	NASDAQ

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 14,714	$ 8,708
Short-term investments	10,305	17,602
Prepaid expenses and other current assets	956	1,704
Total current assets	25,975	28,014
Property and equipment, net	216	241
Operating lease right-of-use assets	83	111
Other assets	615	711
Total assets	26,889	29,077
Current liabilities:
Accounts payable	1,451	1,486
Accrued expenses	1,923	3,368
Current term loans, net	19,216	19,061
Accrued final payment on term loans, current	1,100	1,100
Lease liabilities, current portion	69	60
Total current liabilities	23,759	25,075
Earn-out liability	6	6
Other accrued liabilities, non-current	484	0
Non-current warrant liability	40	40
Operating lease liabilities, non-current	25	60
Total liabilities	24,314	25,181
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.0001 par value; 100,000,000 shares authorized at June 30, 2023 and December 31, 2022; zero shares issued and outstanding as of June 30, 2023 and December 31, 2022	0	0
Common stock, $0.0001 par value; 1,000,000,000 shares authorized at June 30, 2023 and December 31, 2022; 61,765,616 shares issued and 61,465,616 shares issued and outstanding as of June 30, 2023; 41,990,383 shares issued and 41,690,383 shares issued and outstanding as of December 31, 2022	6	4
Additional paid-in capital	164,512	147,476
Accumulated other comprehensive income (loss)	1	(18)
Accumulated deficit	(161,944)	(143,566)
Total stockholders' equity	2,575	3,896
Total liabilities and stockholders' equity	$ 26,889	$ 29,077

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred Stock, Shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock price per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	61,765,616	41,990,383
Common stock, shares outstanding	61,465,616	41,690,383

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Statement [Abstract]
Grant Revenue	$ 0	$ 2,011	$ 0	$ 2,011
Operating expenses:
Research and development	4,881	6,919	11,490	10,031
General and administrative	2,974	2,973	5,901	6,409
Total operating expenses	7,855	9,892	17,391	16,440
Operating loss	(7,855)	(7,881)	(17,391)	(14,429)
Other income (expense)
Interest income	227	64	453	88
Interest expense	(722)	(505)	(1,411)	(983)
Other income (expense), net	(14)	123	(29)	(563)
Change in fair value of earn-out liability	0	1,284	0	12,041
Total other income (expense)	(509)	966	(987)	10,583
Net loss	(8,364)	(6,915)	(18,378)	(3,846)
Comprehensive loss:
Net loss	(8,364)	(6,915)	(18,378)	(3,846)
Other comprehensive income (loss)	0	(32)	19	(82)
Comprehensive loss	$ (8,364)	$ (6,947)	$ (18,359)	$ (3,928)
Net loss per share, basic	$ (0.17)	$ (0.17)	$ (0.41)	$ (0.09)
Net loss per share, diluted	$ (0.17)	$ (0.17)	$ (0.41)	$ (0.09)
Weighted-average common shares outstanding, basic	47,828,631	41,118,727	44,930,987	40,984,273
Weighted-average common shares outstanding, diluted	47,828,631	41,118,727	44,930,987	40,984,273

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2021	$ 17,284	$ 4	$ 138,181		$ (120,901)
Balance, shares at Dec. 31, 2021		40,389,975
Stock option exercises	3		3
Stock option exercises, shares		4,828
Issuance of common stock, net of issuance costs, value	3,791		3,791
Issuance of common stock, net of issuance costs, shares		700,549
Stock-based compensation expense	1,137		1,137
Unrealized loss on short-term investments	(50)			$ (50)
Net loss	3,069				3,069
Balance at Mar. 31, 2022	25,234	$ 4	143,112	(50)	(117,832)
Balance, shares at Mar. 31, 2022		41,095,352
Balance at Dec. 31, 2021	17,284	$ 4	138,181		(120,901)
Balance, shares at Dec. 31, 2021		40,389,975
Net loss	(3,846)
Balance at Jun. 30, 2022	19,623	$ 4	144,448	(82)	(124,747)
Balance, shares at Jun. 30, 2022		41,152,790
Balance at Mar. 31, 2022	25,234	$ 4	143,112	(50)	(117,832)
Balance, shares at Mar. 31, 2022		41,095,352
Issuance of common stock, net of issuance costs, value	94		94
Issuance of common stock, net of issuance costs, shares		57,438
Stock-based compensation expense	1,242		1,242
Unrealized loss on short-term investments	(32)			(32)
Net loss	(6,915)				(6,915)
Balance at Jun. 30, 2022	19,623	$ 4	144,448	(82)	(124,747)
Balance, shares at Jun. 30, 2022		41,152,790
Balance at Dec. 31, 2022	$ 3,896	$ 4	147,476	(18)	(143,566)
Balance, shares at Dec. 31, 2022	41,690,383	41,690,383
Issuance of common stock, net of issuance costs, value	$ 119		119
Issuance of common stock, net of issuance costs, shares		410,836
Stock-based compensation expense	1,167		1,167
Unrealized loss on short-term investments	19			19
Net loss	(10,014)				(10,014)
Balance at Mar. 31, 2023	(4,813)	$ 4	148,762	1	(153,580)
Balance, shares at Mar. 31, 2023		42,101,219
Balance at Dec. 31, 2022	$ 3,896	$ 4	147,476	(18)	(143,566)
Balance, shares at Dec. 31, 2022	41,690,383	41,690,383
Stock option exercises, shares	56,008
Net loss	$ (18,378)
Balance at Jun. 30, 2023	$ 2,575	$ 6	164,512	1	(161,944)
Balance, shares at Jun. 30, 2023	61,465,616	61,465,616
Balance at Mar. 31, 2023	$ (4,813)	$ 4	148,762	1	(153,580)
Balance, shares at Mar. 31, 2023		42,101,219
Stock option exercises	29		29
Stock option exercises, shares		56,008
Issuance of common stock, net of issuance costs - Registered direct offerings	14,539	$ 1	14,538
Issuance of common stock, net of issuance costs - Registered direct offerings, Shares		10,650,000
Exercise of prefunded warrants - Registered direct offerings, Shares		8,564,827
Exercise of prefunded warrants - Registered direct offerings, value	9	$ 1	8
Issuance of common stock, net of issuance costs, value	13		13
Issuance of common stock, net of issuance costs, shares		93,562
Stock-based compensation expense	1,162		1,162
Net loss	(8,364)				(8,364)
Balance at Jun. 30, 2023	$ 2,575	$ 6	$ 164,512	$ 1	$ (161,944)
Balance, shares at Jun. 30, 2023	61,465,616	61,465,616

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating activities:
Net loss	$ (18,378)	$ (3,846)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation and amortization expense	55	8
Accretion of discount and amortization of premium on investments, net	(197)	122
Stock-based compensation	2,329	2,379
Gain on change in fair value of warrant liability	0	(598)
Gain on change in fair value of earn-out liability	0	(12,041)
Other expense related to equity purchase agreement	29	1,161
Non-cash interest expense	155	188
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	766	2,032
Other non-current assets	96	96
Accounts payable	(60)	662
Accrued expenses	(1,027)	(1,096)
Operating lease right-of-use assets and liabilities, net	3	(2)
Net cash used in operating activities	(16,229)	(10,935)
Investing activities:
Purchases of fixed assets	(41)	(134)
Maturities of short-term investments	20,750	10,000
Purchases of short-term investments	(13,256)	(34,971)
Net cash provided by (used in) investing activities	7,453	(25,105)
Financing activities:
Payment of debt issuance costs	0	(37)
Proceeds from exercise of common stock options and warrants	38	3
Proceeds from issuance of common stock - Registered direct offerings, net of issuance costs	14,642	0
Proceeds from issuance of common stock including ESPP, net of issuance costs	102	2,725
Net cash provided by financing activities	14,782	2,691
Net increase (decrease) in cash and cash equivalents	6,006	(33,349)
Cash and cash equivalents at beginning of period	8,708	49,702
Cash and cash equivalents at end of period	14,714	16,353
Supplemental disclosure of cash flow information:
Interest paid	1,221	824
Supplemental disclosure of non-cash investing and financing activities:
Issuance of commitment shares	0	862
Accrued issuance costs	103	0
Purchases of fixed assets included in accounts payable and accrued expenses	$ 1	$ 26

Organization and Basis of Prese

Organization and Basis of Presentation	6 Months Ended
	Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	1. Organization and Basis of Presentation Description of Business Locust Walk Acquisition Corp. ("LWAC”) was initially formed on October 2, 2020 as a Delaware corporation formed for the purpose of effecting a merger, capital stock exchange, asset acquisition, stock purchase, reorganization or other similar business transaction with one or more operating businesses. On May 26, 2021, LWAC entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Locust Walk Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of LWAC (“Merger Sub”), and eFFECTOR Therapeutics, Inc., a Delaware corporation (“Old eFFECTOR”). Pursuant to the terms of the Merger Agreement, a business combination between LWAC and Old eFFECTOR was effected through the merger of the Merger Sub with and into Old eFFECTOR, with Old eFFECTOR becoming the surviving company and a wholly-owned subsidiary of LWAC with the name of eFFECTOR Therapeutics Operations, Inc. On August 25, 2021, and in connection with the closing of the business combination (the "Business Combination"), LWAC was renamed eFFECTOR Therapeutics, Inc. ("eFFECTOR" or the "Company"). All outstanding preferred shares of Old eFFECTOR converted into common shares of Old eFFECTOR on a 1:1 basis, which were then converted, along with all outstanding common shares of Old eFFECTOR, into common shares of the surviving eFFECTOR company through application of an exchange ratio of approximately 0.09657 . The Company is a clinical-stage biopharmaceutical company focused on pioneering the development of a new class of oncology drugs the Company refers to as selective translation regulator inhibitors ("STRIs"). The Company’s principal operations are in the United States, with its headquarters in Solana Beach, California. The Company has devoted substantially all of its resources to raising capital, identifying potential product candidates, establishing its intellectual property portfolio, conducting preclinical studies and clinical trials, establishing arrangements with third parties for the manufacture of its product candidates and related raw materials, and providing general and administrative support for these operations. The Company has not generated revenues from its principal operations, other than from licensing and grant revenue, through June 30, 2023. Basis of Presentation The accompanying unaudited condensed consolidated financial statements as of June 30, 2023 and for the three and six months ended June 30, 2023 and 2022 have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and pursuant to Article 10 of Regulation S-X of the Securities Act of 1933, as amended (the “Securities Act”). Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. These unaudited financial statements include only normal and recurring adjustments that the Company believes are necessary to fairly state the Company’s financial position and the results of its operations and cash flows. The results for the three and six months ended June 30, 2023 are not necessarily indicative of the results expected for the full fiscal year or any subsequent interim period. The balance sheet at December 31, 2022 has been derived from the audited financial statements at that date but does not include all the disclosures required by GAAP for complete financial statements. Because all of the disclosures required by GAAP for complete financial statements are not included herein, these unaudited financial statements and the notes accompanying them should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2022 included in its Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 8, 2023. Liquidity The Company has a limited operating history and the sales and income potential of the Company’s business and market are unproven. The accompanying financial statements have been prepared assuming the Company will continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or amounts and classification of liabilities that may result from the outcome of this uncertainty. Management is required to perform a two-step analysis over its ability to continue as a going concern. Management must first evaluate whether there are conditions and events that raise substantial doubt about the Company’s ability to continue as a going concern (step 1). If management concludes that substantial doubt is raised, management is also required to consider whether its plans alleviate that doubt (step 2). The Company has experienced net losses and negative cash flows from operating activities since its inception, aside from the years ended December 31, 2021 and December 31, 2020 when net income was realized as a result of a gain in fair value recognized associated with the earn-out liability and revenue in connection with the Research Collaboration and License Agreement with Pfizer, respectively. The Company has an accumulated deficit of $ 161.9 million at June 30, 2023. For the six months ended June 30, 2023, the Company used $ 16.2 million in cash for operations. At June 30, 2023, the Company had cash and cash equivalents and short-term investments of $ 25.0 million. The Company anticipates that its expenses will increase significantly in connection with its ongoing activities to support its research and development efforts, and it expects to incur substantial operating losses and negative cash flows from operations for the foreseeable future. Management has prepared cash flow forecasts which indicate that based on the Company’s expected operating losses and negative cash flows, there is substantial doubt about the Company’s ability to continue as a going concern within twelve months from the date that these financial statements for the three and six months ended June 30, 2023 are issued. The principal payments due under the Oxford Loans (as defined below), and the related accrued final payment, have been classified as current liabilities as of June 30, 2023, due to the considerations discussed above and the assessment that the material adverse change clause under the Oxford Loans is not within the Company’s control. The Company has not been notified of an event of default by the lender as of the date of issuance of these financial statements. The Company’s ability to continue as a going concern is dependent upon its ability to receive additional capital. Management intends to raise additional capital through equity offerings or other capital sources, including potential additional collaborations, licenses and other similar arrangements. Additionally, the Company may receive additional milestone payments from the Research Collaboration and License Agreement with Pfizer (described in Note 12), through the issuance of common stock under the equity purchase agreement (the "Purchase Agreement") with Lincoln Park Capital Fund, LLC ("Lincoln Park") (described in Note 9) or through the issuance of common stock under the at-the-market offering program (described in Note 9) with Cantor Fitzgerald & Co ("Cantor"). However, the Company may not be able to secure additional financing in a timely manner or on favorable terms, if at all, and may not receive any milestone payments. Without additional capital, the Company may be forced to delay, scale back or eliminate some of its research and development activities, or other operations and potentially delay product development in an effort to provide sufficient funds to continue its operations, or may be required to pursue merger or acquisition strategies, all of which could adversely affect the holdings or the rights of its stockholders.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Research and Development Costs Research and development expenses primarily consist of costs associated with the preclinical and clinical development of the Company’s product candidates. Research and development costs are expensed as incurred. Clinical Trial Accruals and Preclinical Studies The Company records expenses resulting from our obligations under contracts with vendors and consultants, CROs and clinical sites in connection with conducting clinical trials and preclinical studies. The financial terms of these contracts are subject to negotiations which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company reflects clinical trial and preclinical study expenses in the financial statements by matching those expenses with the period in which services and efforts are expended. The Company accounts for these expenses according to the progress of the clinical trial or preclinical study as measured by the timing of various aspects of the clinical trial, preclinical study, or related activities. The Company determines accrual estimates based on the underlying contracts, correspondence with clinical and other key personnel and third-party service providers as to the progress of the clinical trials, preclinical studies, or other services being conducted, and amounts invoiced or paid to date. During the course of a clinical trial or preclinical study, the Company adjusts the rate of expense recognition if actual results differ from estimates. Public and Private Placement Warrants Upon completion of the Business Combination, the Company assumed public and private placement warrants that were issued by LWAC in connection with their initial public offering in January 2021 whereby holders of the public and private placement warrants are entitled to acquire common stock of the Company. The Company has concluded that the public warrants are equity-classified. Because the settlement value of the private placement warrants is dependent, in part, on who holds the warrants at the time of settlement, they are not considered indexed to the Company's stock and are therefore recorded as liabilities. Warrants classified as liabilities are recorded at their estimated fair value on the date of issuance and are revalued at each subsequent balance sheet date, with fair value changes recognized in other income (expense), net in the accompanying consolidated statements of operations and comprehensive loss. The Company estimates the fair value of these warrants using the Black-Scholes option pricing model. Stock-Based Compensation Expense Stock-based compensation expense represents the cost of the grant date fair value of employee stock option grants recognized over the requisite service period of the awards (usually the vesting period) on a straight- line basis. The Company estimates the fair value of stock option grants using the Black-Scholes option-pricing model. The Company accounts for stock options granted to non-employees using the fair value approach. The Black-Scholes option-pricing model requires the use of subjective assumptions, including the risk-free interest rate, the expected stock price volatility, the expected term of stock options, and the expected dividend yield. The Company has limited historical stock option activity and therefore estimates the expected term of stock options granted using the simplified method, which represents the average of the contractual term of the stock option and its weighted-average vesting period. The fair value of the underlying common stock used within the Black-Scholes option-pricing model is based on the closing price of common stock on the date of grant. Earn-Out Shares In accordance with the Merger Agreement, 5,000,000 shares ("Earn-Out Shares") are contingently issuable to Old eFFECTOR stockholders and option holders upon the occurrence of the Triggering Event, defined within the Merger Agreement as the date on which the common stock price equals or exceeds $ 20.00 over at least 20 trading days out of a 30 consecutive trading day period during the two-year period following the close date of the Business Combination. The estimated fair value of the Earn-Out Shares was determined using a Monte Carlo simulation valuation model using a distribution of potential outcomes on a monthly basis over the earn-out period using the most reliable information available. The Company has determined that the contingent obligation to issue Earn-Out Shares to existing Old eFFECTOR shareholders is not indexed to the Company's stock under Accounting Standards Codification ("ASC") 815-40 and therefore equity treatment is precluded. The Triggering Event that determines the issuance of the Earn-Out Shares includes terms that are not solely indexed to our common stock, and as such liability classification is required. Equity-linked instruments classified as liabilities are recorded at their estimated fair value on the date of issuance and are revalued at each subsequent balance sheet date, with fair value changes recognized in other income (expense), net in the accompanying consolidated statements of operations and comprehensive loss. The Company has determined that the contingent obligation to issue Earn-Out Shares to existing Old eFFECTOR option holders falls within the scope of ASC 718, Share-based Compensation, because the option holders are required to continue providing service until the occurrence of the Triggering Event. The fair value of the option holder Earn-Out Shares is recorded as share-based compensation over the derived service period of the Monte Carlo simulation valuation model, recognized in research and development and general and administrative expense in the consolidated statements of operations and comprehensive loss. Comprehensive Loss Comprehensive loss consists of net loss and unrealized gains or losses on available-for-sale investments. The Company presents comprehensive loss and its components as part of the consolidated statements of operations and comprehensive loss. Cash, Cash Equivalents and Short-term Investments Cash and Cash Equivalents The Company considers all highly liquid investments with insignificant interest rate risk and an original maturity of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents consist of money market funds and U.S. Treasury securities with an original maturity of three months or less at the date of purchase. Short-term Investments Short-term investments consist of U.S. Treasury securities, classified as available-for-sale securities and have maturities of greater than three months but less than one year. The Company has classified all of its available-for-sale securities as current assets on the balance sheets because these are considered highly liquid securities and are available for use in current operations. The Company carries these securities at fair value and reports unrealized gains and losses as a separate component of accumulated other comprehensive income (loss). Amortization and accretion of any purchase premiums or discounts is included in interest income in the consolidated statements of operations and comprehensive loss. Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board ("FASB") or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes, based on its preliminary assessment, that the impact of recently issued standards that are not yet effective will not have a material impact on their financial position or results of operations upon adoption. Net Income (Loss) Per Share The Company computes net income (loss) per share in accordance with the FASB guidance for Earnings Per Share, which established standards regarding the computation of earnings per share by companies that have issued securities other than common stock that contractually entitle the holder to participate in earnings and dividends. The guidance requires earnings available to common shareholders for the period, after deduction of preferred stock preferences, to be allocated between the common and preferred shareholders based on their respective rights to receive dividends. Basic net income (loss) per share is calculated by dividing income (loss) allocable to common shareholders by the weighted-average number of common shares outstanding, during the period. The Company calculates diluted net income per share using the more dilutive of the 1) treasury stock method, if-converted method, or contingently issuable share method, as applicable, or 2) the two-class method. Due to the Company recording net loss for the three and six months ended June 30, 2023 and 2022 and none of the outstanding securities being dilutive for those periods, basic and diluted loss per share are the same for each respective period presented. Potentially dilutive s ecurities as of June 30, 2023 and 2022 are as follows (in common stock equivalent shares): As of June 30, 2023 2022 Common stock warrants 19,214,827 — Placement agent warrants 1,345,038 — Public warrants 5,833,323 5,833,323 Private placement warrants 181,667 181,667 Earn-Out Shares 5,000,000 5,000,000 Unvested sponsor shares 300,000 300,000 Stock options outstanding 11,678,262 8,102,034 Total 43,553,117 19,417,024

Business Combination

Business Combination	6 Months Ended
	Jun. 30, 2023
Business Combinations [Abstract]
Business Combination	3. Business Combination As discussed in Note 1, on August 25, 2021, the Company completed the Business Combination pursuant to the Merger Agreement. Upon closing of the Business Combination, the combined company was renamed eFFECTOR Therapeutics, Inc. In connection with the closing of the Business Combination, the LWAC sponsor received 4,056,250 shares of eFFECTOR common stock, of which 300,000 shares were subject to vesting if, on or prior to August 25, 2024, the price of shares of common stock equals or exceeds $ 15.00 per share for a period of at least 20 trading days out of 30 consecutive trading days ending on the trading day immediately prior to the date of determination (the "Sponsor Shares"). The 300,000 Sponsor Shares subject to vesting meet the criteria for equity classification, but are not considered outstanding from an accounting perspective. These shares are considered issued but not outstanding as of June 30, 2023 and June 30, 2022, and have been excluded from outstanding shares in the calculation of loss per share for the three and six months ended June 30, 2023 and 2022.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. Fair Value Measurements The accounting guidance defines fair value, establishes a consistent framework for measuring fair value and expands disclosure for each major asset and liability category measured at fair value on either a recurring or nonrecurring basis. Fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the accounting guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. Level 2: Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability. Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e. supported by little or no market activity). The Company’s cash equivalents are classified using Level 1 inputs within the fair value hierarchy because they are valued using quoted market prices, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency. None of the Company’s non-financial assets or liabilities are recorded at fair value on a non-recurring basis. No transfers between levels have occurred during the periods presented. The Company estimates the fair value of its warrant liabilities at the time of issuance and subsequent remeasurement using the Black-Scholes option pricing model at each reporting date, if required, based on the following inputs: the risk-free interest rates; the expected dividend rates; the remaining contractual life of the warrants; the fair value of the underlying stock; and the expected volatility of the price of the underlying stock. The estimates are based, in part, on subjective assumptions and could differ materially in the future. Changes to these assumptions as well as the fair value of the Company’s stock on the reporting date can have a significant impact on the fair value of the warrant liability. The following table summarizes the Company’s assets and liabilities that require fair value measurements on a recurring basis and their respective input levels based on the fair value hierarchy as of June 30, 2023 and December 31, 2022 (in thousands): Fair Value Measurements Using June 30, Quoted Prices Significant Significant 2023 Level 1 Level 2 Level 3 Assets Cash equivalents: Money market funds $ 12,731 $ 12,731 $ — $ — U.S. Treasury securities 1,983 — 1,983 — Short-term investments: U.S. Treasury securities 10,305 — 10,305 — Total assets $ 25,019 $ 12,731 $ 12,288 $ — Liabilities Private placement warrant liability $ 40 $ — $ — $ 40 Earn-out liability 6 — — 6 Total liabilities $ 46 $ — $ — $ 46 Fair Value Measurements Using December 31, Quoted Prices Significant Significant 2022 Level 1 Level 2 Level 3 Assets Cash equivalents: Money market funds $ 8,708 $ 8,708 $ — $ — Short-term investments: U.S. Treasury securities 17,602 — 17,602 — Total assets $ 26,310 $ 8,708 $ 17,602 $ — Liabilities Private placement warrant liability $ 40 $ — $ — $ 40 Earn-out liability 6 — — 6 Total liabilities $ 46 $ — $ — $ 46 Cash Equivalents and Short-Term Investments Financial assets measured at fair value on a recurring basis consist of the Company’s cash equivalents and short-term investments. Cash equivalents consisted of money market funds and U.S. Treasury securities with an original maturity of less than three months at the date of purchase and short-term investments consisted of U.S. Treasury securities with an original maturity of more than three months at the date of purchase. The Company obtains pricing information from its investment manager and generally determines the fair value of investment securities using standard observable inputs, including reported trades, broker/dealer quotes, and bids and/or offers. Investments are classified as Level 1 within the fair value hierarchy if their quoted prices are available in active markets for identical securities. Investments in money market funds of $ 12.7 million and $ 8.7 million as of June 30, 2023 and December 31, 2022, respectively, were classified as Level 1 instruments and were included in cash and cash equivalents. Investments in marketable securities are valued using Level 2 inputs. Level 2 securities are initially valued at the transaction price and subsequently valued and reported upon utilizing inputs other than quoted prices that are observable either directly or indirectly, such as quotes from third-party pricing vendors. Fair values determined by Level 2 inputs, which utilize data points that are observable such as quoted prices, interest rates and yield curves, require the exercise of judgment and use of estimates, that if changed, could significantly affect the Company’s financial position and results of operations. The marketable securities of $ 12.3 million as of June 30, 2023 were classified as Level 2 instruments, $ 2.0 million of which is included in cash and cash equivalents and $ 10.3 million of which is included in short-term investments. The marketable securities of $ 17.6 million as of December 31, 2022 were classified as Level 2 instruments, all of which are included in short-term investments. Accrued interest receivable related to short-term investments was $ 72,000 and $ 27,000 as of June 30, 2023 and December 31, 2022, respectively, and included as part of prepaid expenses and other current assets in the condensed balance sheets. The following tables summarize the Company’s short-term investments accounted for as available-for-sale securities as of June 30, 2023 and December 31, 2022 (in thousands): June 30, 2023 Maturity Amortized Unrealized Unrealized Estimated (in years) Cost Gains Losses Fair Value U.S. Treasury securities 1 year or less $ 12,287 $ 2 $ ( 1 ) $ 12,288 $ 12,287 $ 2 $ ( 1 ) $ 12,288 December 31, 2022 Maturity Amortized Unrealized Unrealized Estimated (in years) Cost Gains Losses Fair Value U.S. Treasury securities 1 year or less $ 17,620 $ 1 $ ( 19 ) $ 17,602 $ 17,620 $ 1 $ ( 19 ) $ 17,602 Private Placement Warrant Liability In connection with the Business Combination, the Company assumed the public and private placement warrants described in Note 2. The private placement warrants are precluded from equity treatment and are recorded as liabilities as they are not considered indexed to the Company's common stock. The private placement warrant liability is measured at fair value, using a combination of observable and unobservable inputs. The change in fair value of the private placement warrant liability is recorded in other income (expense) on the statement of operations and comprehensive loss. The following key assumptions were used in determining the fair value of the private placement warrant liability valued using the Black-Scholes option pricing model as of June 30, 2023 and December 31, 2022: June 30, December 31, Common stock price $ 0.83 $ 0.43 Expected volatility 125.0 % 125.0 % Risk-free interest rate 4.5 % 4.2 % Expected term (in years) 3.2 3.7 Expected dividend yield — — The following table presents activity for the private placement warrant liability measured at fair value using significant unobservable Level 3 inputs during the six months ended June 30, 2023 (in thousands): Private Placement Warrant Liability Balance at December 31, 2022 $ 40 Change in fair value — Balance at June 30, 2023 $ 40 Earn-Out Liability Former holders of shares of Old eFFECTOR common stock were allocated Earn-Out Shares in connection with the completion of the Business Combination with LWAC which are accounted for as liabilities. Please refer to Note 10 f or additional details surrounding the valuation methodology for these Earn-Out Shares.

Property and Equipment , net

Property and Equipment , net	6 Months Ended
	Jun. 30, 2023
Property, Plant and Equipment [Abstract]
Property and Equipment , net	5. Property and Equipment, net Property and equipment, net consists of the following (in thousands): June 30, December 31, Lab equipment $ 30 $ 30 Computer and office equipment 154 149 Furniture and fixtures 78 61 Leasehold improvements 188 188 Construction in process 37 29 487 457 Less accumulated depreciation and amortization ( 271 ) ( 216 ) $ 216 $ 241 The Company recorded depreciation and amortization expense of approximately $ 27,000 and $ 3,000 for the three months ended June 30, 2023 and 2022, respectively, and approximately $ 55,000 and $ 8,000 for the six months ended June 30, 2023 and 2022, respectively.

Accrued Expenses

Accrued Expenses	6 Months Ended
	Jun. 30, 2023
Payables and Accruals [Abstract]
Accrued Expenses	6. Accrued Expenses Accrued expenses consist of the following (in thousands): June 30, December 31, Employee compensation $ 946 $ 1,385 Research and development 465 1,206 Professional and outside services 298 112 Interest 212 197 Other 2 468 $ 1,923 $ 3,368

Term Loans

Term Loans	6 Months Ended
	Jun. 30, 2023
Notes and Loans Payable, by Type, Current and Noncurrent [Abstract]
Term Loans	7. Term Loans Oxford Term Loans In March 2021, Old eFFECTOR entered into a Loan and Security Agreement (“Oxford LSA”) with Oxford Finance LLC (“Oxford”), pursuant to which the Company may borrow up to $ 30.0 million, issuable in two separate tranches of $ 20.0 million (“Term A Loans”) and $ 10.0 million (“Term B Loans”), collectively referred to as the Oxford Loans. The Term A Loans became available to the Company at the effective date of the Oxford LSA on March 19, 2021 and $ 12.5 million of the proceeds were used to pay off the previously outstanding Silicon Valley Bank term loans. The remaining net proceeds from Term A Loans of $ 7.4 million, after taking into effect specified issuance and legal fees designated within the distribution letter, were distributed to the Company in March 2021. The Company is required to make a final payment equal to 5.5 % of each funded tranche at maturity, which has been recorded as a debt discount for the Term A Loans and is being amortized over the term of the debt arrangements. In connection with the Oxford LSA, the Company issued warrants to purchase a total of 37,575 shares of Series C Preferred Stock at an exercise price of $ 5.33 per share. The warrants were automatically exercised on a cashless basis on August 25, 2021, in connection with the completion of the Business Combination, for 17,575 shares of common stock. On February 22, 2022, the Company entered into an amendment to the Oxford LSA whereby the interest only period for the Term A Loans will end on March 1, 2024 , instead of May 1, 2023. In connection with the amendment, the maturity of the Term A Loans was extended from March 18, 2026 to February 1, 2027. Additionally, Term B Loans would have become available to the Company after January 1, 2023 upon achievement of certain clinical development milestones, until the earlier of (i) June 30, 2023 , (ii) 45 days after the achievement of certain clinical development milestones, and (iii) the occurrence of an event of default. As the Company did not achieve the clinical development milestones by June 30, 2023, it no longer has access to the additional $ 10.0 million under the Term B Loans. The Oxford Loans carry a variable interest rate equal to the greater of (i) 7.7 % and (ii) the sum of the prime rate plus 4.45 %. The Company has the option to prepay all, but not less than all, of the borrowed amounts, provided that the Company will be obligated to pay a prepayment fee equal to (i) 3.0 % of the outstanding principal balance of the applicable Oxford Loans if prepayment is made prior to the first anniversary of the effective date of the Oxford LSA, (ii) 2.0 % of the outstanding principal balance of the applicable Oxford Loans if prepayment is made after the first anniversary of the effective date of the Oxford LSA but before the second anniversary, and (iii) 1.0 % of the outstanding principal balance of the applicable Oxford Loans if prepayment is made after the second anniversary of the effective date of the Oxford LSA but before the third anniversary. No prepayment fee will apply for a prepayment made after the third anniversary of the effective date of the Oxford LSA and prior to the maturity date. The Company’s obligations under the Oxford LSA are secured by a first priority security interest in substantially all of its current and future assets, other than its owned intellectual property. The Company is also obligated to comply with various other customary covenants, including restrictions on its ability to encumber intellectual property assets without consent. The Company recorded a debt discount of $ 1.6 million for the estimated fair value of warrants, debt issuance costs, and final payment to be made, which is being amortized to interest expense over the term of the loan using the effective-interest method. As of June 30, 2023 and December 31, 2022 , the Company had $ 20.0 million of outstanding principal under the Term A Loans of which $ 19.2 million is reflected on the balance sheet net of debt discounts. Interest expense, including amortization of debt discount related to the Oxford Term A Loans, totaled $ 0.7 million and $ 1.4 million for the three and six months ended June 30, 2023, respectively, and $ 0.5 million and $ 1.0 million for the three and six months ended June 30, 2022, respectively. The Company is in compliance with all covenants under the Oxford LSA as of June 30, 2023. The Term A Loans include customary events of default, including instances of a material adverse change in our operations, that may require prepayment of the outstanding Term A Loans. The principal payments due under the Oxford Loans, and the related accrued final payment, have been classified as current liabilities as of June 30, 2023, due to the considerations discussed in the Liquidity section of Note 1. The Company has not been notified of an event of default by the lender as of the date of issuance of these financial statements. Based on the outstanding principal amounts for the Company’s Term A Loans, the following table sets forth by year the Company’s required future principal payments as of June 30, 2023 (in thousands): As of June 30, 2023 2024 $ 5,555 2025 6,667 2026 6,667 2027 1,111 Required future principal payments $ 20,000 Unamortized debt discount ( 784 ) Current term loans, net as of June 30, 2023 $ 19,216

Warrants

Warrants	6 Months Ended
	Jun. 30, 2023
Warrants and Rights Note Disclosure [Abstract]
Warrants	8. Warrants Assumed Public Warrants and Private Placement Warrants Following the consummation of the Business Combination, holders of the public warrants and private placement warrants are entitled to acquire common stock of the Company. The warrants became exercisable on January 12, 2022, which is 12 months from the closing of the LWAC's initial public offering. Each warrant entitles the registered holder to purchase one share of common stock at an exercise price of $ 11.50 per share. The public warrants and private placement warrants will expire on August 25, 2026 , which is five years after the completion of the Business Combination. Once the public warrants and private placement warrants became exercisable, the Company has the right to redeem the outstanding warrants in whole and not in part at a price of $ 0.01 per warrant upon a minimum of 30 days’ prior written notice of redemption, if and only if the last sale price of the common stock equals or exceeds $ 18.00 per share for any 20 trading days within a 30 -trading day period ending on the third trading day prior to the date on which the Company sends the notice of redemption to the warrant holders. The private placement warrants are identical to the public warrants except that, so long as they are held by the Sponsor or its permitted transferees: (i) they will not be redeemable by the Company; (ii) they may be exercised by the holders on a cashless basis; and (iii) they are subject to registration rights. Private placement warrants are liability-classified (See Note 4) and the public warrants are equity-classified. The following table summarizes the number of outstanding public warrants and private placement warrants and the corresponding exercise price as of June 30, 2023 and December 31, 2022: June 30, December 31, Exercise Price Expiration Date Public warrants 5,833,323 5,833,323 $ 11.50 August 24, 2026 Private placement warrants 181,667 181,667 $ 11.50 August 24, 2026 Warrants - 2023 Registered Direct Offerings In May 2023, the Company completed a registered direct offering (“May 2023 Registered Direct Offering”) which included the issuance of 6,750,382 shares of common stock in the form of pre-funded warrants with a purchase price of $ 0.654 per share and an exercise price of $ 0.001 (the “May 2023 Pre-Funded Warrants”). The May 2023 Pre-Funded Warrants were immediately exercised. Additionally, in a concurrent private placement, the Company issued warrants to purchase up to 11,450,382 shares of common stock (the “May 2023 Common Stock Warrants”) with an exercise price of $ 0.53 per share. The May 2023 Common Stock Warrants will expire on November 30, 2028 , which is five and one-half years from the issuance date. Further, the Company issued warrants to designees of the placement agent to purchase up to 801,527 shares of common stock ("May 2023 Placement Agent Warrants") with an exercise price of $ 0.8188 per share. The May 2023 Placement Agent Warrants will expire on May 26, 2028 , which is five years following the commencement of sales in the May 2023 Registered Direct Offering. See Note 9 for additional detail surrounding the May 2023 Registered Direct Offering. In June 2023, the Company completed a registered direct offering (“June 2023 Registered Direct Offering”) which included the issuance of 1,814,445 shares of common stock in the form of pre-funded warrants with a purchase price of $ 1.124 per share and an exercise price of $ 0.001 (the “June 2023 Pre-Funded Warrants”). The June 2023 Pre-Funded Warrants were immediately exercised. Additionally, in a concurrent private placement, the Company issued warrants to purchase up to 7,764,445 shares of common stock (the “June 2023 Common Stock Warrants”) with an exercise price of $ 1.00 per share. The June 2023 Common Stock Warrants will expire on December 8, 2028 , which is five and one-half years from the issuance date. Further, the Company issued warrants to designees of the placement agent to purchase up to 543,511 shares of common stock ("June 2023 Placement Agent Warrants") with an exercise price of $ 1.4063 per share. The June 2023 Placement Agent Warrants will expire on June 6, 2028 , which is five years following the commencement of sales in the June 2023 Registered Direct Offering. See Note 9 for additional detail surrounding the June 2023 Registered Direct Offering. The common stock warrants and placement agent warrants are equity-classified. The following table summarizes the number of outstanding common stock warrants and placement agent warrants and the corresponding exercise price as of June 30, 2023 and December 31, 2022: June 30, December 31, Exercise Price Expiration Date May 2023 Common Stock Warrants 11,450,382 — $ 0.53 November 30, 2028 May 2023 Placement Agent Warrants 801,527 — $ 0.8188 May 26, 2028 June 2023 Common Stock Warrants 7,764,445 — $ 1.00 December 8, 2028 June 2023 Placement Agent Warrants 543,511 — $ 1.4063 June 6, 2028

Preferred Stock and Stockholder

Preferred Stock and Stockholders' Deficit	6 Months Ended
	Jun. 30, 2023
Equity [Abstract]
Preferred Stock and Stockholders' Deficit	9. Preferred Stock and Stockholders’ Equity Purchase Agreement On January 24, 2022, the Company entered into the Purchase Agreement and a registration rights agreement with Lincoln Park which provides for the sale to Lincoln Park up to $ 50.0 million of shares (the “Purchase Shares”) of the Company's common stock over the thirty-six ( 36 ) month term of the Purchase Agreement. In connection with the Purchase Agreement, Lincoln Park made an initial purchase of $ 3.0 million of shares of common stock, which equated to 557,610 shares of common stock, and the Company issued 142,939 shares of common stock to Lincoln Park as a commitment fee in connection with entering into the Purchase Agreement. The Company recognized $ 0.8 million of other expense relating to the commitment fee share issuance. As of June 30, 2023 , a total of 30,000 shares of common stock have been sold in addition to the upfront amount, with such shares sold during the three months ended June 30, 2022. There were no purchases under the Purchase Agreement during the three and six months ended June 30, 2023. Under the Purchase Agreement, the Company has sole discretion, subject to certain conditions, on any business day selected by the Company to require Lincoln Park to purchase up to 30,000 shares of common stock (the “Regular Purchase Amount”) at the Purchase Price (as defined below) per purchase notice (each such purchase, a “Regular Purchase”). The Regular Purchase Amount may be increased as follows: to up to 50,000 shares if the closing price is not below $5.00, and up to 75,000 shares if the closing price is not below $10.00. Lincoln Park’s committed obligation under each Regular Purchase is capped at $ 2,500,000 , unless the Parties agree otherwise. The purchase price for Regular Purchases (the “Purchase Price”) shall be equal to the lesser of: (i) the lowest sale price of the common shares during the Purchase Date (as defined in the Purchase Agreement), or (ii) the average of the three (3) lowest closing sale prices of the common shares during the ten (10) business days prior to the Purchase Date. In addition to Regular Purchases and subject to certain conditions and limitations, the Company in its sole discretion may require Lincoln Park on each Purchase Date to purchase on the following business day up to the lesser of (i) three (3) times the number of shares purchased pursuant to such Regular Purchase or (ii) 25 % of the trading volume on the Accelerated Purchase Date (as defined in the Purchase Agreement) (the “Accelerated Purchase”) (unless the Parties agree otherwise) at a purchase price equal to the lesser of 97 % of (i) the closing sale price on the Accelerated Purchase Date, or (ii) the Accelerated Purchase Date’s volume weighted average price (the “Accelerated Purchase Price”). The Company has the sole right to set a minimum price threshold for each Accelerated Purchase in the notice provided with respect to such Accelerated Purchase and under certain circumstances and in accordance with the Purchase Agreement the Company may direct multiple Accelerated Purchases in a day. The aggregate number of shares that the Company can sell to Lincoln Park under the Purchase Agreement may not exceed 8,133,926 shares of the Common Shares (which is equal to approximately 19.99 % of the shares of the Common Shares outstanding immediately prior to the execution of the Purchase Agreement) (the “Exchange Cap”), unless (i) shareholder approval is obtained to issue Purchase Shares above the Exchange Cap, in which the Exchange Cap will no longer apply, or (ii) the average price of all applicable sales of Common Shares to Lincoln Park under the Purchase Agreement equals or exceeds $ 6.42 per share; provided that at no time may Lincoln Park (together with its affiliates) beneficially own more than 4.99 % of the Company’s issued and outstanding Common Shares. The Purchase Agreement contains customary representations, warranties, covenants, closing conditions, indemnification and termination provisions. The Purchase Agreement may be terminated by the Company at any time, at its sole discretion, without any cost or penalty, by giving one business day notice to Lincoln Park. Further, Lincoln Park has covenanted not to engage in any direct or indirect short selling or hedging of the Common Shares. There are no limitations on the use of proceeds, financial or business covenants, restrictions on future financings (other than restrictions on the Company’s ability to enter into a similar type of agreement or Equity Line of Credit during the Term, excluding an At-The-Market transaction with a registered broker-dealer), rights of first refusal, participation rights, penalties or liquidated damages in the Purchase Agreement. At-the-Market Offering Program In September 2022, the Company entered into a Controlled Equity Offering Sales Agreement (the "Sales Agreement") with Cantor, under which the Company may, from time to time, sell shares of the Company’s common stock having an aggregate offering price of up to $ 15.0 million in “at the market” offerings (the "ATM Offering Program") through Cantor. Sales of the shares of common stock will be made at prevailing market prices at the time of sale, or as otherwise agreed with Cantor. Cantor will receive a commission from the Company of 3.0 % of the gross proceeds of any shares of common stock sold under the Sales Agreement. During the six months ended June 30, 2023, the Company sold an aggregate of 410,836 shares of common stock at a weighted-average price of $ 0.56 per share for gross proceeds of approximately $ 0.2 million under the ATM Offering Program. Offering costs, including commissions, of approximately $ 0.1 million were recorded as an offset to gross proceeds within additional paid-in capital. 2023 Registered Direct Offerings The May 2023 Registered Direct Offering included the issuance and sale of an aggregate of 4,700,000 shares of the Company’s common stock at a purchase price of $ 0.655 per share in a registered direct offering priced at-the-market under Nasdaq rules. In addition, the offering included the issuance of the May 2023 Pre-Funded Warrants, which were immediately exercised, and the May 2023 Common Stock Warrants. The Company received gross proceeds from the May 2023 Registered Direct Offering of $ 7.5 million with net proceeds of approximately $ 6.7 million after deducting $ 0.8 million in commissions and other transaction costs. In connection with the May 2023 Registered Direct Offering, the Company paid H.C. Wainwright & Co., LLC, as exclusive placement agent, an aggregate cash fee equal to 7.0 % of the gross proceeds received by the Company from the offering and a management fee equal to 1.0 % of the gross proceeds received by the Company from the offering. The Company also paid the placement agent $ 75,000 for non-accountable expenses and $ 15,950 for clearing fees. Additionally, the Company issued designees of the placement agent the May 2023 Placement Agent Warrants, equal to 7.0 % of the aggregate number of shares of common stock and pre-funded warrants placed in the offering. The June 2023 Registered Direct Offering included the issuance and sale of an aggregate of 5,950,000 shares of the Company’s common stock at a purchase price of $ 1.125 per share in a registered direct offering priced at-the-market under Nasdaq rules. In addition, the offering included the issuance of the June 2023 Pre-Funded Warrants, which were immediately exercised, and the June 2023 Common Stock Warrants. The Company received gross proceeds from the June 2023 Registered Direct Offering of $ 8.7 million with net proceeds of approximately $ 7.8 million after deducting $ 0.9 million in commissions and other transaction costs. In connection with the June 2023 Registered Direct Offering, the Company paid H.C. Wainwright & Co., LLC, as exclusive placement agent, an aggregate cash fee equal to 7.0 % of the gross proceeds received by the Company from the offering and a management fee equal to 1.0 % of the gross proceeds received by the Company from the offering. The Company also paid the placement agent $ 50,000 for non-accountable expenses and $ 15,950 for clearing fees. Additionally, the Company issued designees of the placement agent the June 2023 Placement Agent Warrants, equal to 7.0 % of the aggregate number of shares of common stock and pre-funded warrants placed in the offering. Preferred Stock Upon closing of the Business Combination transaction, pursuant to the terms of the Amended and Restated Certificate of Incorporation, 100,000,000 shares of preferred stock with a par value of $ 0.0001 per share were authorized. eFFECTOR's Board of Directors (the "Board of Directors") has the authority, without further action by the stockholders to issue such shares of preferred stock in one or more series, to establish from time to time the number of shares to be included in each such series, and to fix the dividend, voting, and other rights, preferences and privileges of the shares. There were no issued and outstanding shares of preferred stock immediately after the closing of the Business Combination and no preferred stock has been issued as of June 30, 2023. Employee Stock Purchase Plan The ESPP provides for six-month offering periods, and at the end of each offering period, employees are able to purchase shares at 85 % of the lower of the fair market value of the Company’s common stock on the first trading day of the offering period or on the last trading day of the offering period. An aggregate of 880,000 shares were initially reserved and available for issuance under the ESPP. The ESPP provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1, beginning on January 1, 2022, by 1.0 % of the outstanding number of shares of common stock on the immediately preceding December 31, or such lesser amount as determined by our Board of Directors; provided that the total number of shares of common stock that become available for issuance under the ESPP will never exceed 15,000,000 . If our capital structure changes because of a stock dividend, stock split or similar event, the number of shares that can be issued under the ESPP will be appropriately adjusted. As of June 30, 2023 , 1,524,183 shares were reserved for future issuance under the ESPP. During the three and six months ended June 30, 2023, 93,562 shares of common stock were issued under the ESPP. During the three and six months ended June 30, 2022, 27,428 shares of common stock were issued under the ESPP. 2013 Equity Incentive Plan Prior to the Business Combination, Old eFFECTOR maintained its 2013 Equity Incentive Plan (the “2013 Plan”), under which Old eFFECTOR granted incentive stock options, restricted stock awards, and other stock-based awards to employees, directors, and non-employee consultants. Upon completion of the Business Combination, the Company ceased granting awards under the 2013 Plan and, as described below, all awards under the 2013 Plan were converted into awards under the 2021 Plan with the same terms and conditions. As of August 25, 2021, prior to the Business Combination transaction, 3,920,657 Old eFFECTOR options remained outstanding under the 2013 Plan. As of June 30, 2023 , the number of shares reserved and options outstanding under the 2013 Plan was 3,314,227 . There were zero shares available for grant under the 2013 Plan as of June 30, 2023. In connection with the completion of the Business Combination and the adoption of the 2021 Plan, no further awards will be granted under the 2013 Plan. 2021 Equity Incentive Plan In connection with the consummation of the Business Combination on August 25, 2021, the Board of Directors approved the adoption of the 2021 Equity Incentive Plan (the “2021 Plan”). As of June 30, 2023, 11,153,615 shares of common stock are authorized for issuance pursuant to awards under the 2021 Plan, inclusive of any shares of common stock subject to stock options, restricted stock awards or other awards that were assumed in the Business Combination. As of June 30, 2023, 8,948,410 options to purchase common shares have been awarded and 2,789,580 shares remain available for issuance under the 2021 Plan. The 2021 Plan permits the granting of incentive stock options, restricted stock awards, other stock-based award or other cash-based awards to employees, directors, and non-employee consultants. Options granted under the 2021 Plan are exercisable at various dates as determined upon grant and will expire no more than ten years from their date of grant, or in the case of certain non-statutory options, ten years from the date of grant. The exercise price of each option shall be determined by the Board of Directors based on the fair market value of the Company’s stock on the date of the option grant, defined as the closing sales price of the Company's common stock. In the case of incentive stock options, the exercise price shall not be less than 100 % of the fair market value of the Company’s common stock at the time the option is granted. For holders of more than 10 % of the Company’s total combined voting power of all classes of stock, incentive stock options may not be granted at less than 110 % of the fair market value of the Company’s stock at the date of grant and for a term not to exceed five years. A summary of the Company’s stock option activity under the plans is as follows (in thousands, except share and per share amounts and years): Shares Weighted- Weighted- Aggregate Outstanding at December 31, 2022 8,738,880 $ 2.73 7.4 $ — Granted 3,350,001 0.49 9.6 Exercised ( 56,008 ) 0.52 — Cancelled or forfeited ( 354,611 ) 2.10 7.0 Outstanding at June 30, 2023 11,678,262 $ 2.12 7.7 $ 1,375 Vested and exercisable at June 30, 2023 5,681,498 $ 2.40 6.1 $ 228 For the six months ended June 30, 2023 the total fair value of vested options was $ 2.7 million . The weighted-average grant date fair value of employee and non-employee option grants during the six months ended June 30, 2023 was $ 0.35 per share. Stock-Based Compensation Expense The Company recognized stock-based compensation expense specifically related to stock options of $ 1.2 million and $ 2.3 million for the three and six months e nded June 30, 2023, and $ 1.2 million and $ 2.1 million for the three and six months ended June 30, 2022, respectively. The assumptions used in the Black-Scholes option pricing model to determine the fair value of the stock option grants were as follows: Six Months Ended June 30, 2023 2022 Risk-free interest rate 3.6 % - 4.1 % 1.7 % - 3.3 % Expected volatility 84 % - 85 % 82 % - 86 % Expected term (in years) 5.3 - 6.1 5.2 - 6.1 Expected dividend yield 0 % 0 % Risk-free interest rate. The risk-free rate assumption is based on the U.S. Treasury instruments, the terms of which were consistent with the expected term of the Company’s stock options. Expected volatility. Due to the Company’s limited operating history and lack of company-specific historical or implied volatility, the expected volatility assumption was determined by examining the historical volatilities of a group of industry peers whose share prices are publicly available. Expected term. The expected term of stock options represents the weighted-average period the stock options are expected to be outstanding. The Company uses the simplified method for estimating the expected term as provided by the SEC. The simplified method calculates the expected term as the weighted average of the time-to-vesting and the contractual life of the options. Expected dividend yield. The expected dividend assumption is based on the Company’s history and expectation of dividend payouts. The Company has not paid and does not intend to pay dividends. Forfeitures . The Company reduces stock-based compensation expense for actual forfeitures during the period in which they occur. As of June 30, 2023 , the unrecognized compensation cost related to outstanding employee options was $ 6.5 million and is expected to be recognized as expense over approximately 2.5 years. Unrecognized compensation cost related to outstanding nonemployee options was $ 1.1 million as of June 30, 2023, and is expected to be recognized as expense over approximately 1.2 years. Common Stock Reserved for Future Issuance Common stock reserved for future issuance consists of the following as of June 30, 2023: June 30, Stock options issued and outstanding 11,678,262 Public warrants issued and outstanding 5,833,323 Private placement warrants issued and outstanding 181,667 Common stock warrants issued and outstanding 19,214,827 Placement agent warrants issued and outstanding 1,345,038 Earn-Out shares 5,000,000 Unvested sponsor shares 300,000 Authorized for future stock awards or option grants 2,789,580 Authorized for future issuances under the ESPP 1,524,183 Total 47,866,880

Earn-out Shares

Earn-out Shares	6 Months Ended
	Jun. 30, 2023
Earn out Share [Abstract]
Earn-out Shares	10. Earn-Out Shares In accordance with the Merger Agreement, 5,000,000 Earn-Out Shares are contingently issuable to Old eFFECTOR stockholders and option holders upon the occurrence of the Triggering Event, defined within the Merger Agreement as the date on which the common stock price equals or exceeds $ 20.00 over at least 20 trading days out of 30 consecutive trading day period for the two-year period following the close date of the Business Combination. As of June 30, 2023 and December 31, 2022, the stockholders and option holders would be eligible to receive approximately 4,561,353 and 438,647 Earn-Out Shares, respectively. The fair value per share of the Earn-Out Shares was less than $ 0.01 as of June 30, 2023 and December 31, 2022 . The fair value was determined using a Monte Carlo simulation valuation model using a distribution of potential outcomes on a monthly basis over the earn-out period using the most reliable information available. Assumptions used in the valuation were as follows: June 30, December 31, Stock price $ 0.83 $ 0.43 Expected volatility 115.0 % 115.0 % Risk-free interest rate 5.4 % 4.8 % Forecast period (in years) 0.2 0.6 Cost of equity 20.0 % 20.0 % Old eFFECTOR Shareholders The Company has determined that the contingent obligation to issue Earn-Out Shares to existing Old eFFECTOR shareholders is not indexed to the Company's stock under ASC 815-40 and therefore equity treatment is precluded. The Triggering Event that determines the issuance of the Earn-Out Shares includes terms that are not solely indexed to the common stock of the Company, and as such liability classification is required. As of the consummation date of the Business Combination, the estimated fair value of the shareholder Earn-Out Shares was approximately $ 61.0 million and the Company will revalue the liability each reporting period with the changes in fair value being recorded to the consolidated statements of operations and comprehensive loss. There was no increase or decrease in the earn-out liability during the three and six months ended June 30, 2023. For the three and six months ended June 30, 2022, there was a decrease in the earn-out liability of $ 1.3 million and $ 12.0 million, respectively, which was recorded as a gain on change in fair value within the statement of operations and comprehensive loss. In accordance with the Merger Agreement, Earn-Out Shares attributable to Old eFFECTOR option holders who discontinue providing service before the occurrence of the Triggering Event are reallocated to the remaining eligible stockholders and option holders. The following table presents activity for the earn-out liability measured at fair value using significant unobservable Level 3 inputs at December 31, 2022 and June 30, 2023 (in thousands): Earn-out Liability Balance at December 31, 2022 $ 6 Change in fair value — Balance at June 30, 2023 $ 6 Old eFFECTOR Option Holders The contingent obligation to issue Earn-Out Shares to existing Old eFFECTOR option holders falls within the scope of ASC 718, Share-based Compensation, because the option holders are required to continue providing service until the occurrence of the Triggering Event. The fair value of the option holder Earn-Out Shares at the consummation date of the Business Combination was approximately $ 7.9 million, which was recorded as share-based compensation over the derived service period of 0.36 years following the consummation of the Business Combination. There was zero share-based compensation recorded for the three and six months ended June 30, 2023 related to the Earn-Out Shares. For the three and six months ended June 30, 2022, there was approximately zero and $ 0.3 million, respectively, recorded in share-based compensation related to the Earn-Out Shares and the derived service period was completed as of March 31, 2022, with no additional share-based compensation expense to be recorded.

License Agreements

License Agreements	6 Months Ended
	Jun. 30, 2023
License Agreement Disclosure [Abstract]
License Agreement	11. License Agreements In May 2013, the Company entered into an agreement with the Regents of the University of California (“UCSF”) which provides the Company with an exclusive license to UCSF’s patent rights in certain inventions (the “UCSF Translational Profiling Patent Rights”) relating to translational profiling laboratory techniques initially developed at UCSF. Under the agreement, the Company is permitted to research, develop, make and sell products that it discovers and develops utilizing the UCSF Translational Profiling Patent Rights, which the Company refers to as licensed products, and use certain licensed processes utilizing the UCSF Translational Profiling Patent Rights and to sublicense such licensed products and processes. In July 2021, the Company entered into an amendment to the license agreement to confirm the impact of the Business Combination on the license agreement, including clarifying that in connection with the closing of the Business Combination, the Company would pay UCSF a one-time cash payment of approximately $ 1.0 million. The $ 1.0 million payment was made to UCSF in August 2021 in connection with the close of the Business Combination. The Company is also required to make cash milestone payments to UCSF upon the completion of certain clinical and regulatory milestones for the licensed products. No milestone events occurred during the three and six months ended June 30, 2023 and June 30, 2022. The aggregate remaining potential milestone payments are approximately $ 375,000 . The Company paid an annual minimum royalty of $ 15,000 to UCSF during each of the six months ended June 30, 2023 and 2022. All license related fees were recorded as research and development expense.

Research Collaboration and Lice

Research Collaboration and License Agreement	6 Months Ended
	Jun. 30, 2023
Research and Development [Abstract]
Research Collaboration and License Agreement	12. Research Collaboration and License Agreement In December 2019, the Company entered into a Research Collaboration and License Agreement (the “Pfizer Agreement”) with Pfizer to research and develop small molecules that target eIF4E. Under the Pfizer Agreement, the Company was responsible for initial research in collaboration with Pfizer, and Pfizer is responsible for all further development of the program, including submission of an investigational new drug application and conducting all clinical development and commercialization activities. Pfizer is obligated to use commercially reasonable efforts to develop and seek regulatory approval for a licensed product, and commercialize a licensed product where Pfizer has received regulatory approval, in the United States and certain other countries. In the event the Company exercises its co-funding and co-promotion option, a joint steering committee will oversee the development plan and budget of the co-developed product, and the Company will have the responsibility to conduct a portion of product marketing presentations to healthcare providers. Pursuant to the Pfizer Agreement, the Company received an upfront, one-time, non-refundable, non-creditable payment of $ 15 million from Pfizer. Pfizer was obligated to reimburse the Company for costs incurred for research performed, up to a specified cap in the low double-digit millions. Upon the achievement of specified early development and regulatory milestones, Pfizer will be obligated to pay the Company up to $ 80 million in the aggregate. For other non-early stage development milestones Pfizer’s payment obligations to the Company depends upon whether the Company has exercised its co-funding and co-promotion option: 1) if it does not exercise the option, non-early stage development payments may total up to $ 165 million in aggregate, and 2) if it does exercise the option, non-early stage development payments may total up to $ 70 million in aggregate. Upon the achievement of specified sales milestones, Pfizer is also obligated to make tiered milestone payments of up to $ 235 million in aggregate. On a product-by-product basis, Pfizer will also be required to pay the Company high single-digit percentage royalties on annual net sales of each licensed product. If the Company exercises its co-promotion and co-funding option, royalty payments will exclude sales in the United States and the Company will share with Pfizer profits from sale of the relevant licensed product in the United States. The initial transaction price of $ 27.0 million was allocated to the two performance obligations on a relative standalone value basis, with $ 25.6 million allocated to the license and $ 1.4 million allocated to the research activities , which were completed in 2020. The value attributable to the license was recognized upon delivery of the license to Pfizer and the value attributable to the research activities was recognized pro-rata based on the actual costs incurred by the Company compared to the total estimated costs of the research activities from the time of execution to the end of the research program. There was no revenue recorded in connection with this agreement for the three and six months ended June 30, 2023 and 2022 because all development and sales milestones (variable consideration) were fully constrained.

DARPA Grant Revenue

DARPA Grant Revenue	6 Months Ended
	Jun. 30, 2023
DARPA Grant Revenue Disclosure [Abstract]
DARPA Grant Revenue	13. DARPA Grant Revenue In April 2021, the Company entered into a Research Subaward Agreement with UCSF (the "Subaward Agreement"), whereby up to $ 5.0 million in allowable costs were reimbursable for clinical and manufacturing activities related to zotatifin for the treatment of COVID-19. Under the terms of the Subaward Agreement, the Company was obligated to provide financial and technical reports to UCSF on a periodic basis. The Subaward Agreement can be terminated by either party upon written notice and also in the event that DARPA suspends or terminates its cooperative agreement with UCSF. The initial award period for the Subaward Agreement ended in December 2021, and in April 2022 the Company received an extension of the award period to December 2022, with the same maximum $ 5.0 million reimbursement amount. The Company did no t recognize any revenue under the Subaward Agreement in the three and six months ended June 30, 2023. The Company recognized $ 2.0 million of revenue under the Subaward Agreement in the three and six months ended June 30, 2022. As of December 31, 2022, the Company exhausted the full $ 5.0 million of allowable reimbursable costs under the Subaward Agreement.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	14. Commitments and Contingencies Leases In September 2021, the Company entered a non-cancelable three-year lease for certain office space in Solana Beach, California, with an option to renew for an additional three-year term. The initial term of the lease started on November 1, 2021, and is serving as the Company's headquarters. Rent expense under this lease was $ 16,000 and $ 33,000 for the three and six months ended June 30, 2023 and 2022, respectively. During the three and six months ended June 30, 2023, the Company paid $ 17,000 and $ 30,000 , respectively, in lease payments. During the three and six months ended June 30, 2022, the Company paid $ 18,000 and $ 35,000 , respectively, in lease payments. All lease payments were included in operating activities in the statements of cash flows. The following table summarizes supplemental balance sheet information related to leases as of June 30, 2023 and December 31, 2022. June 30, December 31, Assets: Operating lease right-of-use assets $ 83 $ 111 Total right-of-use assets 83 111 Liabilities Operating lease liabilities, current 69 60 Operating lease liabilities, non-current 25 60 Total operating lease liabilities $ 94 $ 120 As of June 30, 2023, the future minimum annual lease payments under the existing operating leases were as follows (in thousands, except for weighted-average remaining lease term and weighted-average discount rate): Remainder of 2023 $ 37 2024 62 Total remaining lease payments 99 Less: imputed interest ( 5 ) Total operating lease liabilities 94 Less: current portion ( 69 ) Long-term operating lease liabilities $ 25 Weighted-average remaining lease term ( in years ) 1.33 Weighted-average discount rate 8 %

Employee Benefits

Employee Benefits	6 Months Ended
	Jun. 30, 2023
Retirement Benefits [Abstract]
Employee Benefits	15. Employee Benefits The Company has a defined contribution 401(k) plan available to eligible employees. Under the terms of the plan, employees may make voluntary contributions as a percent of compensation, limited to the maximum amount allowable under federal tax regulations. The Company, at its discretion, may make certain contributions to the 401(k) plan. Through June 30, 2023 , the Company made no matching contributions.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements as of June 30, 2023 and for the three and six months ended June 30, 2023 and 2022 have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and pursuant to Article 10 of Regulation S-X of the Securities Act of 1933, as amended (the “Securities Act”). Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. These unaudited financial statements include only normal and recurring adjustments that the Company believes are necessary to fairly state the Company’s financial position and the results of its operations and cash flows. The results for the three and six months ended June 30, 2023 are not necessarily indicative of the results expected for the full fiscal year or any subsequent interim period. The balance sheet at December 31, 2022 has been derived from the audited financial statements at that date but does not include all the disclosures required by GAAP for complete financial statements. Because all of the disclosures required by GAAP for complete financial statements are not included herein, these unaudited financial statements and the notes accompanying them should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2022 included in its Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 8, 2023.
Liquidity	Liquidity The Company has a limited operating history and the sales and income potential of the Company’s business and market are unproven. The accompanying financial statements have been prepared assuming the Company will continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or amounts and classification of liabilities that may result from the outcome of this uncertainty. Management is required to perform a two-step analysis over its ability to continue as a going concern. Management must first evaluate whether there are conditions and events that raise substantial doubt about the Company’s ability to continue as a going concern (step 1). If management concludes that substantial doubt is raised, management is also required to consider whether its plans alleviate that doubt (step 2). The Company has experienced net losses and negative cash flows from operating activities since its inception, aside from the years ended December 31, 2021 and December 31, 2020 when net income was realized as a result of a gain in fair value recognized associated with the earn-out liability and revenue in connection with the Research Collaboration and License Agreement with Pfizer, respectively. The Company has an accumulated deficit of $ 161.9 million at June 30, 2023. For the six months ended June 30, 2023, the Company used $ 16.2 million in cash for operations. At June 30, 2023, the Company had cash and cash equivalents and short-term investments of $ 25.0 million. The Company anticipates that its expenses will increase significantly in connection with its ongoing activities to support its research and development efforts, and it expects to incur substantial operating losses and negative cash flows from operations for the foreseeable future. Management has prepared cash flow forecasts which indicate that based on the Company’s expected operating losses and negative cash flows, there is substantial doubt about the Company’s ability to continue as a going concern within twelve months from the date that these financial statements for the three and six months ended June 30, 2023 are issued. The principal payments due under the Oxford Loans (as defined below), and the related accrued final payment, have been classified as current liabilities as of June 30, 2023, due to the considerations discussed above and the assessment that the material adverse change clause under the Oxford Loans is not within the Company’s control. The Company has not been notified of an event of default by the lender as of the date of issuance of these financial statements. The Company’s ability to continue as a going concern is dependent upon its ability to receive additional capital. Management intends to raise additional capital through equity offerings or other capital sources, including potential additional collaborations, licenses and other similar arrangements. Additionally, the Company may receive additional milestone payments from the Research Collaboration and License Agreement with Pfizer (described in Note 12), through the issuance of common stock under the equity purchase agreement (the "Purchase Agreement") with Lincoln Park Capital Fund, LLC ("Lincoln Park") (described in Note 9) or through the issuance of common stock under the at-the-market offering program (described in Note 9) with Cantor Fitzgerald & Co ("Cantor"). However, the Company may not be able to secure additional financing in a timely manner or on favorable terms, if at all, and may not receive any milestone payments. Without additional capital, the Company may be forced to delay, scale back or eliminate some of its research and development activities, or other operations and potentially delay product development in an effort to provide sufficient funds to continue its operations, or may be required to pursue merger or acquisition strategies, all of which could adversely affect the holdings or the rights of its stockholders.
Research and Development Costs	Research and Development Costs Research and development expenses primarily consist of costs associated with the preclinical and clinical development of the Company’s product candidates. Research and development costs are expensed as incurred.
Clinical Trial Accruals and Preclinical Studies	Clinical Trial Accruals and Preclinical Studies The Company records expenses resulting from our obligations under contracts with vendors and consultants, CROs and clinical sites in connection with conducting clinical trials and preclinical studies. The financial terms of these contracts are subject to negotiations which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company reflects clinical trial and preclinical study expenses in the financial statements by matching those expenses with the period in which services and efforts are expended. The Company accounts for these expenses according to the progress of the clinical trial or preclinical study as measured by the timing of various aspects of the clinical trial, preclinical study, or related activities. The Company determines accrual estimates based on the underlying contracts, correspondence with clinical and other key personnel and third-party service providers as to the progress of the clinical trials, preclinical studies, or other services being conducted, and amounts invoiced or paid to date. During the course of a clinical trial or preclinical study, the Company adjusts the rate of expense recognition if actual results differ from estimates.
Public and Private Placement Warrants	Public and Private Placement Warrants Upon completion of the Business Combination, the Company assumed public and private placement warrants that were issued by LWAC in connection with their initial public offering in January 2021 whereby holders of the public and private placement warrants are entitled to acquire common stock of the Company. The Company has concluded that the public warrants are equity-classified. Because the settlement value of the private placement warrants is dependent, in part, on who holds the warrants at the time of settlement, they are not considered indexed to the Company's stock and are therefore recorded as liabilities. Warrants classified as liabilities are recorded at their estimated fair value on the date of issuance and are revalued at each subsequent balance sheet date, with fair value changes recognized in other income (expense), net in the accompanying consolidated statements of operations and comprehensive loss. The Company estimates the fair value of these warrants using the Black-Scholes option pricing model.
Stock-Based Compensation Expense	Stock-Based Compensation Expense Stock-based compensation expense represents the cost of the grant date fair value of employee stock option grants recognized over the requisite service period of the awards (usually the vesting period) on a straight- line basis. The Company estimates the fair value of stock option grants using the Black-Scholes option-pricing model. The Company accounts for stock options granted to non-employees using the fair value approach. The Black-Scholes option-pricing model requires the use of subjective assumptions, including the risk-free interest rate, the expected stock price volatility, the expected term of stock options, and the expected dividend yield. The Company has limited historical stock option activity and therefore estimates the expected term of stock options granted using the simplified method, which represents the average of the contractual term of the stock option and its weighted-average vesting period. The fair value of the underlying common stock used within the Black-Scholes option-pricing model is based on the closing price of common stock on the date of grant.
Earn-Out Shares	Earn-Out Shares In accordance with the Merger Agreement, 5,000,000 shares ("Earn-Out Shares") are contingently issuable to Old eFFECTOR stockholders and option holders upon the occurrence of the Triggering Event, defined within the Merger Agreement as the date on which the common stock price equals or exceeds $ 20.00 over at least 20 trading days out of a 30 consecutive trading day period during the two-year period following the close date of the Business Combination. The estimated fair value of the Earn-Out Shares was determined using a Monte Carlo simulation valuation model using a distribution of potential outcomes on a monthly basis over the earn-out period using the most reliable information available. The Company has determined that the contingent obligation to issue Earn-Out Shares to existing Old eFFECTOR shareholders is not indexed to the Company's stock under Accounting Standards Codification ("ASC") 815-40 and therefore equity treatment is precluded. The Triggering Event that determines the issuance of the Earn-Out Shares includes terms that are not solely indexed to our common stock, and as such liability classification is required. Equity-linked instruments classified as liabilities are recorded at their estimated fair value on the date of issuance and are revalued at each subsequent balance sheet date, with fair value changes recognized in other income (expense), net in the accompanying consolidated statements of operations and comprehensive loss. The Company has determined that the contingent obligation to issue Earn-Out Shares to existing Old eFFECTOR option holders falls within the scope of ASC 718, Share-based Compensation, because the option holders are required to continue providing service until the occurrence of the Triggering Event. The fair value of the option holder Earn-Out Shares is recorded as share-based compensation over the derived service period of the Monte Carlo simulation valuation model, recognized in research and development and general and administrative expense in the consolidated statements of operations and comprehensive loss.
Comprehensive Loss	Comprehensive Loss Comprehensive loss consists of net loss and unrealized gains or losses on available-for-sale investments. The Company presents comprehensive loss and its components as part of the consolidated statements of operations and comprehensive loss.
Cash, Cash Equivalents and Short-term Investments	Cash, Cash Equivalents and Short-term Investments Cash and Cash Equivalents The Company considers all highly liquid investments with insignificant interest rate risk and an original maturity of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents consist of money market funds and U.S. Treasury securities with an original maturity of three months or less at the date of purchase. Short-term Investments Short-term investments consist of U.S. Treasury securities, classified as available-for-sale securities and have maturities of greater than three months but less than one year. The Company has classified all of its available-for-sale securities as current assets on the balance sheets because these are considered highly liquid securities and are available for use in current operations. The Company carries these securities at fair value and reports unrealized gains and losses as a separate component of accumulated other comprehensive income (loss). Amortization and accretion of any purchase premiums or discounts is included in interest income in the consolidated statements of operations and comprehensive loss.
Recent Accounting Guidance	Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board ("FASB") or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes, based on its preliminary assessment, that the impact of recently issued standards that are not yet effective will not have a material impact on their financial position or results of operations upon adoption.
Net Income (Loss) Per Share	Net Income (Loss) Per Share The Company computes net income (loss) per share in accordance with the FASB guidance for Earnings Per Share, which established standards regarding the computation of earnings per share by companies that have issued securities other than common stock that contractually entitle the holder to participate in earnings and dividends. The guidance requires earnings available to common shareholders for the period, after deduction of preferred stock preferences, to be allocated between the common and preferred shareholders based on their respective rights to receive dividends. Basic net income (loss) per share is calculated by dividing income (loss) allocable to common shareholders by the weighted-average number of common shares outstanding, during the period. The Company calculates diluted net income per share using the more dilutive of the 1) treasury stock method, if-converted method, or contingently issuable share method, as applicable, or 2) the two-class method. Due to the Company recording net loss for the three and six months ended June 30, 2023 and 2022 and none of the outstanding securities being dilutive for those periods, basic and diluted loss per share are the same for each respective period presented. Potentially dilutive s ecurities as of June 30, 2023 and 2022 are as follows (in common stock equivalent shares): As of June 30, 2023 2022 Common stock warrants 19,214,827 — Placement agent warrants 1,345,038 — Public warrants 5,833,323 5,833,323 Private placement warrants 181,667 181,667 Earn-Out Shares 5,000,000 5,000,000 Unvested sponsor shares 300,000 300,000 Stock options outstanding 11,678,262 8,102,034 Total 43,553,117 19,417,024

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Schedule of Computation of Basic and Diluted Net Income (Loss) Per Share
Schedule of Potentially Dilutive Securities	Potentially dilutive s ecurities as of June 30, 2023 and 2022 are as follows (in common stock equivalent shares): As of June 30, 2023 2022 Common stock warrants 19,214,827 — Placement agent warrants 1,345,038 — Public warrants 5,833,323 5,833,323 Private placement warrants 181,667 181,667 Earn-Out Shares 5,000,000 5,000,000 Unvested sponsor shares 300,000 300,000 Stock options outstanding 11,678,262 8,102,034 Total 43,553,117 19,417,024

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2023
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Summary of assets and liabilities measured at fair value on a recurring basis	The following table summarizes the Company’s assets and liabilities that require fair value measurements on a recurring basis and their respective input levels based on the fair value hierarchy as of June 30, 2023 and December 31, 2022 (in thousands): Fair Value Measurements Using June 30, Quoted Prices Significant Significant 2023 Level 1 Level 2 Level 3 Assets Cash equivalents: Money market funds $ 12,731 $ 12,731 $ — $ — U.S. Treasury securities 1,983 — 1,983 — Short-term investments: U.S. Treasury securities 10,305 — 10,305 — Total assets $ 25,019 $ 12,731 $ 12,288 $ — Liabilities Private placement warrant liability $ 40 $ — $ — $ 40 Earn-out liability 6 — — 6 Total liabilities $ 46 $ — $ — $ 46 Fair Value Measurements Using December 31, Quoted Prices Significant Significant 2022 Level 1 Level 2 Level 3 Assets Cash equivalents: Money market funds $ 8,708 $ 8,708 $ — $ — Short-term investments: U.S. Treasury securities 17,602 — 17,602 — Total assets $ 26,310 $ 8,708 $ 17,602 $ — Liabilities Private placement warrant liability $ 40 $ — $ — $ 40 Earn-out liability 6 — — 6 Total liabilities $ 46 $ — $ — $ 46
Summary of Short term Investment	The following tables summarize the Company’s short-term investments accounted for as available-for-sale securities as of June 30, 2023 and December 31, 2022 (in thousands): June 30, 2023 Maturity Amortized Unrealized Unrealized Estimated (in years) Cost Gains Losses Fair Value U.S. Treasury securities 1 year or less $ 12,287 $ 2 $ ( 1 ) $ 12,288 $ 12,287 $ 2 $ ( 1 ) $ 12,288 December 31, 2022 Maturity Amortized Unrealized Unrealized Estimated (in years) Cost Gains Losses Fair Value U.S. Treasury securities 1 year or less $ 17,620 $ 1 $ ( 19 ) $ 17,602 $ 17,620 $ 1 $ ( 19 ) $ 17,602
Private Placement Warrants Liability [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Summary of fair value measurements inputs	The following key assumptions were used in determining the fair value of the private placement warrant liability valued using the Black-Scholes option pricing model as of June 30, 2023 and December 31, 2022: June 30, December 31, Common stock price $ 0.83 $ 0.43 Expected volatility 125.0 % 125.0 % Risk-free interest rate 4.5 % 4.2 % Expected term (in years) 3.2 3.7 Expected dividend yield — —
Summary of change in fair value of derivative warrant liabilities	The following table presents activity for the private placement warrant liability measured at fair value using significant unobservable Level 3 inputs during the six months ended June 30, 2023 (in thousands): Private Placement Warrant Liability Balance at December 31, 2022 $ 40 Change in fair value — Balance at June 30, 2023 $ 40

Property and Equipment , net (T

Property and Equipment , net (Tables)	6 Months Ended
	Jun. 30, 2023
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment ,net	Property and equipment, net consists of the following (in thousands): June 30, December 31, Lab equipment $ 30 $ 30 Computer and office equipment 154 149 Furniture and fixtures 78 61 Leasehold improvements 188 188 Construction in process 37 29 487 457 Less accumulated depreciation and amortization ( 271 ) ( 216 ) $ 216 $ 241

Accrued Expenses (Tables)

Accrued Expenses (Tables)	6 Months Ended
	Jun. 30, 2023
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consist of the following (in thousands): June 30, December 31, Employee compensation $ 946 $ 1,385 Research and development 465 1,206 Professional and outside services 298 112 Interest 212 197 Other 2 468 $ 1,923 $ 3,368

Term Loans (Tables)

Term Loans (Tables)	6 Months Ended
	Jun. 30, 2023
Notes and Loans Payable, by Type, Current and Noncurrent [Abstract]
Schedule of Principal Future Payments of Term Loans	Based on the outstanding principal amounts for the Company’s Term A Loans, the following table sets forth by year the Company’s required future principal payments as of June 30, 2023 (in thousands): As of June 30, 2023 2024 $ 5,555 2025 6,667 2026 6,667 2027 1,111 Required future principal payments $ 20,000 Unamortized debt discount ( 784 ) Current term loans, net as of June 30, 2023 $ 19,216

Warrants (Tables)

Warrants (Tables)	6 Months Ended
	Jun. 30, 2023
Class of Warrant or Right [Table]
Summary of Public and private placement warrants outstanding.	The following table summarizes the number of outstanding public warrants and private placement warrants and the corresponding exercise price as of June 30, 2023 and December 31, 2022: June 30, December 31, Exercise Price Expiration Date Public warrants 5,833,323 5,833,323 $ 11.50 August 24, 2026 Private placement warrants 181,667 181,667 $ 11.50 August 24, 2026
Warrant [Member]
Class of Warrant or Right [Table]
Summary of Public and private placement warrants outstanding.	The following table summarizes the number of outstanding common stock warrants and placement agent warrants and the corresponding exercise price as of June 30, 2023 and December 31, 2022: June 30, December 31, Exercise Price Expiration Date May 2023 Common Stock Warrants 11,450,382 — $ 0.53 November 30, 2028 May 2023 Placement Agent Warrants 801,527 — $ 0.8188 May 26, 2028 June 2023 Common Stock Warrants 7,764,445 — $ 1.00 December 8, 2028 June 2023 Placement Agent Warrants 543,511 — $ 1.4063 June 6, 2028

Preferred Stock and Stockhold_2

Preferred Stock and Stockholders' Deficit (Tables)	6 Months Ended
	Jun. 30, 2023
Equity [Abstract]
Summary of option activity under the company's plans	A summary of the Company’s stock option activity under the plans is as follows (in thousands, except share and per share amounts and years): Shares Weighted- Weighted- Aggregate Outstanding at December 31, 2022 8,738,880 $ 2.73 7.4 $ — Granted 3,350,001 0.49 9.6 Exercised ( 56,008 ) 0.52 — Cancelled or forfeited ( 354,611 ) 2.10 7.0 Outstanding at June 30, 2023 11,678,262 $ 2.12 7.7 $ 1,375 Vested and exercisable at June 30, 2023 5,681,498 $ 2.40 6.1 $ 228
Schedule of assumptions used in the Black-Scholes option pricing model to determine the fair value of the stock option grants.	Six Months Ended June 30, 2023 2022 Risk-free interest rate 3.6 % - 4.1 % 1.7 % - 3.3 % Expected volatility 84 % - 85 % 82 % - 86 % Expected term (in years) 5.3 - 6.1 5.2 - 6.1 Expected dividend yield 0 % 0 %
Schedule of Common Stock, Reserved for Future Issuance	Common stock reserved for future issuance consists of the following as of June 30, 2023: June 30, Stock options issued and outstanding 11,678,262 Public warrants issued and outstanding 5,833,323 Private placement warrants issued and outstanding 181,667 Common stock warrants issued and outstanding 19,214,827 Placement agent warrants issued and outstanding 1,345,038 Earn-Out shares 5,000,000 Unvested sponsor shares 300,000 Authorized for future stock awards or option grants 2,789,580 Authorized for future issuances under the ESPP 1,524,183 Total 47,866,880

Earn-out Shares (Tables)

Earn-out Shares (Tables)	6 Months Ended
	Jun. 30, 2023
Earn out Share [Abstract]
Schedule of Estimated Fair Value of the Earn Out Shares	Assumptions used in the valuation were as follows: June 30, December 31, Stock price $ 0.83 $ 0.43 Expected volatility 115.0 % 115.0 % Risk-free interest rate 5.4 % 4.8 % Forecast period (in years) 0.2 0.6 Cost of equity 20.0 % 20.0 %
Schedule of Activity for Earn Out Liability	The following table presents activity for the earn-out liability measured at fair value using significant unobservable Level 3 inputs at December 31, 2022 and June 30, 2023 (in thousands): Earn-out Liability Balance at December 31, 2022 $ 6 Change in fair value — Balance at June 30, 2023 $ 6

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of Supplemental Balance sheet Information related to Leases	The following table summarizes supplemental balance sheet information related to leases as of June 30, 2023 and December 31, 2022. June 30, December 31, Assets: Operating lease right-of-use assets $ 83 $ 111 Total right-of-use assets 83 111 Liabilities Operating lease liabilities, current 69 60 Operating lease liabilities, non-current 25 60 Total operating lease liabilities $ 94 $ 120
Schedule of Future Minimum Rental Payments for Operating Leases	As of June 30, 2023, the future minimum annual lease payments under the existing operating leases were as follows (in thousands, except for weighted-average remaining lease term and weighted-average discount rate): Remainder of 2023 $ 37 2024 62 Total remaining lease payments 99 Less: imputed interest ( 5 ) Total operating lease liabilities 94 Less: current portion ( 69 ) Long-term operating lease liabilities $ 25 Weighted-average remaining lease term ( in years ) 1.33 Weighted-average discount rate 8 %

Organization and Basis of Pre_2

Organization and Basis of Presentation - Additional Information (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Subsidiary Sale Of Stock [Line Items]
Place of incorporation	DE
Accumulated deficit	$ 161,944	$ 143,566
Cash from operation	16,200
Cash & Cash Equivalents in Securities	$ 25,000
Date of incorporation	Oct. 02, 2020
Locust Walk Acquisition Corp [Member]
Subsidiary Sale Of Stock [Line Items]
Conversion of outstanding common and preferred shares into common shares	0.09657

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail) - $ / shares	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock, shares issued	61,765,616	41,990,383
Common stock price per share	$ 0.0001	$ 0.0001
Consecutive trading days required for entitlement of common stock	30 days
Earn-Out Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock, shares issued	5,000,000
Common stock price per share	$ 20
Trading days required for entitlement of common stock	20 days
Consecutive trading days required for entitlement of common stock	30 days

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of basic and diluted net income (loss) per share (Detail) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Basic Net Income (Loss) per share
Weighted-average common shares outstanding, basic	47,828,631	41,118,727	44,930,987	40,984,273
Net loss per share, basic	$ (0.17)	$ (0.17)	$ (0.41)	$ (0.09)
Diluted Net income (Loss) per share
Weighted-average common shares outstanding, basic	47,828,631	41,118,727	44,930,987	40,984,273
Weighted-average common shares outstanding, diluted	47,828,631	41,118,727	44,930,987	40,984,273
Net loss per share, diluted	$ (0.17)	$ (0.17)	$ (0.41)	$ (0.09)

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Potentially Dilutive Securities (Detail) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Dilutive Securities (in common stock equivalent shares)	43,553,117	19,417,024
Public warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Dilutive Securities (in common stock equivalent shares)	5,833,323	5,833,323
Private Placement [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Dilutive Securities (in common stock equivalent shares)	181,667	181,667
Earn-Out Shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Dilutive Securities (in common stock equivalent shares)	5,000,000	5,000,000
Unvested sponsor shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Dilutive Securities (in common stock equivalent shares)	300,000	300,000
Stock Options Outstanding [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Dilutive Securities (in common stock equivalent shares)	11,678,262	8,102,034
Common stock warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Dilutive Securities (in common stock equivalent shares)	19,214,827	0
Placement agent warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Dilutive Securities (in common stock equivalent shares)	1,345,038	0

Business Combination - Addition

Business Combination - Additional Information (Detail) - $ / shares		6 Months Ended
	Aug. 25, 2021	Jun. 30, 2023
Business Acquisition [Line Items]
Trading days required for entitlement of common stock		20 days
Consecutive trading days required for entitlement of common stock		30 days
Old eFFECTOR Stockholders | Common Stock [Member]
Business Acquisition [Line Items]
Common stock up on conversion	4,056,250
LWAC Stockholders | Common Stock Subject to Vesting
Business Acquisition [Line Items]
Trading days required for entitlement of common stock	20 days
Consecutive trading days required for entitlement of common stock	30 days
Common stock up on conversion	300,000
LWAC Stockholders | Common Stock Subject to Vesting | Minimum
Business Acquisition [Line Items]
Trigger price of common stock for vesting of unvested shares	$ 15

Fair Value Measurementsn - Addi

Fair Value Measurementsn - Additional Information (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash & Cash Equivalents in Securities	$ 25,000,000
Short-term investments	10,305,000	$ 17,602,000
Fair Value, Inputs, Level 1, 2 and 3 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value, net derivative asset (liability) measured on recurring basis, unobservable inputs reconciliation, transfers, net	0	0
Investments in money market fund	12,700,000	8,700,000
Marketable Securities	12,300,000	17,600,000
Fair Value, Inputs, Level 1, 2 and 3 [Member] | Short-Term Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest Receivable	72,000	$ 27,000
Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash & Cash Equivalents in Securities	2,000,000
Short-term investments	$ 10,300,000

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Assets And Liabilities Measured At Fair Value On Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Liabilities
Earn-out liability	$ 6	$ 6
Fair Value, Recurring
Assets
Total assets	25,019	26,310
Liabilities
Earn-out liability	6	6
Total liabilities	46	46
Fair Value, Recurring | US Treasury Securities [Member]
Assets
U.S. Treasury securities	1,983
Fair Value, Recurring | Private Placement Warrant Liability
Liabilities
Warrant liability	40	40
Fair Value, Recurring | Fair Value Inputs Level 1
Assets
Total assets	12,731	8,708
Liabilities
Total liabilities	0	0
Fair Value, Recurring | Fair Value Inputs Level 2
Assets
Total assets	12,288	17,602
Liabilities
Total liabilities	0	0
Fair Value, Recurring | Fair Value Inputs Level 2 | US Treasury Securities [Member]
Assets
U.S. Treasury securities	1,983
Fair Value, Recurring | Fair Value Inputs Level 3
Assets
Total assets	0	0
Liabilities
Earn-out liability	6	6
Total liabilities	46	46
Fair Value, Recurring | Fair Value Inputs Level 3 | Private Placement Warrant Liability
Liabilities
Warrant liability	40	40
Fair Value, Recurring | Money Market Funds
Assets
Money market funds	12,731	8,708
Fair Value, Recurring | Money Market Funds | Fair Value Inputs Level 1
Assets
Money market funds	12,731	8,708
Fair Value, Recurring | Short-Term Investments [Member]
Assets
U.S. Treasury securities	10,305	17,602
Fair Value, Recurring | Short-Term Investments [Member] | Fair Value Inputs Level 2
Assets
U.S. Treasury securities	$ 10,305	$ 17,602

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Short term Investment (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 12,287	$ 17,620
Unrealized Gains	2	1
Unrealized Losses	(1)	(19)
Estimated Fair Value	$ 12,288	$ 17,602
U.S. Treasury Securities
Debt Securities, Available-for-Sale [Line Items]
Maturity (in years)	1 year	1 year
Amortized Cost	$ 12,287	$ 17,620
Unrealized Gains	2	1
Unrealized Losses	(1)	(19)
Estimated Fair Value	$ 12,288	$ 17,602

Fair Value Measurements - Sum_3

Fair Value Measurements - Summary of change in fair value of preferred stock warrant liability (Detail) - Series C Preferred Stock Warrant Liability [Member] $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value, Beginning Balance	$ 40
Change in fair value	0
Fair value, Ending Balance	$ 40

Fair Value Measurements - Sum_4

Fair Value Measurements - Summary of fair value measurements inputs of private placement warrant liability (Detail) - Private Placement Warrant Liability	Jun. 30, 2023 USD ($) yr	Dec. 31, 2022 yr USD ($)
Common Stock Price
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurement Input | $	0.83	0.43
Expected volatility
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurement Input	125	125
Risk-free interest rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurement Input	4.5	4.2
Expected term (in years)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurement Input | yr	3.2	3.7
Expected dividend yield
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurement Input	0	0

Property and Equipment, net - S

Property and Equipment, net - Summary of Property and Equipment, net (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	$ 487	$ 457
Less accumulated depreciation and amortization	(271)	(216)
Property and Equipment, Net	216	241
Lab Equipment
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	30	30
Computer and Office Equipment
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	154	149
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	78	61
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	188	188
Construction In Progress
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	$ 37	$ 29

Property and Equipment, net - A

Property and Equipment, net - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Property, Plant and Equipment [Abstract]
Depreciation and amortization	$ 27,000	$ 3,000	$ 55,000	$ 8,000

Accrued Expenses - Summary of A

Accrued Expenses - Summary of Accrued Expenses (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Employee compensation	$ 946	$ 1,385
Research and development	465	1,206
Professional and outside services	298	112
Interest	212	197
Other	2	468
Accrued liabilities, current	$ 1,923	$ 3,368

Term Loans - Additional Informa

Term Loans - Additional Information (Detail) $ / shares in Units, $ in Thousands		3 Months Ended			6 Months Ended
	Feb. 22, 2022 USD ($)	Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2022 USD ($)	Mar. 31, 2021 USD ($) Tranche	Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Outstanding principal, term loans		$ 19,216			$ 19,216
Extended cut off date before which the interest on term loan shall be paid	Mar. 01, 2024
Long term debt net of unamortized debt discounts		$ 20,000			$ 20,000
Loan and Security Agreement [Member] | Less Than One Year From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Prepayment fee as a percentage of the outstanding principal					3%
Loan and Security Agreement [Member] | Greater Than One Year And Less Than Two Years From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Prepayment fee as a percentage of the outstanding principal					2%
Loan and Security Agreement [Member] | Later Than Two Years And Not Later Than Three Years From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Prepayment fee as a percentage of the outstanding principal					1%
Loan and Security Agreement [Member] | Later Than Three Years From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Prepayment fee as a percentage of the outstanding principal					0%
Loan and Security Agreement [Member] | Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Number of tranches | Tranche				2
Debt instrument, face amount				$ 30,000
Number of days within which a portion of term loan will be available subject to achievement of milestone	45 days
Long term debt variable interest rate percentage		7.70%			7.70%
Loan and Security Agreement [Member] | Prime Rate [Member] | Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate spread					4.45%
Loan and Security Agreement [Member] | Warrants To Purchase Series C Redeemable Convertible Stock | Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Exercise price of warrants | $ / shares		$ 5.33			$ 5.33
Number of shares subject to each warrant | shares		37,575			37,575
Loan and Security Agreement [Member] | Common Stock [Member] | Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Common stock up on conversion | shares					17,575
Loan and Security Agreement [Member] | Debt Instrument, Term Loan A [Member] | Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Debt instrument, discount		$ 1,600			$ 1,600
Outstanding principal, term loans		20,000		20,000	20,000		$ 20,000
Amortization of debt discount		700	$ 500		$ 1,400	$ 1,000
Issuance of term loans, net of issuance costs				12,500
Extended maturity of term A loans, description	In connection with the amendment, the maturity of the Term A Loans was extended from March 18, 2026 to February 1, 2027.
Term loan final payment as a percentage of the amount funded					5.50%
Long term debt net of unamortized debt discounts		$ 19,200			$ 19,200		$ 19,200
Loan and Security Agreement [Member] | Debt Instrument, Term Loan B [Member]
Debt Instrument [Line Items]
Additional term loans	$ 10,000
Loan and Security Agreement [Member] | Debt Instrument, Term Loan B [Member] | Less Than One Year From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Loan initiation date	Jun. 30, 2023
Loan and Security Agreement [Member] | Debt Instrument, Term Loan B [Member] | Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Debt instrument, face amount				10,000
Issuance of term loans, net of issuance costs				$ 7,400

Term Loans - Schedule of Princi

Term Loans - Schedule of Principal Future Payments of Term Loans (Detail) $ in Thousands	Jun. 30, 2023 USD ($)
Notes and Loans Payable, by Type, Current and Noncurrent [Abstract]
2024	$ 5,555
2025	6,667
2026	6,667
2027	1,111
Required future principal payments	20,000
Unamortized debt discount	(784)
Current term loans, net as of June 30, 2023	$ 19,216

Warrants - Additional Informati

Warrants - Additional Information (Detail) - $ / shares	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Public Warrants and Private Placement Warrants [Member]
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 11.5
Exercise price of warrants	11.5
Class of warrants, redemption price per unit	$ 0.01
Class of warrants, redemption notice period	30 days
Share price	$ 18
Warrants and rights outstanding, term	5 years
Number of consecutive trading days for determining share price	20 days
Number of trading days to determine share price	30 days
May 2023 Common Stock Warrants
Class of Warrant or Right [Line Items]
Number of warrants	11,450,382	0
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.53
Expiration date	Nov. 30, 2028
Exercise price of warrants	$ 0.53
May 2023 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Number of warrants	801,527	0
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.8188
Expiration date	May 26, 2028
Exercise price of warrants	$ 0.8188
June 2023 Common Stock Warrants
Class of Warrant or Right [Line Items]
Number of warrants	7,764,445	0
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 1
Expiration date	Dec. 08, 2028
Exercise price of warrants	$ 1
June 2023 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Number of warrants	543,511	0
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 1.4063
Expiration date	Jun. 06, 2028
Exercise price of warrants	$ 1.4063
June 2023 Registered Direct Offering
Class of Warrant or Right [Line Items]
Number of warrants	1,814,445
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.001
Exercise price of warrants	0.001
Pre-funded warrants with a purchase price	$ 1.124
May 2023 Registered Direct Offering
Class of Warrant or Right [Line Items]
Number of warrants	6,750,382
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.001
Exercise price of warrants	0.001
Pre-funded warrants with a purchase price	$ 0.654

Warrants - Schedule of Public a

Warrants - Schedule of Public and private placement warrants outstanding (Detail) - $ / shares	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Public Warrants [Member]
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Outstanding	5,833,323	5,833,323
Exercise price of warrants	$ 11.5
Expiration date	Aug. 24, 2026
Private Placement Warrants [Member]
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Outstanding	181,667	181,667
Exercise price of warrants	$ 11.5
Expiration date	Aug. 24, 2026
May 2023 Common Stock Warrants
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Outstanding	11,450,382	0
Exercise price of warrants	$ 0.53
Expiration date	Nov. 30, 2028
May 2023 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Outstanding	801,527	0
Exercise price of warrants	$ 0.8188
Expiration date	May 26, 2028
June 2023 Common Stock Warrants
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Outstanding	7,764,445	0
Exercise price of warrants	$ 1
Expiration date	Dec. 08, 2028
June 2023 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Outstanding	543,511	0
Exercise price of warrants	$ 1.4063
Expiration date	Jun. 06, 2028

Equity Purchase Agreement (Addi

Equity Purchase Agreement (Additional Information) (Details) $ in Millions	Jan. 24, 2022 USD ($)
Purchase Agreement [Member]
Defined Benefit Plan Disclosure [Line Items]
Other expense relating to the commitment fee	$ 0.8

Preferred Stock and Stockhold_3

Preferred Stock and Stockholders' Deficit - Additional Information (Detail) - USD ($)			3 Months Ended		6 Months Ended
	Sep. 30, 2022	Jan. 24, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Mar. 31, 2023	Dec. 31, 2022	Aug. 25, 2021	Aug. 24, 2021
Class Of Stock [Line Items]
Preferred Stock, Shares authorized			100,000,000		100,000,000			100,000,000
Preferred stock, par value			$ 0.0001		$ 0.0001			$ 0.0001
Proceeds from issuance of common stock - Registered direct offerings, net of issuance costs					$ 14,642,000	$ 0
Common Stock Value			$ 6,000		$ 6,000			$ 4,000
Preferred stock, shares outstanding			0		0			0
Proceeds from exercise of common stock options and warrants					$ 38,000	3,000
Stock options outstanding			11,678,262		11,678,262			8,738,880
Stock and Warrants Issued During Period, Value, Preferred Stock and Warrants					$ 19,214,827
Common stock, shares issued			61,765,616		61,765,616			41,990,383
Common Stock, Shares, Issued			61,765,616		61,765,616			41,990,383
Number of Option Outstanding,Granted					3,350,001
Share-based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit					$ 100
Increase in reserved shares, percentage					$ 110
No share purchases under the Purchase Agreement			0		0
Fair value of vested option					$ 2,700,000
Share-based Payment Arrangement, Expense			$ 1,200,000	$ 1,200,000	2,300,000	$ 2,100,000
Unrecognized compensation cost related to outstanding employee options					$ 6,500,000
Expected term (in years)					2 years 6 months
Unrecognized compensation cost related to outstanding nonemployee options					$ 1,100,000
Outstanding non employee expense expected period					1 year 2 months 12 days
Maximum [Member]
Class Of Stock [Line Items]
Expected term (in years)					6 years 1 month 6 days	6 years 1 month 6 days
Holder of More Than 10% [Member]
Class Of Stock [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit					$ 10
Purchase Agreement [Member]
Class Of Stock [Line Items]
Other expense relating to the commitment fee		$ 800,000
lincoln Park [Member]
Class Of Stock [Line Items]
Purchase Agreement		36 months
Initial Purchase Amount		$ 3,000,000
Initial purchase number of shares		557,610
Shares issued, commitment shares		142,939
lincoln Park [Member] | Maximum [Member]
Class Of Stock [Line Items]
Available for sales of common shares under the facility		$ 50,000,000
lincoln Park [Member] | Regular Purchase [Member]
Class Of Stock [Line Items]
Trading volume percentage		25%
Percentage of common shares outstanding prior to the execution of purchase agreement		97%
Atm Offering Program Member
Class Of Stock [Line Items]
Payments Of Commission Percentage	3%
Proceeds from exercise of common stock options and warrants					$ 200,000
Shares Issued Price Per Share			$ 0.56		$ 0.56
Common stock, shares issued			410,836		410,836
Temporary equity underwriting discounts, commissions and fees					$ 100,000
Common Stock, Shares, Issued			410,836		410,836
Atm Offering Program Member | Maximum [Member]
Class Of Stock [Line Items]
Common Stock Value							$ 15,000,000
2013, Equity Incentive Plan
Class Of Stock [Line Items]
Stock options outstanding			3,314,227		3,314,227				3,920,657
Number of shares reserved for future issuance			0		0
Shares grants			0		0
2021, Equity Incentive Plan
Class Of Stock [Line Items]
Shares authorized			11,153,615		11,153,615
Shares purchased for award					8,948,410
Number of shares reserved for future issuance			2,789,580		2,789,580
Shares grants			2,789,580		2,789,580
2021 Employee Stock Purchase Plan [Member]
Class Of Stock [Line Items]
Shares fair market value percentage										85%
Common stock, shares issued			93,562		93,562
Share-Based Compensation Arrangement by Share-Based Payment Award, Percentage of Increase in Reserved Shares										1%
Number of shares reserved for future issuance			1,524,183		1,524,183					880,000
Shares grants			1,524,183		1,524,183					880,000
Common Stock, Shares, Issued			93,562		93,562
2021 Employee Stock Purchase Plan [Member] | Maximum [Member]
Class Of Stock [Line Items]
Number of shares reserved for future issuance										15,000,000
Shares grants										15,000,000
June 2023 Registered Direct Offering
Class Of Stock [Line Items]
Amortization Of Sales Commissions					$ 900,000
Net Proceed			$ 7,800,000		7,800,000
Proceeds from exercise of common stock options and warrants					$ 8,700,000
Shares Issued Price Per Share			$ 1.125		$ 1.125
Common stock, shares issued			5,950,000		5,950,000
Common Stock, Shares, Issued			5,950,000		5,950,000
May 2023 Registered Direct Offering
Class Of Stock [Line Items]
Amortization Of Sales Commissions					$ 800,000
Net Proceed			$ 6,700,000		6,700,000
Proceeds from exercise of common stock options and warrants					$ 7,500,000
Shares Issued Price Per Share			$ 0.655		$ 0.655
Common stock, shares issued			4,700,000		4,700,000
Common Stock, Shares, Issued			4,700,000		4,700,000
Common Stock [Member] | lincoln Park [Member]
Class Of Stock [Line Items]
Ownership percentage		4.99%
Common Stock [Member] | lincoln Park [Member] | Maximum [Member]
Class Of Stock [Line Items]
Purchase shares		30,000
Common Stock [Member] | lincoln Park [Member] | Purchase Agreement [Member]
Class Of Stock [Line Items]
Price per share		$ 6.42
Percentage of common shares outstanding prior to the execution of purchase agreement		19.99%
Aggregate number of common shares		8,133,926
Common Stock [Member] | lincoln Park [Member] | Regular Purchase [Member]
Class Of Stock [Line Items]
Regular Purchase, Description		The Regular Purchase Amount may be increased as follows: to up to 50,000 shares if the closing price is not below $5.00, and up to 75,000 shares if the closing price is not below $10.00.
Committed obligation amount		$ 2,500,000,000
Common Stock [Member] | lincoln Park [Member] | Regular Purchase [Member] | Maximum [Member]
Class Of Stock [Line Items]
Purchase shares					30,000
Common Stock [Member] | 2021 Employee Stock Purchase Plan [Member]
Class Of Stock [Line Items]
Stock Issued During Period, Shares, Employee Stock Purchase Plans					27,428
Employee Option [Member]
Class Of Stock [Line Items]
Weighted-average grant date fair value					$ 0.35
H.C. Wainwright & Co [Member] | Private Placement [Member] | June 2023 Registered Direct Offering
Class Of Stock [Line Items]
Gross Proceed			7%		7%
Managemengt fees percentage			1%		1%
Costs and Expenses					$ 50,000,000
Clearing fees					$ 15,950,000
H.C. Wainwright & Co [Member] | Private Placement [Member] | June 2023 Placement Agent Warrants
Class Of Stock [Line Items]
Gross Proceed			7%		7%
H.C. Wainwright & Co [Member] | Private Placement [Member] | May 2023 Registered Direct Offering
Class Of Stock [Line Items]
Gross Proceed			7%		7%
Managemengt fees percentage			1%		1%
Costs and Expenses					$ 75,000,000
Clearing fees					$ 15,950,000
H.C. Wainwright & Co [Member] | Private Placement [Member] | May 2023 Placement Agent Warrants
Class Of Stock [Line Items]
Gross Proceed			7%		7%

Preferred Stock and Stockhold_4

Preferred Stock and Stockholders Deficit - Summary of Option Activity Under the Company's Plans (Detail) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares
Equity [Abstract]
Number of Option Outstanding,Beginning balance | shares	8,738,880
Number of Option Outstanding,Granted | shares	3,350,001
Number of Option Outstanding,Exercised | shares	(56,008)
Number of Option Outstanding,Cancelled | shares	(354,611)
Number of Option Outstanding,Ending balance | shares	11,678,262	8,738,880
Number of Option Exercisable | shares	5,681,498
Weighted Average Exercise Price,Beginning balance | $ / shares	$ 2.73
Weighted Average Exercise Price,Granted | $ / shares	0.49
Weighted average exercise price,Exercised | $ / shares	0.52
Weighted average exercise price,Cancelled | $ / shares	2.1
Weighted Average Exercise Price,Ending balance | $ / shares	2.12	$ 2.73
Weighted Average Exercise Price,Exercisable | $ / shares	$ 2.4
Weighted- Average Remaining Contractual Term,Beginning balance	7 years 8 months 12 days	7 years 4 months 24 days
Weighted- Average Remaining Contractual Term,Granted	9 years 7 months 6 days
Weighted- Average Remaining Contractual Term,Cancelled	7 years
Weighted- Average Remaining Contractual Term, Ending balance	7 years 8 months 12 days	7 years 4 months 24 days
Weighted- Average Remaining Contractual Term,Exercisable	6 years 1 month 6 days
Aggregate Intrinsic Value,Beginning balance | $	$ 0
Aggregate Intrinsic Value,Ending balance | $	1,375	$ 0
Aggregate Intrinsic Value,Exercisable | $	$ 228

Preferred Stock and Stockhold_5

Preferred Stock and Stockholders' Deficit - Schedule of assumptions used in the Black-Scholes option pricing model to determine the fair value of the stock option grants (Detail)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	2 years 6 months
Expected dividend yield	0%	0%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	3.60%	1.70%
Expected volatility	84%	82%
Expected term (in years)	5 years 3 months 18 days	5 years 2 months 12 days
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	4.10%	3.30%
Expected volatility	85%	86%
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days

Preferred Stock and Stockhold_6

Preferred Stock and Stockholders' Deficit - Summary of Common Stock Reserved for Future Issuance (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Class Of Stock [Line Items]
Stock options issued and outstanding	11,678,262	8,738,880
Placement agent warrants issued and outstanding	$ 1,345,038
Common stock warrants issued and outstanding	$ 19,214,827
Unvested Shares Held By Sponsors	300,000
Authorized for future stock awards or option grants	2,789,580
Authorized for future issuances under the ESPP	1,524,183
Total	47,866,880
Public Warrants Issued and Outstanding
Class Of Stock [Line Items]
Class of Warrant or Right, Outstanding	5,833,323	5,833,323
Private Placement Warrants Issued and Outstanding
Class Of Stock [Line Items]
Class of Warrant or Right, Outstanding	181,667	181,667
Common Stock [Member]
Class Of Stock [Line Items]
Stock options issued and outstanding	11,678,262
Earn-Out Shares
Class Of Stock [Line Items]
Earn-Out shares	5,000,000

Earn-Out Shares - Additional In

Earn-Out Shares - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Trading days required for entitlement of common stock			20 days
Consecutive trading days required for entitlement of common stock			30 days
Common stock price per share	$ 0.0001		$ 0.0001		$ 0.0001
Gain on change in fair value of earn-out liability			$ 0	$ 12,041
Common stock, shares issued	61,765,616		61,765,616		41,990,383
Earn-Out Shares [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Fair value of earn-out shares			$ 0.01		$ 0.01
Fair value of option holder Earn-out Shares	$ 7,900		$ 7,900
Gain on change in fair value of earn-out liability	0	$ 1,300	0	12,000
Share based compensation	0	$ 0	$ 0	$ 300
Share based compensation service period			4 months 9 days
Unrecognized compensation expense	0		$ 0
Estimated fair value of Earn-out Shares	$ 61,000		$ 61,000
Earn-Out Shares [Member] | Stockholders [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Common stock, shares issued	4,561,353		4,561,353		438,647
Earn-Out Shares [Member] | Effector Therapeutics Inc [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Business acquisition, equity interest issued or issuable, number of shares			5,000,000
Common stock price per share	$ 20		$ 20

Earn-Out Shares - Summary of Es

Earn-Out Shares - Summary of Estimated Fair Value of Earn-Out Shares (Detail) - Earn-Out Shares [Member]	Jun. 30, 2023 yr USD ($)	Dec. 31, 2022 yr USD ($)
Stock price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input | $	0.83	0.43
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	1.15	1.15
Risk-free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.054	0.048
Forecast period (in years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input | yr	0.02	0.06
Cost of equity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.20	0.20

Earn-Out Shares - Summary of Ac

Earn-Out Shares - Summary of Activity for Earn-Out Liability (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)
Series C Preferred Stock Warrant Liability [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, Beginning Balance	$ 40
Change in fair value	0
Fair value, Ending Balance	40
Earn- out Liability [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, Beginning Balance	6
Change in fair value	0
Fair value, Ending Balance	$ 6

License Agreements - Additional

License Agreements - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Aug. 31, 2021	Jul. 31, 2021
License Agreement Disclosure [Line Items]
Research and development	$ 4,881,000	$ 6,919,000	$ 11,490,000	$ 10,031,000
Regents of the University of California [Member]
License Agreement Disclosure [Line Items]
Payable in connection with the closing of the merger agreement					$ 1,000,000
Research and development			$ 15,000	$ 15,000
Regents of the University of California [Member] | Amendment to the License Agreement [Member]
License Agreement Disclosure [Line Items]
Payable in connection with the closing of the merger agreement						$ 1,000,000
Regents of the University of California [Member] | Amendment to the License Agreement [Member] | Certain Clinical and Regulatory Milestones [Member]
License Agreement Disclosure [Line Items]
Remaining milestone payments payable						$ 375,000

Research Collaboration and Li_2

Research Collaboration and License Agreement - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Dec. 31, 2019	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Research Collaboration And License Agreement [Line Items]
Performance obligation transaction price		$ 27,000		$ 27,000
Revenue from contract with customer excluding assessed tax		0	$ 2,011	0	$ 2,011
Based on License [Member]
Research Collaboration And License Agreement [Line Items]
Performance obligation transaction price		25,600		25,600
Based on Research Activities [Member]
Research Collaboration And License Agreement [Line Items]
Performance obligation transaction price		$ 1,400		1,400
Early Development and Regulatory Milestones [Member]
Research Collaboration And License Agreement [Line Items]
Upfront of milestones payment				80,000
Non Early Stage Development Milestones [Member] | Non Exercise of Co-Funding And Co-Promotion Option [Member]
Research Collaboration And License Agreement [Line Items]
Upfront of milestones payment				165,000
Non Early Stage Development Milestones [Member] | Exercise of Co-Funding And Co-Promotion Option [Member]
Research Collaboration And License Agreement [Line Items]
Upfront of milestones payment				70,000
Specified Sales Based Milestones [Member]
Research Collaboration And License Agreement [Line Items]
Upfront of milestones payment				$ 235,000
Pfizer [Member]
Research Collaboration And License Agreement [Line Items]
Upfront payment received	$ 15,000

DARPA Grant Revenue - Additiona

DARPA Grant Revenue - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2021	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Segment Reporting Revenue Reconciling Item [Line Items]
Allowable costs of reimbursable	$ 5,000
Reimbursement Amount	$ 5,000
Cooperative Agreement [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Revenues		$ 0	$ 2,000	$ 0	$ 2,000
Reimbursable for allowable costs						$ 5,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Sep. 30, 2021
Lessee, Lease, Description [Line Items]
Operating lease, payments	$ 17,000	$ 18,000	$ 30,000	$ 35,000
Lease term					3 years
Building [Member]
Lessee, Lease, Description [Line Items]
Operating lease, cost	$ 16,000	$ 16,000	$ 33,000	$ 33,000

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Supplemental Balance Sheet Information Related to Leases (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Assets
Operating lease right-of-use assets	$ 83	$ 111
Total right-of-use assets	83	111
Liabilities
Operating lease liabilities, current	69	60
Operating lease liabilities, non-current	25	60
Total operating lease liabilities	$ 94	$ 120

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Future Minimum Rental Payments for Operating Leases (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2023	$ 37
2024	62
Total remaining lease payments	99
Less: imputed interest	(5)
Total operating lease liabilities	94	$ 120
Less: current portion	(69)
Long-term operating lease liabilities	$ 25	$ 60
Weighted-average remaining lease term (in years)	1 year 3 months 29 days
Weighted-average discount rate	8%

Employee Benefits (Additional I

Employee Benefits (Additional Information) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)
Retirement Benefits [Abstract]
Defined Contribution Plan, Cost	$ 0

Subsequent Events - Additional

Subsequent Events - Additional Information (Details) $ in Millions	1 Months Ended
	Apr. 30, 2021 USD ($)
Subsequent Event [Line Items]
Reimbursement Amount	$ 5