0001628280-26-031671 | 10-Q | XBRL Viewer

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Common Stock and Net Loss Per Share - Summary of Earnings Per Share Pre-funded Warrants (Details) - shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Equity [Abstract]
Pre-funded warrants to purchase common stock (in shares)	11,916,079	7,220,794

Condensed Consolidated Statements of Stockholders’ Deficit - USD ($) $ in Thousands	Total	Pre-Funded Warrant	Series 1 Warrants	Series 2 Warrants	Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Pre-Funded Warrant	Additional Paid-in Capital Series 1 Warrants	Additional Paid-in Capital Series 2 Warrants	Accumulated Other Comprehensive Gain (Loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2024					55,594,131
Beginning balance at Dec. 31, 2024	$ (45,528)				$ 6	$ 512,515				$ 135	$ (558,184)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock upon exercise of stock options and employee stock purchase plan (in shares)					127,209
Issuance of common stock upon exercise of stock options and employee stock purchase plan	139					139
Stock-based compensation expense	2,692					2,692
Unrealized losses on marketable securities	(121)									(121)
Net loss	(18,834)										(18,834)
Ending balance (in shares) at Mar. 31, 2025					55,721,340
Ending balance at Mar. 31, 2025	$ (61,652)				$ 6	515,346				14	(577,018)
Beginning balance (in shares) at Dec. 31, 2025	56,657,329				56,657,329
Beginning balance at Dec. 31, 2025	$ (108,500)				$ 6	523,937				24	(632,467)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock from direct offering, net of offering costs (in shares)					2,030,314
Issuance of common stock from direct offering, net of offering costs	10,213					10,213
Issuance of pre-funded warrants from direct offering, net of offering costs		$ 27,271	$ 2,942	$ 9,226			$ 27,271	$ 2,942	$ 9,226
Issuance of common stock upon exercise of stock options and employee stock purchase plan (in shares)					22,847
Issuance of common stock upon exercise of stock options and employee stock purchase plan	89					89
Stock-based compensation expense	2,383					2,383
Unrealized losses on marketable securities	(157)									(157)
Net loss	$ (19,875)										(19,875)
Ending balance (in shares) at Mar. 31, 2026	58,710,490				58,710,490
Ending balance at Mar. 31, 2026	$ (76,408)				$ 6	$ 576,061				$ (133)	$ (652,342)

Leases (Tables)

3 Months Ended

Mar. 31, 2026

Leases [Abstract]

Summary of Lease Cost and Lease Details

The components of lease expense were as follows for the three months ended March 31, 2026 and 2025 (in thousands):


	Three Months Ended March 31,
		2026		2025
Operating lease cost		$	1,285	$	1,932
Variable lease cost		—		809
		$	1,285	$	2,741

Supplemental disclosure of cash flow information related to leases was as follows (in thousands):


	Three Months Ended March 31,
	2026		2025
Cash paid for amounts included in the measurement of operating lease liabilities	$	—	$	2,762
Asset acquired in finance lease	$	—	1,208

The weighted average remaining lease term and discount rate was as follows:


	March 31, 2026		December 31, 2025
Weighted-average remaining lease term—operating leases (in years)	9.4		9.7
Weighted-average discount rate—operating leases	7.24	%	7.24	%

Summary of Minimum Lease Payments

Future annual minimum lease payments under the Office Lease as of March 31, 2026 were as follows (in thousands):


Remainder of 2026 (nine months)	$	979
2027	4,280
2028	5,713
2029	6,774
2030	6,977
Thereafter	36,088
Total future minimum lease payments	60,811
Less: imputed interest	(18,453)
Less: lease incentives	(364)
Total operating lease liabilities	$	41,994

Summary of Balance Sheet Location


Included in the consolidated balance sheets (in thousands):	March 31, 2026
Current operating lease liabilities	$	1,863
Operating lease liabilities, net of current portion	40,131
Total operating lease liabilities	$	41,994

Leases - Summary of Supplemental Cash Flow Information Related to Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Leases [Abstract]
Cash paid for amounts included in the measurement of operating lease liabilities	$ 0	$ 2,762
Asset acquired in finance lease	$ 0	$ 1,208

Leases - Summary of Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Leases [Abstract]
Operating lease cost	$ 1,285	$ 1,932
Variable lease cost	0	809
Total	$ 1,285	$ 2,741

Segment Reporting - Additional Information (Details)	3 Months Ended
Segment Reporting - Additional Information (Details)	Mar. 31, 2026 segment
Segment Reporting [Abstract]
Number of operating segments	1
Number of reportable segments	1

Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2026	Apr. 30, 2026
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Transition Report	false
Entity File Number	001-39634
Entity Registrant Name	Foghorn Therapeutics Inc.
Entity Incorporation, State	DE
Entity Tax Identification Number	47-5271393
Entity Address, Street Name	99 Coolidge Avenue, Suite 500
Entity Address, City	Watertown
Entity Address, State	MA
Entity Address, Postal Zip Code	02472
City Area Code	617
Local Phone Number	586-3100
Title of each class	Common Stock, $0.0001 par value per share
Trading Symbol(s)	FHTX
Name of each exchange on which registered	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		58,713,922
Amendment Flag	false
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001822462
Current Fiscal Year End Date	--12-31

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Share-based Payment Arrangement
Stock-based compensation expense	$ 2,383	$ 2,692
Research and development expenses
Share-based Payment Arrangement
Stock-based compensation expense	993	1,150
General and administrative expenses
Share-based Payment Arrangement
Stock-based compensation expense	$ 1,390	$ 1,542

Common Stock and Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2026

Equity [Abstract]

Summary of Earnings Per Share, Basic and Diluted

The following pre-funded warrants outstanding at each period end were included in the basic and diluted net loss per share calculation:


	March 31,
	2026	2025
Pre-funded warrants to purchase common stock	11,916,079	7,220,794

Summary of Earnings Per Share Diluted Anti Dilutive Impact

The following common stock equivalents presented based on amounts outstanding at each period end have been excluded from the calculation of diluted net loss per share because including them would have had an anti-dilutive impact:


	March 31,
	2026	2025
Stock options to purchase common stock	13,835,670	10,785,630
Warrants to purchase common stock	7,470,009	18,445
	21,305,679	10,804,075

Commitments and Contingencies (Details) - Maximum - Stanford License Agreement $ in Millions	3 Months Ended
	Mar. 31, 2026 USD ($)
Loss Contingencies
Annual license maintenance fees	$ 0.1
Milestones payable upon event	$ 1.1

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Accrued Expenses and Other Current Liabilities

3 Months Ended

Mar. 31, 2026

Payables and Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

Accrued expenses consisted of the following (in thousands):


	March 31, 2026		December 31, 2025
Accrued external research and development expenses	$	4,316	$	4,194
Accrued employee compensation and benefits	1,514		5,921

Accrued professional fees	657		842

Other	437		400
	$	6,924	$	11,357

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2026	Dec. 31, 2025
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	175,000,000	175,000,000
Common stock, shares issued (in shares)	58,710,490	56,657,329
Common stock, shares outstanding (in shares)	58,710,490	56,657,329

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2026
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Common Stock and Net Loss Per Share

3 Months Ended

Mar. 31, 2026

Equity [Abstract]

Common Stock and Net Loss Per Share

Common Stock

Each share of common stock, par value $0.0001 per share (“Common Stock”), entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are not entitled to receive dividends, unless declared by the board of directors.

On January 9, 2026, the Company entered into securities purchase agreements (the “Purchase Agreements”) with certain leading life sciences investors (the “Investors”), relating to the issuance and sale of 2,030,314 shares of its Common Stock and, in lieu of Common Stock, pre-funded warrants to purchase 5,421,250 shares of Common Stock (the “Pre-Funded Warrants”). The Company sold the shares of Common Stock and Pre-Funded Warrants together with two series of warrants, Series 1 Warrants and Series 2 Warrants, to purchase an aggregate of 7,451,564 shares of the Common Stock (the “Series Warrants”). The Pre-Funded Warrants were exercisable immediately upon issuance at an initial exercise price of $0.0001 per share and have a term of 20 years. The shares of Common Stock, or Pre-Funded Warrants, and the accompanying Series Warrants were immediately separable and were issued separately, but they were purchased together in the offering.

The offering price for the shares of Common Stock is $6.71 per share (or $6.7099 for each Pre-Funded Warrant, which equals the price per share of the Common Stock less the exercise price of the Pre-Funded Warrants). The aggregate gross proceeds to the Company from this offering were approximately $50.0 million before any offering expenses, and excluding any proceeds the Company may receive upon exercise of the Pre-Funded Warrants and Series Warrants. The Company incurred offering costs of approximately $0.3 million, which were treated as a reduction to equity. No underwriter or placement agent participated in the offering. As the Pre-funded Warrants are indexed to the Company’s common stock (and otherwise meet the requirements to be classified in equity), the Pre-Funded Warrants were classified as a component of permanent equity on the Company’s condensed consolidated balance sheets and statements of stockholder’s deficit.

The Series Warrants are also immediately exercisable. Each of the 3,725,782 Series 1 Warrants have an initial exercise price of $13.42 per share of Common Stock, subject to certain customary anti-dilution adjustments, and expires on June 30, 2027. Each of the 3,725,782 Series 2 Warrants have an initial exercise price of $20.13 per share of Common Stock, subject to certain customary anti-dilution adjustments, and expires on December 31, 2030. For the Series Warrants, the Investor may elect to receive, in lieu of shares of Common Stock, pre-funded warrants to purchase an equivalent number of shares of Common Stock.

If, prior to the expiration date of the Series Warrant, the Company sells additional capital stock or derivative securities convertible into or exercisable for capital stock (other than Exempted Securities as defined by the Series Warrant) in one or more related transactions primarily for the purpose of raising capital at a Weighted-Average Price (as described below) below $13.42 per share, then the initial exercise price of the Series Warrants will be automatically reset upon exercise to an exercise price (the “Adjusted Exercise Price”) that is the midpoint between the initial exercise price and the lowest Weighted-Average Price per share at which the Company sells capital stock or derivative securities convertible into or exercisable for capital stock in a subsequent offering prior to the exercise date; provided, however, that the Adjusted Exercise Price will not be reduced below $6.71 per share. The Weighted-Average Price shall be calculated as the weighted-average common stock equivalent price of the equity securities sold in such transaction(s) (excluding any derivative securities with an exercise or conversion price that is above the closing sale price as of the time of pricing such offering(s)). In no event will the exercise price for the Series Warrants be adjusted more than once pursuant to this adjustment mechanism.

The Series Warrants (and the Pre-Funded Warrants) may not be exercised by the holder to the extent that the holder, together with its affiliates, would beneficially own, after such exercise more than 9.99% of the shares of the Company’s common stock then outstanding (subject to the right of the holder to increase or decrease such beneficial ownership limitation upon notice to the Company, provided that such limitation cannot exceed 19.99%) and provided that any increase in the beneficial ownership

limitation shall not be effective until 61 days after such notice is delivered. As of March 31, 2026, no Pre-Funded or Series Warrants have been exercised.

The Series Warrants are also indexed to the Company’s common stock (and otherwise meet the requirements to be classified in equity) and were classified as a component of permanent equity on the Company’s condensed consolidated balance sheets and statements of stockholder’s deficit.

Because each of the instruments issued are classified within permanent equity, The Company allocated the financing proceeds among the Common Stock, Pre-Funded Warrants, and Series Warrants based on each instrument’s relative fair value. The Company valued the Series Warrants at issuance using Monte Carlo Simulation model and determined the fair value of the 7,451,564 Series Warrants to be $12.2 million. The key inputs to the valuation model included the weighted average volatility of 88.2% and the weighted average expected term of 4.13 years.

On April 15, 2022, the Company entered into a sales agreement (the “Sales Agreement”) with Cowen and Company, LLC (“Cowen”) with respect to an at-the-market offering (the “ATM Offering”) pursuant to which the Company, at its discretion, may offer and sell shares of its Common Stock having an aggregate offering price of up to $200.0 million from time to time through Cowen as its sales agent. Sales of Common Stock through Cowen, if any, will be made by any method permitted by law deemed to be an “at the market offering” as defined in Rule 415(a)(4) under the Securities Act of 1933, as amended. The Company will pay Cowen a commission of up to 3.0% of the gross sales price of any Common Stock sold through Cowen under the Sales Agreement.

On March 20, 2025, the Company and TD Securities (USA) LLC, as successor to Cowen (“TD Cowen”) entered into amended the sales agreement (the “Amended Sales Agreement”), which, among other things, reduced the amount of shares of Common Stock that may be sold under the ATM Offering to up to $100 million of shares of Common Stock.

During the three months ended March 31, 2026, the Company issued and sold no shares of its Common Stock under the ATM Facility.

Net Loss Per Share

The following pre-funded warrants outstanding at each period end were included in the basic and diluted net loss per share calculation:


	March 31,
	2026	2025
Pre-funded warrants to purchase common stock	11,916,079	7,220,794

During the three months ended March 31, 2026 and 2025, no pre-funded warrants were exercised.


	March 31,
	2026	2025
Stock options to purchase common stock	13,835,670	10,785,630
Warrants to purchase common stock	7,470,009	18,445
	21,305,679	10,804,075

- Definition

The entire disclosure for equity.

+ References

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+ Details

Summary of Significant Accounting Policies	3 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2026
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies The accounting policies of the Company are set forth in Note 2, Summary of Significant Accounting Policies, to the consolidated financial statements contained in the Company’s 2025 Annual Report on Form 10-K, and the accounting policies followed by the Company for interim financial reporting are consistent with the accounting policies therein. Recently Issued Accounting Pronouncements From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that the Company adopts as of the specified effective date. In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures, which is intended to improve disclosures about a public company’s expenses including the disclosure of certain expenses included and aggregated in captions such as cost of sales, selling general & administrative and research and development expenses on the consolidated financial statements on an interim and annual basis. The standard is effective for annual periods beginning after December 15, 2026 and interim periods within annual periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating the impact of the standard on the presentation of its condensed consolidated financial statements and footnotes.

Segment Reporting

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Segment Reporting

Operating segments are defined as components of an entity for which separate discrete financial information is made available and that is regularly evaluated by the chief operating decision maker (“CODM”) in making decisions regarding resource allocation and assessing performance. The Company manages its operations as a single segment (the “Segment”) for the purposes of assessing performance and making operating decisions. The CODM of the Segment is the Company’s chief executive officer. The Segment is focused on pioneering the discovery and development of a new class of medicines targeting genetically determined dependencies within the chromatin regulatory system. The Segment’s revenue is derived entirely from the recognition of deferred revenue related to our collaboration agreement upfront and milestone payment and funds received under the Lilly SPA (see Note 8, Collaboration Agreement).

The CODM assesses the performance of the Segment and decides how to allocate resources based on net loss that is reported on the condensed consolidated statements of operations and comprehensive loss. Further, the following represents information about segment revenue, segment loss and significant segment expenses (in thousands):


	Three Months Ended March 31,
		2026		2025
Collaboration revenue		$	3,267	$	5,952
Less:
Research and development:
Personnel expenses		5,739		6,344
FHD-286		192		991
Lilly partnered programs		2,290		4,625
Proprietary programs		5,996		3,447
Research and development operating and administrative costs		1,261		1,667
General and administrative:
Personnel expenses		3,017		2,927
External expenses		1,996		2,072
Facilities and IT related expenses, net of sublease income		1,761		1,877
Other expenses(1)		2,632		3,528

Plus:
Interest income		1,742		2,692
Net loss		$	(19,875)	$	(18,834)

(1) Inclusive of $2.4 million and $2.7 million of stock compensation expense for the three months ended March 31, 2026 and 2025, respectively; $0.2 million and $0.8 million of depreciation and amortization expense for the three months ended March 31, 2026 and 2025, respectively

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details

Property and Equipment, Net

3 Months Ended

Mar. 31, 2026

Property, Plant and Equipment [Abstract]

Property and Equipment, Net

Property and equipment, net consisted of the following (in thousands):


	March 31, 2026		December 31, 2025
Laboratory equipment	$	8,070	$	8,035
Furniture and fixtures	839		839
Computer equipment and software	46		46


	8,955		8,920
Less: Accumulated depreciation and amortization	(7,243)		(7,005)
	$	1,712	$	1,915

Depreciation and amortization expense was $0.2 million and $0.8 million for the three months ended March 31, 2026 and 2025, respectively.

Nature of Business, Going Concern and Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net loss	$ (19,875)	$ (18,834)
Accumulated deficit	$ 652,342		$ 632,467

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Related Parties	3 Months Ended
Related Parties	Mar. 31, 2026
Related Party Transactions [Abstract]
Related Parties	Related Parties In October 2015, the Company entered into a five-year consulting agreement with a scientific founder of the Company who is also a shareholder. This agreement was amended and extended to January 1, 2027 and is subject to automatic one-year renewal terms until terminated if notice is provided more than 30 days before the current end of term date. During the three months ended March 31, 2026 and 2025, the Company paid the scientific founder a de minimis amount. As of March 31, 2026 and December 31, 2025, the Company had no accounts payable due to the scientific founder. On December 10, 2021, we entered into the Lilly Collaboration Agreement with Lilly. Concurrent with the Lilly Collaboration Agreement the Company also entered into a stock purchase agreement with Lilly (the “Lilly SPA”) where the Company issued and sold Lilly 4,000,000 shares of our Common Stock at a price of $20.00 per share, making them a 5% or greater shareholder in the Company for the three months ended March 31, 2026 and 2025. We are obligated to make certain payments to Lilly pursuant to the Lilly Collaboration Agreement. During the three months ended March 31, 2026 and 2025, the Company paid Lilly $1.0 million and $0.6 million, respectively. As of March 31, 2026 and December 31, 2025, the Company had a payable of $1.0 million due to Lilly. On January 9, 2026, funds affiliated with Flagship Pioneering, Inc. (“Flagship”), a 5% or greater shareholder in the Company, participated in the January 2026 Offering, purchasing pre-funded warrants to purchase 2,235,468 shares of its Common Stock at a public offering price of $6.71 per pre-funded warrant, with an exercise price of $0.0001 per share of each pre-funded warrant. The Company sold the pre-funded Warrants together with two series of warrants, Series 1 Warrants and Series 2 Warrants, to purchase an aggregate of 2,235,468 shares of the Common Stock (See Note 6 for additional information on the Series Warrants). Flagship’s participation in the January 2026 Offering resulted in total gross proceeds to the Company of $15.0 million. On January 9, 2026, BVF Partners LP (“BVF”), a 5% or greater shareholder in the Company, participated in the January 2026 Offering, purchasing 540,000 shares of its Common Stock at a public offering price of $6.71 per share as well as pre-funded warrants to purchase 3,185,782 shares of its Common Stock at a public offering price of $6.7099 per pre-funded warrant, with an exercise price of $0.0001 per share of each pre-funded warrant. The Company sold the shares of Common Stock and pre-funded warrants together with two series of warrants, Series 1 Warrants and Series 2 Warrants, to purchase an aggregate of 3,725,782 shares of the Common Stock (See Note 6 for additional information on the Series Warrants). BVF’s participation in the January 2026 Offering resulted in total gross proceeds to the Company of $25.0 million. On January 9, 2026, Deerfield Management Co. LP (“Deerfield”), a 5% or greater shareholder in the Company, participated in the January 2026 Offering, purchasing 745,156 shares of its Common Stock at a public offering price of $6.71 per share. The Company sold the shares of Common Stock together with two series of warrants, Series 1 Warrants and Series 2 Warrants, to purchase an aggregate of 745,156 shares of the Common Stock (See Note 6 for additional information on the Series Warrants). Deerfield’s participation in the January 2026 Offering resulted in total gross proceeds to the Company of $5.0 million. On January 9, 2026, FMR LLC (“FMR”), a 5% or greater shareholder in the Company, participated in the January 2026 Offering, purchasing 745,158 shares of its Common Stock at a public offering price of $6.71 per share. The Company sold the shares of Common Stock together with two series of warrants, Series 1 Warrants and Series 2 Warrants, to purchase an aggregate of 745,158 shares of the Common Stock (See Note 6 for additional information on the Series Warrants). FMR’s participation in the January 2026 Offering resulted in total gross proceeds to the Company of $5.0 million.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-5

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(e))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

+ Details

Leases - Summary of Minimum Lease Payment (Details) $ in Thousands	Mar. 31, 2026 USD ($)
Lessee, Operating Lease, Liability, Payment, Due
Remainder of 2026 (nine months)	$ 979
2027	4,280
2028	5,713
2029	6,774
2030	6,977
Thereafter	36,088
Total future minimum lease payments	60,811
Less: imputed interest	(18,453)
Less: lease incentives	(364)
Total operating lease liabilities	$ 41,994

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2026
Accounting Policies [Abstract]
Basis of presentation	Basis of presentation The Company’s unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the United States Securities and Exchange Commission for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. All intercompany accounts and transactions have been eliminated in consolidation. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that the Company adopts as of the specified effective date. In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures, which is intended to improve disclosures about a public company’s expenses including the disclosure of certain expenses included and aggregated in captions such as cost of sales, selling general & administrative and research and development expenses on the consolidated financial statements on an interim and annual basis. The standard is effective for annual periods beginning after December 15, 2026 and interim periods within annual periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating the impact of the standard on the presentation of its condensed consolidated financial statements and footnotes.

Leases - Summary of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Leases [Abstract]
Current operating lease liabilities	$ 1,863	$ 923
Operating lease liabilities, net of current portion	40,131	$ 40,347
Total operating lease liabilities	$ 41,994

Leases - Summary of Weighted-Average Remaining Lease Term and Discount Rate Leases (Details)	Mar. 31, 2026	Mar. 31, 2025
Leases [Abstract]
Weighted-average remaining lease term—operating leases (in years)	9 years 4 months 24 days	9 years 8 months 12 days
Weighted-average discount rate—operating leases	7.24%	7.24%

Property and Equipment, Net (Tables)

3 Months Ended

Mar. 31, 2026

Property, Plant and Equipment [Abstract]

Summary of Property and Equipment Net

Property and equipment, net consisted of the following (in thousands):


	March 31, 2026		December 31, 2025
Laboratory equipment	$	8,070	$	8,035
Furniture and fixtures	839		839
Computer equipment and software	46		46


	8,955		8,920
Less: Accumulated depreciation and amortization	(7,243)		(7,005)
	$	1,712	$	1,915

Marketable Securities and Fair Value Measurements

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Marketable Securities and Fair Value Measurements

As of March 31, 2026, available for sale marketable securities by security type consisted of (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value


Commercial paper (due within one year)	57,314		—		(60)		57,254
Corporate notes and bonds (due within one year)	33,771		—		(61)		33,710

Corporate notes and bonds (due after one year through two years)	5,016		—		(12)		5,004
Total	$	96,101	$	—	$	(133)	$	95,968

As of December 31, 2025, available for sale marketable securities by security type consisted of (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value

U.S. government agencies (due within one year)	1,500		—		—		1,500
Commercial paper (due within one year)	35,286		4		(3)		35,287
Corporate notes and bonds (due within one year)	41,208		23		—		41,231

Total	$	77,994	$	27	$	(3)	$	78,018

The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands):


	Fair Value Measurements at March 31, 2026 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	79,991	$	—	$	—	$	79,991

Commercial paper	—		7,467		—		7,467
Marketable securities:


Commercial paper	—		57,254		—		57,254
Corporate notes and bonds	—		38,714		—		38,714
Total	$	79,991	$	103,435	$	—	$	183,426
	Fair Value Measurements at December 31, 2025 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	56,357	$	—	$	—	$	56,357

Commercial paper	—		24,227		—		24,227
Marketable securities:

U.S. government agencies	—		1,500		—		1,500
Commercial paper	—		35,287		—		35,287
Corporate notes and bonds	—		41,231		—		41,231
Total	$	56,357	$	102,245	$	—	$	158,602

For the three months ended March 31, 2026 and 2025, there were no transfers between Level 1, Level 2 and Level 3.

Related Parties (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended
	Jan. 09, 2026	Dec. 10, 2021	Oct. 31, 2015	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Related Party Transaction
Accounts payable				$ 3,317		$ 4,266
Accrued expenses and other current liabilities				$ 6,924		$ 11,357
Common stock, par value (in dollars per share)				$ 0.0001		$ 0.0001
Related Party \| Foghorn Therapeutics \| Flagship Pioneering, Inc.
Related Party Transaction
Equity method investment, ownership percentage	5.00%
Related Party \| Foghorn Therapeutics \| BVF Partners LP
Related Party Transaction
Equity method investment, ownership percentage	5.00%
Related Party \| Foghorn Therapeutics \| Deerfield Management Co. LP
Related Party Transaction
Equity method investment, ownership percentage	5.00%
Related Party \| Foghorn Therapeutics \| FMR LLC
Related Party Transaction
Equity method investment, ownership percentage	5.00%
Related Party \| Eli Lilly \| Lilly Collaboration Agreement
Related Party Transaction
Related party transaction, amounts of transaction				$ 1,000	$ 600
Accrued expenses and other current liabilities				$ 1,000		$ 1,000
Related Party \| Eli Lilly \| Share Purchase Agreement
Related Party Transaction
Sale of stock, number of shares issued in transaction (in shares)		4,000,000
Sale of stock issue price per share (in dollars per share)				$ 20.00	$ 20.00
Related Party \| Flagship Pioneering, Inc. \| January 2026 Offering
Related Party Transaction
Class of warrant or right, number of securities called by warrants or rights (in shares)	2,235,468
Exercise price of warrant (in dollars per share)	$ 6.71
Common stock, par value (in dollars per share)	$ 0.0001
Proceed from issuance of stock	$ 15,000
Related Party \| BVF Partners LP \| January 2026 Offering
Related Party Transaction
Class of warrant or right, number of securities called by warrants or rights (in shares)	540,000
Exercise price of warrant (in dollars per share)	$ 6.71
Common stock, par value (in dollars per share)	$ 0.0001
Proceed from issuance of stock	$ 25,000
Related Party \| BVF Partners LP \| Prefunded Warrants
Related Party Transaction
Class of warrant or right, number of securities called by warrants or rights (in shares)	3,185,782
Exercise price of warrant (in dollars per share)	$ 6.7099
Related Party \| BVF Partners LP \| Series Warrants
Related Party Transaction
Class of warrant or right, number of securities called by warrants or rights (in shares)	3,725,782
Related Party \| Deerfield Management Co. LP \| January 2026 Offering
Related Party Transaction
Class of warrant or right, number of securities called by warrants or rights (in shares)	745,156
Exercise price of warrant (in dollars per share)	$ 6.71
Proceed from issuance of stock	$ 5,000
Related Party \| FMR LLC \| January 2026 Offering
Related Party Transaction
Class of warrant or right, number of securities called by warrants or rights (in shares)	745,158
Exercise price of warrant (in dollars per share)	$ 6.71
Proceed from issuance of stock	$ 5,000
Scientific Founder \| Related Party
Related Party Transaction
Service agreement term			5 years
Service agreement, renewal term			1 year
Accounts payable				$ 0		$ 0

Leases - Additional Information (Details) $ in Millions	3 Months Ended
Leases - Additional Information (Details) $ in Millions	Mar. 31, 2025 USD ($)
Leases [Abstract]
Sublease income recorded as other income	$ 1.4

Collaboration Agreement (Details) $ in Thousands	1 Months Ended	3 Months Ended
Collaboration Agreement (Details) $ in Thousands	Dec. 31, 2021 USD ($) program target	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)	Sep. 30, 2023
Collaborative Arrangement and Arrangement Other than Collaborative
Revenue		$ 3,267	$ 5,952
Accrued expenses and other current liabilities		6,924		$ 11,357
Eli Lilly
Collaborative Arrangement and Arrangement Other than Collaborative
Number of programs \| program	6
Number of targets \| target	5
Cost sharing rate	50.00%				50.00%
Deferred revenue		245,900
Eli Lilly \| Related Party
Collaborative Arrangement and Arrangement Other than Collaborative
Revenue		3,300	$ 6,000
Eli Lilly \| Related Party \| Lilly Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative
Accrued expenses and other current liabilities		$ 1,000		$ 1,000
Eli Lilly \| Sales Based Milestone
Collaborative Arrangement and Arrangement Other than Collaborative
Amount receivable for achievement of milestones	$ 180,000
Optout milestone receivable upon achievement	360,000
Eli Lilly \| Maximum \| Research Development and Regulatory
Collaborative Arrangement and Arrangement Other than Collaborative
Amount receivable for achievement of milestones	10,000
Optout milestone receivable upon achievement	$ 70,000
Eli Lilly \| Joint Programs
Collaborative Arrangement and Arrangement Other than Collaborative
Number of programs \| program	2
Number of targets \| target	1
Eli Lilly \| Discovery Programs
Collaborative Arrangement and Arrangement Other than Collaborative
Number of additional targets \| target	3

Collaboration Agreement	3 Months Ended
Collaboration Agreement	Mar. 31, 2026
Collaboration Agreement [Abstract]
Collaboration Agreement	Collaboration Agreement Lilly Collaboration Agreement and Stock Purchase Agreement In December 2021, the Company entered into a collaboration agreement (the “Lilly Collaboration Agreement”) with Eli Lilly and Company (“Lilly”) to create novel oncology medicines by applying Foghorn’s proprietary Gene Traffic Control platform. The collaboration includes a co-development and co-commercialization agreement for the Company’s selective SMARCA2 (BRM) oncology target, consisting of two programs, and one additional undisclosed oncology target (collectively, the “Joint Programs”). The collaboration also includes three additional discovery targets or programs (collectively, the “Discovery Programs”) for a total of six programs directed at five targets. With respect to the Joint Programs, the Company will lead discovery and early research activities through the successful completion of dose finding toxicity studies for the identified compound, while Lilly will lead development and commercialization activities of the identified compound with participation from the Company in development activities and 50% cost sharing until registrational clinical trials. The Company and Lilly may jointly develop and commercialize the Joint Program compound though the Company may, in its sole discretion, opt-out on a program-by-program basis of further participation in the development and commercialization efforts prior to the first registrational clinical trial. If the Company does not opt-out, Lilly and the Company will continue to share in the costs to further develop and commercialize the Joint Program compound on a worldwide basis, equally share in the U.S. profits on product sales, subject to certain adjustments and receive royalties on sales outside of the United States (“Ex-U.S.”) at royalty rates ranging from low double digits to high twenties. If the Company opts-out of further development and commercialization efforts, it will have no further obligations to share in the development and commercialization costs, will receive royalties rather than profit share on U.S. sales and will receive royalties at a lower rate on Ex-U.S. sales. With respect to the Discovery Programs, the Company will lead discovery and early research activities through the successful completion of dose finding toxicity studies for the identified compounds. The Company may, in its sole discretion, opt-in on a program-by-program basis after the successful completion of dose finding toxicity to participate in the further development and commercialization efforts of the Discovery Program compounds. If the Company opts-in to the development and commercialization of the Discovery Program compounds, it will be eligible to receive milestone payments of up to $10.0 million per program upon specified research and development milestones and up to $180.0 million per program upon achievement of specified regulatory and commercial milestones and will also be eligible to share in the U.S. profits at pre-determined percentages on product sales. The Company would also be eligible to receive tiered Ex-U.S. royalty rates, calculated on a product-by-product and country-by-country basis, on net sales outside of the United States, if any, ranging from low single digits to low double digits, but less then teens. If the Company does not opt-in to further development and commercialization efforts for the Discovery Programs, it will be eligible to receive milestone payments of up to $70.0 million per program upon specified research and development milestones and up to $360.0 million per program upon achievement of specified regulatory and commercial milestones per approved product, if any. The Company would also be eligible to receive tiered royalties on net sales of products worldwide at royalty rates ranging from low single digits to low double digits, but less than teens. Lilly has the right to make substitutions for each of the five targets during the research term of each program, subject to certain limitations. Pursuant to the Lilly Collaboration Agreement, the Company will also participate in joint decision-making through the joint steering committee and subcommittees. Unless terminated earlier, the Lilly Collaboration Agreement will continue on a product-by-product basis until the expiration of all royalty obligations under the Lilly Collaboration Agreement and when neither the Company nor Lilly is developing, commercializing or manufacturing any product under the Lilly Collaboration Agreement. The Company or Lilly may terminate the Lilly Collaboration Agreement upon an uncured material breach by the other party. Lilly may also terminate the Lilly Collaboration Agreement in its entirety or on a target-by-target, program-by-program or product-by-product basis for any reason upon certain notice to the Company. The Company determined that (1) the research activities performed by the Company for both the Joint Programs and the Discovery Programs (2) the development activities and cost sharing for the Joint Program development efforts after dose finding toxicity until registrational clinical trials (3) the research, development, manufacture and commercialization licenses and (4) service on the joint steering committee and subcommittees represent a single performance obligation under the Lilly Collaboration Agreement. The Company determined that Lilly cannot benefit from the licenses separately from the research activities, the development activities until registrational clinical trials and participation on the joint steering committee and subcommittees because these services are specialized and rely on the Company’s expertise such that these activities are highly interrelated and therefore not distinct. Accordingly, the promised goods and services represent one combined performance obligation, and the entire transaction price was allocated to that single combined performance obligation. The performance obligation will be satisfied over time as the Company performs the research activities, participates and shares in the cost of the development activities for the Joint Programs and participates in a joint steering committee and subcommittees to oversee these activities. The Company’s options to share in further development and commercialization efforts via its opt-in/opt-out rights will be assessed and accounted for as separate units of accounting under the relevant guidance if, and when, such options are exercised by the Company. During the third quarter of 2023, the Company transitioned the SMARCA2 (BRM) Selective inhibitor, FHD-909, into development activities for which Lilly leads and the Company participates and shares in 50% of the costs until at least registrational trials. Costs incurred will continue to be included in research and development expenses on the condensed consolidated statements of operations and comprehensive loss. As of March 31, 2026, the aggregate amount of the transaction price related to the unsatisfied portion of the performance obligation was $245.9 million, which is expected to be recognized as revenue through 2029 or beyond depending on the timing of certain clinical development activities. The Company does not expect collaboration revenue to be recognized evenly over this period as it will be recognized on a percentage of completion basis (using cost-to-cost method) as the Company performs the research and development activities and participates on the joint steering committee and subcommittees, which will likely vary from period to period. In estimating the total costs to satisfy its single performance obligation pursuant to the Lilly Collaboration Agreement, the Company is required to make significant estimates including the expected time and expected costs to fulfill the performance obligation. If estimates of the total estimated cost change, or if contract amendments change the scope of the performance obligations, the impacts could be material. The cumulative effect of revisions to the total estimated costs to complete the Company’s single performance obligation will be recorded in the period in which the changes are identified, and amounts can be reasonably estimated. A significant change in these assumptions and estimates could have a material impact on the timing and amount of revenue recognized in future periods and the classification of deferred revenue between short-term and long-term. For the three months ended March 31, 2026 and 2025, the Company recorded $3.3 million and $6.0 million, respectively, of revenue under the Lilly Collaboration Agreement, which was included in deferred revenue at the beginning of the respective periods. As of March 31, 2026 and December 31, 2025, the Company had a payable to Lilly of $1.0 million, recorded in accrued expenses and other current liabilities on the Company’s condensed consolidated balance sheets.

Segment Reporting - Summary of Reconciled Expense of Consolidated Statement of Operations and Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Collaboration revenue	$ 3,267	$ 5,952
Research and development:
Research and development expense	18,259	21,626
General and administrative:
Interest income	1,742	2,692
Net loss	(19,875)	(18,834)
Stock-based compensation expense	2,383	2,692
Depreciation and amortization expense	238	827
The Segment
Segment Reporting Information [Line Items]
Collaboration revenue	3,267	5,952
General and administrative:
Personnel expenses	3,017	2,927
External expenses	1,996	2,072
Facilities and IT related expenses, net of sublease income	1,761	1,877
Other expenses	2,632	3,528
Interest income	1,742	2,692
Net loss	(19,875)	(18,834)
Stock-based compensation expense	2,400	2,700
Depreciation and amortization expense	200	800
Personnel expenses \| The Segment
Research and development:
Research and development expense	5,739	6,344
FHD-286 \| The Segment
Research and development:
Research and development expense	192	991
Lilly partnered programs \| The Segment
Research and development:
Research and development expense	2,290	4,625
Proprietary programs \| The Segment
Research and development:
Research and development expense	5,996	3,447
Research and development operating and administrative costs \| The Segment
Research and development:
Research and development expense	$ 1,261	$ 1,667

Property and Equipment, Net - Summary of Property and Equipment Net (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Property, Plant and Equipment
Property plant and equipment, gross	$ 8,955	$ 8,920
Less: Accumulated depreciation and amortization	(7,243)	(7,005)
Property and equipment, net	1,712	1,915
Laboratory equipment
Property, Plant and Equipment
Property plant and equipment, gross	8,070	8,035
Furniture and fixtures
Property, Plant and Equipment
Property plant and equipment, gross	839	839
Computer equipment and software
Property, Plant and Equipment
Property plant and equipment, gross	$ 46	$ 46

Nature of Business, Going Concern and Basis of Presentation	3 Months Ended
	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business, Going Concern and Basis of Presentation	Nature of Business, Going Concern and Basis of Presentation Nature of Business Foghorn Therapeutics Inc. (the “Company”) is a clinical-stage biopharmaceutical company discovering and developing a new class of medicines targeting genetically determined dependencies within the chromatin regulatory system. The Company uses its proprietary Gene Traffic Control platform to identify, validate and potentially drug targets within the system. The Company was founded in October 2015 as a Delaware corporation. The Company is headquartered in Watertown, Massachusetts. The Company is subject to risks similar to those of other clinical-stage companies in the biopharmaceutical industry, including dependence on key individuals, the need to develop commercially viable products, competition from other companies, many of whom are larger and better capitalized, and the need to obtain adequate additional financing to fund the development of its products. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be maintained, that any products developed will obtain required regulatory approval or that any approved products will be commercially viable. Even if the Company’s development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from the sale of its products. Going concern The accompanying unaudited condensed consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets and the satisfaction of liabilities and commitments in the ordinary course of business. Since inception, the Company has funded its operations primarily with proceeds from sales of preferred stock, upfront and milestone payments from collaboration agreements, public offerings and a stock purchase agreement. The Company has incurred recurring losses, including net losses of $19.9 million and $18.8 million for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026, the Company had an accumulated deficit of $652.3 million. The Company expects to continue to generate operating losses in the foreseeable future. As of the issuance date of these interim unaudited condensed consolidated financial statements the Company expects that its cash, cash equivalents and marketable securities will be sufficient to fund its operating expenses and capital expenditure requirements for at least 12 months. The Company will need to obtain additional funding through public or private equity offerings, debt financings, collaborations, strategic alliances and/or licensing arrangements to continue to fund its operations. The Company may not be able to obtain financing on acceptable terms, or at all, and the Company may not be able to enter into collaborative or strategic alliances or licensing arrangements. The terms of any financing may adversely affect the holdings or the rights of the Company’s stockholders. Arrangements with collaborators or others may require the Company to relinquish rights to certain of its technologies or programs. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its research and development programs, pipeline expansion or commercialization efforts, which could adversely affect its business prospects. Although management will continue to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding in the future on terms acceptable to the Company to fund continuing operations when needed or at all. Basis of presentation The Company’s unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the United States Securities and Exchange Commission for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. All intercompany accounts and transactions have been eliminated in consolidation. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Income Statement [Abstract]
Collaboration revenue	$ 3,267	$ 5,952
Operating expenses:
Research and development	18,259	21,626
General and administrative	6,581	7,239
Total operating expenses	24,840	28,865
Loss from operations	(21,573)	(22,913)
Other income, net:
Interest income	1,742	2,692
Other income (expense), net	(44)	1,387
Total other income, net	1,698	4,079
Net loss	$ (19,875)	$ (18,834)
Net loss per share attributable to common stockholders—basic (in dollars per share)	$ (0.29)	$ (0.30)
Net loss per share attributable to common stockholders—diluted (in dollars per share)	$ (0.29)	$ (0.30)
Weighted average common shares outstanding—basic (in shares)	69,540,075	62,848,673
Weighted average common shares outstanding—diluted (in shares)	69,540,075	62,848,673
Comprehensive loss:
Net loss	$ (19,875)	$ (18,834)
Other comprehensive loss:
Unrealized losses on marketable securities	(157)	(121)
Total other comprehensive loss	(157)	(121)
Total comprehensive loss	$ (20,032)	$ (18,955)
Revenue from Contract with Customer, Product and Service Flag	Collaboration Revenue [Member]	Collaboration Revenue [Member]

Common Stock and Net Loss Per Share - Summary of Earnings Per Share Diluted Anti-Dilutive Impact (Details) - shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares excluded from the calculation of earnings per share (in shares)	21,305,679	10,804,075
Stock options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares excluded from the calculation of earnings per share (in shares)	13,835,670	10,785,630
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares excluded from the calculation of earnings per share (in shares)	7,470,009	18,445

Common Stock and Net Loss Per Share - Additional Information (Details)				3 Months Ended
	Jan. 09, 2026 USD ($) $ / shares shares	Mar. 20, 2025 USD ($)	Apr. 15, 2022 USD ($)	Mar. 31, 2026 vote $ / shares shares	Dec. 31, 2025 $ / shares
Antidilutive Securities Excluded from Computation of Earnings Per Share
Common stock, par value (in dollars per share) \| $ / shares				$ 0.0001	$ 0.0001
Voting rights per share \| vote				1
Warrants exercisable term				4 years 1 month 17 days
Weighted-average price per share (in dollars per share) \| $ / shares	$ 13.42
Adjusted exercise price per share (in dollars per share) \| $ / shares	$ 6.71
Exercise of warrants lower limit after exercise as percentage of common stock	9.99%
Maximum beneficial ownership limitation percentage	19.99%
Pre-funded warrants were exercised (in shares) \| shares				0
Pre-Funded Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share
Class of warrant or right, number of securities called by warrants or rights (in shares) \| shares	5,421,250
Exercise price of warrant (in dollars per share) \| $ / shares	$ 0.0001
Warrants exercisable term	20 years
Series 1 and Series 2 Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share
Class of warrant or right, number of securities called by warrants or rights (in shares) \| shares	7,451,564
Series 1 Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share
Exercise price of warrant (in dollars per share) \| $ / shares	$ 13.42
Number of warrants outstanding (shares) \| shares	3,725,782
Series 2 Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share
Exercise price of warrant (in dollars per share) \| $ / shares	$ 20.13
Number of warrants outstanding (shares) \| shares	3,725,782
Series Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share
Class of warrant or right, number of securities called by warrants or rights (in shares) \| shares	7,451,564
Fair value of warrants \| $	$ 12,200,000
Warrants and rights outstanding, measurement input				0.882
January 2026 Offering
Antidilutive Securities Excluded from Computation of Earnings Per Share
Sale of stock, number of shares issued in transaction (in shares) \| shares	2,030,314
Sale of stock issue price per share (in dollars per share) \| $ / shares	$ 6.7099
Proceed from issuance of stock \| $	$ 50,000,000.0
Equity issuance cost \| $	$ 300,000
At-The-Market Offering
Antidilutive Securities Excluded from Computation of Earnings Per Share
Aggregate offering price \| $		$ 100,000,000	$ 200,000,000.0
Commission fees payable, percentage			3.00%

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 87,663	$ 80,876
Marketable securities	95,968	78,018
Restricted cash	1,250	1,250
Prepaid expenses and other current assets	3,183	3,091
Total current assets	188,064	163,235
Property and equipment, net	1,712	1,915
Restricted cash	2,000	2,000
Other assets	3	4
Operating lease right-of-use assets	30,388	30,949
Total assets	222,167	198,103
Current liabilities:
Accounts payable	3,317	4,266
Accrued expenses and other current liabilities	6,924	11,357
Operating lease liabilities	1,863	923
Deferred revenue	52,300	43,192
Total current liabilities	64,404	59,738
Operating lease liabilities, net of current portion	40,131	40,347
Deferred revenue, net of current portion	193,587	205,962
Other liabilities	453	556
Total liabilities	298,575	306,603
Commitments and contingencies (Note 10)
Stockholders’ deficit:
Preferred stock, $0.0001 par value; 25,000,000 shares authorized at March 31, 2026 and December 31, 2025; no shares issued and outstanding at March 31, 2026 and December 31, 2025	0	0
Common stock, $0.0001 par value; 175,000,000 shares authorized at March 31, 2026 and December 31, 2025; 58,710,490 shares issued and outstanding at March 31, 2026 and 56,657,329 shares issued and outstanding at December 31, 2025	6	6
Additional paid-in capital	576,061	523,937
Accumulated other comprehensive gain (loss)	(133)	24
Accumulated deficit	(652,342)	(632,467)
Total stockholders’ deficit	(76,408)	(108,500)
Total liabilities and stockholders’ deficit	$ 222,167	$ 198,103

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Payables and Accruals [Abstract]
Accrued external research and development expenses	$ 4,316	$ 4,194
Accrued employee compensation and benefits	1,514	5,921
Accrued professional fees	657	842
Other	437	400
Total	$ 6,924	$ 11,357

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Cash flows from operating activities:
Net loss	$ (19,875)	$ (18,834)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	2,383	2,692
Depreciation and amortization expense	238	827
Noncash lease expense	561	1,449
Accretion of discount on marketable securities	(388)	(818)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(91)	1,069
Accounts payable	(990)	284
Accrued expenses and other liabilities	(4,458)	(2,407)
Operating lease liabilities	621	(2,279)
Deferred revenue	(3,267)	(5,951)
Net cash used in operating activities	(25,266)	(23,968)
Cash flows from investing activities:
Purchases of property and equipment	0	(28)
Purchases of marketable securities	(66,938)	(51,124)
Proceeds from maturities of marketable securities	49,219	80,553
Net cash provided by (used in) investing activities	(17,719)	29,401
Cash flows from financing activities:
Proceeds from offerings of common stock, pre-funded warrants, and series warrants net of underwriting discounts and commissions	49,999	0
Payments of public offering costs	(316)	0
Proceeds from issuance of common stock upon exercise of stock options and employee stock purchase plan	89	139
Net cash provided by financing activities	49,772	139
Net increase in cash, cash equivalents and restricted cash	6,787	5,572
Cash, cash equivalents and restricted cash at beginning of period	84,126	57,162
Cash, cash equivalents and restricted cash at end of period	90,913	62,734
Supplemental disclosure and noncash investing and financing information:
Cash paid for taxes	2	4
Purchases of property and equipment included in accounts payable and accrued expenses	35	0
Public offering costs in accounts payable and accrued expenses	31	0
Asset acquired in finance lease	0	1,208
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	87,663	61,026
Restricted cash	3,250	1,708
Total cash, cash equivalents and restricted cash shown in the statement of cash flows	$ 90,913	$ 62,734

Segment Reporting (Tables)

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Summary of Reconciled Expense of Consolidated Statement of Operations and Comprehensive Loss

Further, the following represents information about segment revenue, segment loss and significant segment expenses (in thousands):


	Three Months Ended March 31,
		2026		2025
Collaboration revenue		$	3,267	$	5,952
Less:
Research and development:
Personnel expenses		5,739		6,344
FHD-286		192		991
Lilly partnered programs		2,290		4,625
Proprietary programs		5,996		3,447
Research and development operating and administrative costs		1,261		1,667
General and administrative:
Personnel expenses		3,017		2,927
External expenses		1,996		2,072
Facilities and IT related expenses, net of sublease income		1,761		1,877
Other expenses(1)		2,632		3,528

Plus:
Interest income		1,742		2,692
Net loss		$	(19,875)	$	(18,834)

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2026
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Leases The Company’s commitments under its lease are described in Note 9. License agreements The Company has entered into various exclusive and non-exclusive license agreements for certain technologies. Under the terms of these license agreements, the Company could be required to reimburse the licensors for patent expenses and remit amounts in the low single-digit as sales-based royalties upon the occurrence of specific events as outlined in the corresponding license agreements. The Company is also required to make annual license maintenance fees of less than $0.1 million and pay up to $1.1 million in regulatory milestones on each licensed product upon the occurrence of specific events as outlined in one of the license agreements. None of our current product candidates utilizes technologies covered by these licenses. Indemnification agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, contract research organizations, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and its executive officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. The Company has not incurred any material costs as a result of such indemnifications and is not currently aware of any indemnification claims. Legal Proceedings From time to time, the Company may become involved in litigation or other legal proceedings. The Company is not currently a party to any material litigation or legal proceedings. Income Tax Matters During the three months ended March 31, 2026, the Company was notified that it is currently under IRS audit related to the tax year ended December 31, 2023. The Company is currently evaluating the scope and potential outcomes of the tax audit.

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 238	$ 827

- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References + Details

Accrued Expenses and Other Current Liabilities (Tables)

3 Months Ended

Mar. 31, 2026

Payables and Accruals [Abstract]

Summary of Accrued Expenses

Accrued expenses consisted of the following (in thousands):


	March 31, 2026		December 31, 2025
Accrued external research and development expenses	$	4,316	$	4,194
Accrued employee compensation and benefits	1,514		5,921

Accrued professional fees	657		842

Other	437		400
	$	6,924	$	11,357

Leases

3 Months Ended

Mar. 31, 2026

Leases [Abstract]

Leases

The Company leases laboratory and office space under a non-cancelable operating lease (the “Operating Lease”). There have been no material changes to the Company's Operating Lease during the three months ended March 31, 2026. For additional information, see Note 10, Leases, to the consolidated financial statements in the Company's Annual Report on Form 10-K for the year ended December 31, 2025.

The components of lease expense were as follows for the three months ended March 31, 2026 and 2025 (in thousands):


	Three Months Ended March 31,
		2026		2025
Operating lease cost		$	1,285	$	1,932
Variable lease cost		—		809
		$	1,285	$	2,741

Supplemental disclosure of cash flow information related to leases was as follows (in thousands):


	Three Months Ended March 31,
	2026		2025
Cash paid for amounts included in the measurement of operating lease liabilities	$	—	$	2,762
Asset acquired in finance lease	$	—	1,208

The weighted average remaining lease term and discount rate was as follows:


	March 31, 2026		December 31, 2025
Weighted-average remaining lease term—operating leases (in years)	9.4		9.7
Weighted-average discount rate—operating leases	7.24	%	7.24	%

Future annual minimum lease payments under the Office Lease as of March 31, 2026 were as follows (in thousands):


Remainder of 2026 (nine months)	$	979
2027	4,280
2028	5,713
2029	6,774
2030	6,977
Thereafter	36,088
Total future minimum lease payments	60,811
Less: imputed interest	(18,453)
Less: lease incentives	(364)
Total operating lease liabilities	$	41,994


Included in the consolidated balance sheets (in thousands):	March 31, 2026
Current operating lease liabilities	$	1,863
Operating lease liabilities, net of current portion	40,131
Total operating lease liabilities	$	41,994

Sublease agreements

Through December 2025, the Company had subleased portions of premises under a previous office lease in Cambridge, Massachusetts. For additional information, see Note 10, Leases, to the consolidated financial statements in the Company's Annual Report on Form 10-K for the year ended December 31, 2025.

For the three months ended March 31, 2025, the Company recorded other income of $1.4 million, related to its subleases. For the three months ended March 31, 2026, the Company recorded no other income related to subleases as the Company has no subleases as of March 31, 2026

Leases

The components of lease expense were as follows for the three months ended March 31, 2026 and 2025 (in thousands):


	Three Months Ended March 31,
		2026		2025
Operating lease cost		$	1,285	$	1,932
Variable lease cost		—		809
		$	1,285	$	2,741

Supplemental disclosure of cash flow information related to leases was as follows (in thousands):


	Three Months Ended March 31,
	2026		2025
Cash paid for amounts included in the measurement of operating lease liabilities	$	—	$	2,762
Asset acquired in finance lease	$	—	1,208

The weighted average remaining lease term and discount rate was as follows:


	March 31, 2026		December 31, 2025
Weighted-average remaining lease term—operating leases (in years)	9.4		9.7
Weighted-average discount rate—operating leases	7.24	%	7.24	%

Future annual minimum lease payments under the Office Lease as of March 31, 2026 were as follows (in thousands):


Remainder of 2026 (nine months)	$	979
2027	4,280
2028	5,713
2029	6,774
2030	6,977
Thereafter	36,088
Total future minimum lease payments	60,811
Less: imputed interest	(18,453)
Less: lease incentives	(364)
Total operating lease liabilities	$	41,994


Included in the consolidated balance sheets (in thousands):	March 31, 2026
Current operating lease liabilities	$	1,863
Operating lease liabilities, net of current portion	40,131
Total operating lease liabilities	$	41,994

Sublease agreements

Marketable Securities and Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2026

Fair Value Disclosures [Abstract]

Summary of Available for Sale Marketable Securities by Security Type

As of March 31, 2026, available for sale marketable securities by security type consisted of (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value


Commercial paper (due within one year)	57,314		—		(60)		57,254
Corporate notes and bonds (due within one year)	33,771		—		(61)		33,710

Corporate notes and bonds (due after one year through two years)	5,016		—		(12)		5,004
Total	$	96,101	$	—	$	(133)	$	95,968

As of December 31, 2025, available for sale marketable securities by security type consisted of (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value

U.S. government agencies (due within one year)	1,500		—		—		1,500
Commercial paper (due within one year)	35,286		4		(3)		35,287
Corporate notes and bonds (due within one year)	41,208		23		—		41,231

Total	$	77,994	$	27	$	(3)	$	78,018

Summary of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands):


	Fair Value Measurements at March 31, 2026 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	79,991	$	—	$	—	$	79,991

Commercial paper	—		7,467		—		7,467
Marketable securities:


Commercial paper	—		57,254		—		57,254
Corporate notes and bonds	—		38,714		—		38,714
Total	$	79,991	$	103,435	$	—	$	183,426
	Fair Value Measurements at December 31, 2025 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	56,357	$	—	$	—	$	56,357

Commercial paper	—		24,227		—		24,227
Marketable securities:

U.S. government agencies	—		1,500		—		1,500
Commercial paper	—		35,287		—		35,287
Corporate notes and bonds	—		41,231		—		41,231
Total	$	56,357	$	102,245	$	—	$	158,602

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Marketable Securities and Fair Value Measurements - Summary of Available for Sale Marketable Securities by Security Type (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Amortized Cost	$ 96,101	$ 77,994
Gross Unrealized Gains	0	27
Gross Unrealized Losses	(133)	(3)
Estimated Fair Value	95,968	78,018
U.S. government agencies (due within one year)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Amortized Cost		1,500
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		1,500
Commercial paper (due within one year)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Amortized Cost	57,314	35,286
Gross Unrealized Gains	0	4
Gross Unrealized Losses	(60)	(3)
Estimated Fair Value	57,254	35,287
Corporate notes and bonds (due within one year)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Amortized Cost	33,771	41,208
Gross Unrealized Gains	0	23
Gross Unrealized Losses	(61)	0
Estimated Fair Value	33,710	$ 41,231
Corporate notes and bonds (due after one year through two years)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Amortized Cost	5,016
Gross Unrealized Gains	0
Gross Unrealized Losses	(12)
Estimated Fair Value	$ 5,004

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-SubTopic 10
-Topic 825
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-10

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482736/825-10-45-1A

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-12

Reference 10: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 103
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-103

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 14: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481830/320-10-45-1

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

+ Details

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense

Stock-based compensation expense was classified in the condensed consolidated statements of operations and comprehensive loss as follows (in thousands):


	Three Months Ended March 31,
		2026		2025
Research and development expenses		$	993	$	1,150
General and administrative expenses		1,390		1,542
		$	2,383	$	2,692

Marketable Securities and Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	$ 95,968	$ 78,018
Total	183,426	158,602
U.S. government agencies \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:		1,500
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	57,254	35,287
Corporate notes and bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	38,714	41,231
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	79,991	56,357
Level 1 \| U.S. government agencies \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:		0
Level 1 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	0	0
Level 1 \| Corporate notes and bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	103,435	102,245
Level 2 \| U.S. government agencies \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:		1,500
Level 2 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	57,254	35,287
Level 2 \| Corporate notes and bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	38,714	41,231
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	0	0
Level 3 \| U.S. government agencies \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:		0
Level 3 \| Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	0	0
Level 3 \| Corporate notes and bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Marketable securities:	0	0
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash equivalents:	79,991	56,357
Money market funds \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash equivalents:	79,991	56,357
Money market funds \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash equivalents:	0	0
Money market funds \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash equivalents:	0	0
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash equivalents:	7,467	24,227
Commercial paper \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash equivalents:	0	0
Commercial paper \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash equivalents:	7,467	24,227
Commercial paper \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash equivalents:	$ 0	$ 0

Stock-Based Compensation - Additional Information (Details) $ in Millions			3 Months Ended
	Jan. 01, 2025 shares	Oct. 21, 2020 shares	Mar. 31, 2026 USD ($) period shares
Share-based Payment Arrangement
Unrecognized compensation costs related to unvested options and unvested restricted stock \| $			$ 24.8
Weighted average period of unrecognized compensation costs (years)			3 years
2020 Equity Incentive Plan
Share-based Payment Arrangement
Number of shares authorized (in shares)			2,200,000
Common stock shares available for grant (in shares)			2,162,136
Percentage of automatic annual increase in number of shares			4.00%
Number of additional shares authorized (in shares)	2,266,293
Vesting period (years)			4 years
Stock option expiry period (years)			10 years
2016 Stock Incentive Plan
Share-based Payment Arrangement
Number of shares authorized (in shares)			5,078,295
2020 Employee Stock Purchase Plan
Share-based Payment Arrangement
Number of shares authorized (in shares)		360,000
Common stock shares available for grant (in shares)			2,633,981
Percentage of automatic annual increase in number of shares		1.00%
Number of additional shares authorized (in shares)	566,573
Maximum aggregate number of shares added to plan (in shares)		3,220,520
Percentage of payroll deductions			15.00%
Discount of shares rate, percent			15.00%
Number of offering periods (period) \| period			2
Personnel related (including stock-based compensation) \| $			$ 0.0

Stock-Based Compensation

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

2020 Equity Incentive Plan

The Company’s 2020 Equity Incentive Plan (the “2020 Plan”) provides for the grant of incentive stock options, non-qualified options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards. The number of shares initially reserved for issuance under the 2020 Plan was (i) 2,200,000 shares (the “share pool”), plus (ii) the number of shares of common stock available for issuance under the Company’s 2016 Stock Incentive Plan (the “2016 Plan”) as of the effective date of the 2020 Plan, plus the number of shares of Common Stock underlying awards under the 2016 Plan that on or after the date of adoption expire or become unexercisable without delivery of shares, are forfeited to, or repurchased for cash, are settled in cash, or otherwise become available again for grant under the 2016 Plan, in each case, in accordance with its terms (up to an aggregate of 5,078,295 shares). As of March 31, 2026, 2,162,136 shares remained available for future grant under the 2020 Plan.

The share pool will automatically increase on January 1 of each year from 2021 to 2030 by the lesser of (i) four percent of the number of shares of our Common Stock outstanding as of the close of business on the immediately preceding December 31 and (ii) the number of shares determined by the board of directors on or prior to such date for such year. The number of shares reserved for issuance under the 2020 Plan was increased by 2,266,293 shares effective January 1, 2026.

The 2020 Plan is administered by the board of directors or, at the discretion of the board of directors, by a committee of the board of directors. The exercise prices, vesting and other restrictions are determined at the discretion of the board of directors, or its committee if so delegated. Stock options granted with service-based vesting conditions generally vest over four years and expire after ten years. The exercise price for stock options granted is not less than the fair value of Common Stock on the date of grant. The Company bases fair value of common stock on the quoted market price.

2020 Employee Stock Purchase Plan

On October 21, 2020, the Company’s board of directors adopted and its stockholders approved the 2020 Employee Stock Purchase Plan (the “ESPP”), which became effective on October 21, 2020. The aggregate number of shares of Common Stock available for purchase pursuant to the exercise of options under the ESPP is 360,000 shares, plus an automatic annual increase, as of January 1 of each year from 2021 to 2030, equal to the lesser of one percent of the number of shares of Common Stock outstanding as of the close of business on the immediately preceding December 31 and (ii) the number of shares determined by the board of directors on or prior to such date for such year (up to a maximum of 3,220,520 shares). The number of shares reserved for issuance under the ESPP was increased by 566,573 shares effective January 1, 2026. As of March 31, 2026, 2,633,981 shares remained available for future grant under the ESPP.

Eligible employees may authorize payroll deductions of up to 15% of their eligible compensation during an offering period. The purchase of shares is done at a 15% discount on the lesser of (i) the Fair Market Value of a share of Stock on the first day of the offering period and (ii) the Fair Market Value of a share of Stock on the last day of the offering period. The Company currently holds two offering periods, September 1 and March 1, respectively. The Company recognized a de minimis amount of expense related to the ESPP for the three months ended March 31, 2026 and 2025.

Stock-Based Compensation

Stock-based compensation expense was classified in the condensed consolidated statements of operations and comprehensive loss as follows (in thousands):


	Three Months Ended March 31,
		2026		2025
Research and development expenses		$	993	$	1,150
General and administrative expenses		1,390		1,542
		$	2,383	$	2,692

As of March 31, 2026, total unrecognized compensation cost related to unvested options was $24.8 million, which is expected to be recognized over a weighted average period of 3.0 years.