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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our consolidated financial statements and the related notes to those statements included elsewhere in this Annual Report on Form 10-K. In addition to historical financial information, the following discussion and analysis contains forward-looking statements that involve risks, uncertainties and assumptions. Some of the numbers included herein have been rounded for the convenience of presentation. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of many factors, including those discussed under “Risk Factors” and elsewhere in this Annual Report on Form 10-K.

Overview

Foghorn is a clinical stage, precision therapeutics biotechnology company pioneering a new class of medicines that treat serious diseases by correcting abnormal gene expression through selectively targeting the chromatin regulatory system, an untapped opportunity for therapeutic intervention in oncology and with potential in a wide spectrum of other diseases including virology, autoimmune diseases and neurology.

The chromatin regulatory system orchestrates gene expression—the turning on and off of genes—which is fundamental to how all our cells function. The chromatin regulatory system is implicated in approximately 50 percent of all cancers, and understanding how this system works could lead to an entirely new class of precision medicines. To our knowledge, we are the only company with the ability to study and target the chromatin regulatory system at scale, in context, and in an integrated way.

Our proprietary Gene Traffic Control® platform provides an integrated and mechanistic understanding of how the various components of the chromatin regulatory system interact, allowing us to identify, validate and potentially drug targets within this system. We have developed unique capabilities that have yielded new insights and scalability in drugging this new, previously untapped and promising area.

At present, we are working on more than 10 programs with one clinical-stage drug candidate currently in Phase 1 development and one drug candidate anticipated to begin clinical development this year. We have discovered highly selective chemical matter for some of the most challenging targets in oncology including BRM, CBP, EP300 and ARID1B, as well as other undisclosed targets. We believe our current pipeline has the potential to help more than 500,000 cancer patients. We take a

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small molecule modality agnostic approach to drugging targets which includes protein degraders, allosteric enzymatic inhibitors, and transcription factor disruptors. We are a biology first company which means we focus first on the underlying genetics and biology of a disease relevant target and then leverage the most appropriate drugging approach to impact the disease biology.

We are currently conducting a Phase 1 dose escalation study of FHD-286, a selective, allosteric ATPase inhibitor of BRM and BRG1, in combination with either decitabine or cytarabine in relapsed and/or refractory acute myeloid leukemia (“AML”) patients. As part of our collaboration with Loxo Oncology at Eli Lilly and Company (“Lilly”), we anticipate that a Phase 1 dose escalation study will start later this year with FHD-909, a selective ATPase inhibitor of BRM.

During the third quarter of 2023, we transitioned the BRM Selective inhibitor program to Lilly which triggered the 50/50 cost share for the BRM programs. Costs related to the cost-share are included in research and development expenses on the consolidated statements of operations and comprehensive loss.

Since our inception, we have focused substantially all of our resources on building our Gene Traffic Control platform, organizing and staffing our company, business planning, raising capital, conducting discovery and research activities, protecting our trade secrets, filing patent applications, identifying potential product candidates, undertaking preclinical studies and clinical trial activities, establishing arrangements with third parties for the manufacture of initial quantities of our product candidates and component materials and initiating two strategic collaborations. We do not have any products approved for sale and have not generated any revenue from product sales.

On December 10, 2021, we entered into a collaboration agreement (the “Lilly Collaboration Agreement”) with Lilly, for which we received an upfront payment of $300.0 million in January 2022 (see Note 8 to our notes to consolidated financial statements included elsewhere in this Annual Report on Form 10-K). Concurrent with the Lilly Collaboration Agreement, we also entered into a stock purchase agreement (the “Lilly SPA”) and issued and sold Lilly 4,000,000 shares of our common stock at a price of $20.00 per share, resulting in net proceeds of $80.0 million, of which $42.2 million was allocated to equity upon the issuance of our common stock.

In the third quarter of 2022, we achieved a research milestone related to a Research Collaboration and Exclusive License Agreement (the “Merck Collaboration Agreement”) with Merck Sharp & Dohme Corp. (“Merck”) and received a $5.0 million milestone payment from Merck.

We have incurred significant operating losses since our inception. For the years ended December 31, 2023 and 2022, we reported net losses of $98.4 million and $108.9 million, respectively. As of December 31, 2023, we had an accumulated deficit of $471.6 million. We expect to continue to incur significant expenses and increasing operating losses for at least the next several years. Our ability to generate any product revenue or product revenue sufficient to achieve profitability will depend on the successful development and eventual commercialization of one or more product candidates we are developing and may develop.

We expect that our expenses and capital requirements will increase substantially in connection with our ongoing activities, particularly if and as we:

•advance FHD-286 and continue preclinical and clinical development of product candidates from our current portfolio, including those partnered with Lilly;

•identify and advance additional research programs and additional product candidates;

•initiate preclinical testing for any new product candidates we identify and develop;

•obtain, maintain, expand, enforce, defend and protect our trade secrets and intellectual property portfolio and provide reimbursement of third-party expenses related to our patent portfolio;

•hire additional research and development personnel;

•add operational, legal, compliance, financial and management information systems and personnel to support our research, product development and operations;

•expand the capabilities of our platform;

•acquire or in-license product candidates, intellectual property and technologies;

•operate as a public company;

•seek marketing approvals for any product candidates that successfully complete clinical trials; and

•ultimately establish a sales, marketing and distribution infrastructure to commercialize any products for which we may obtain marketing approval.

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We will not generate revenue from product sales unless and until we successfully commercialize one of our product candidates, after completing clinical development and obtaining regulatory approval. If we obtain regulatory approval for any of our product candidates, we expect to incur significant expenses related to developing our commercialization capability to support product sales, marketing, manufacturing and distribution. Further, we expect to incur additional costs associated with operating as a public company.

As a result, we will need substantial additional funding to support our continuing operations and pursue our growth strategy. Until we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of equity offerings, debt financings and collaborations or licensing arrangements and the Lilly Collaboration Agreement. We may be unable to raise additional funds or enter into such other agreements or arrangements when needed on favorable terms, or at all. If we fail to raise capital or enter into such agreements as, and when, needed, we may have to significantly delay, scale back our development or commercialization plans for one or more of our product candidates.

Because of the numerous risks and uncertainties associated with pharmaceutical product development, we are unable to accurately predict the timing or amount of increased expenses or when, or if, we will be able to achieve or maintain profitability. Even if we are able to generate product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations.

Components of Our Results of Operations

Collaboration Revenue

To date, we have not generated any revenue from product sales and do not expect to do so in the near future. If our development efforts for our product candidates are successful and result in regulatory approval or licenses with third parties, we may generate revenue in the future from product sales, milestone payments under our existing collaboration agreements or payments from other license agreements that we may enter into with third parties.

In December of 2021, we entered into a strategic collaboration with 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 aforementioned selective BRM oncology program and an additional undisclosed oncology target. In addition, the collaboration includes three additional discovery programs using Foghorn’s proprietary Gene Traffic Control platform. Under the terms of the collaboration, Foghorn received upfront consideration of $300.0 million in cash pursuant to the Lilly Collaboration Agreement, together with an equity investment by Lilly of $80.0 million in shares of Foghorn common stock pursuant to the Lilly SPA.

For the BRM selective program and the additional undisclosed target program, Foghorn will lead discovery and early research activities, while Lilly will lead development and commercialization activities with participation from Foghorn in operational activities and cost sharing. Foghorn and Lilly will share 50/50 in the U.S. economics, and Foghorn is eligible to receive royalties on ex-U.S. sales starting in the low double-digit range and escalating into the twenties based on revenue levels.

For the additional discovery programs, Foghorn will lead discovery and early research activities. Foghorn may receive up to a total of $1.3 billion in potential development and commercialization milestones. Additionally, Foghorn will have an option to participate in a percentage of the U.S. economics and is eligible to receive tiered royalties from the mid-single digit to low-double digit range on sales outside the U.S. that may be exercised after the successful completion of the dose-finding toxicity studies.

We cannot provide assurances as to the timing of future milestones, royalty payments and economics associated with the strategic collaboration with Lilly, if any.

In the third quarter of 2023, we transitioned the BRM Selective inhibitor program to Lilly, for which Lilly will lead and we will participate and share in 50% of the costs until registrational trials. Costs incurred will continue to be included in research and development expenses on the consolidated statements of operations and comprehensive loss.

We recognized total deferred revenue of $337.8 million related to the Lilly Collaboration Agreement and the Lilly SPA, which included the $300.0 million upfront payment under the Lilly Collaboration Agreement as well as $37.8 million allocated to deferred revenue from the gross proceeds of the Lilly SPA to be recognized over the performance period. For the years ended December 31, 2023 and 2022, we recognized $17.1 million and $17.4 million, respectively, of revenue under the Lilly Collaboration Agreement and, as of December 31, 2023, we had $302.7 million of deferred revenue related to the above mentioned upfront payment and revenue allocation remaining on our consolidated balance sheets. In September 2023 we re-evaluated our estimates related to the Lilly Collaboration Agreement. As a result of this re-evaluation, expected future costs increased over the course of the Lilly Collaboration Agreement, resulting in an adjustment that decreased revenue by $3.2 million for the year ended December 31, 2023.

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In July 2020, we entered into the Merck Collaboration Agreement, pursuant to which we agreed to apply our proprietary Gene Traffic Control platform to discover and develop novel therapeutics. Under the Merck Collaboration Agreement, we granted Merck exclusive global rights to develop and commercialize drugs that target dysregulation of a single transcription factor. Under the terms of the Merck Collaboration Agreement, we received a nonrefundable upfront payment of $15.0 million from Merck. In the third quarter of 2022, we achieved a research milestone related to the Merck Collaboration Agreement and received a $5.0 million milestone payment from Merck.

On August 9, 2023 we received notice from Merck that it was terminating the Merck Collaboration Agreement effective November 7, 2023. At the time of notice, no material obligations remained under the Merck Collaboration Agreement. As such, we recognized the remaining $16.1 million of deferred revenue, related to the original $15.0 million upfront payment and $5.0 million milestone payment received from Merck, as revenue, for year ended December 31, 2023.

For the years ended December 31, 2023 and 2022, we recognized $17.0 million and $1.8 million, respectively, of revenue under the Merck Collaboration Agreement. As of December 31, 2023, we had no deferred revenue related to the upfront payment and milestone achievement remaining on our consolidated balance sheets.

Operating Expenses

Our operating expenses are comprised of research and development expenses and general and administrative expenses.

Research and Development Expenses

Research and development expenses consist primarily of costs incurred to progress our proprietary and partnered pipeline, including our discovery efforts, which include:

•personnel-related costs, including salaries, benefits and stock-based compensation expense, for employees engaged in research and development functions;

•expenses incurred in connection with our research programs and preclinical and clinical development of our product candidates, including under agreements with third parties, such as consultants and contractors and CROs;

•the cost of manufacturing drug substance and drug product for use in our research and preclinical studies and clinical trials under agreements with third parties, such as consultants and contractors and CDMOs;

•laboratory supplies and research materials;

•facilities, depreciation and amortization and other expenses, which include direct and allocated expenses for rent and maintenance of facilities and insurance; and

•payments made under third-party licensing agreements.

We track our direct external research and development expenses on a program-by-program basis. These consist of costs that include fees, reimbursed materials, and other costs paid to consultants, contractors, CDMOs, and CROs in connection with our preclinical, clinical and manufacturing activities. We do not allocate employee costs, costs associated with our discovery efforts, laboratory supplies, and facilities expenses, including depreciation or other indirect costs, to specific product development programs because these costs are deployed across multiple programs and our platform and, as such, are not separately classified.

We expect that our research and development expenses may increase in the future as we advance our programs into clinical development and continue our discovery, research and preclinical activities in the near term and in the future. At this time, we cannot accurately estimate or know the nature, timing and costs of the efforts that will be necessary to complete the preclinical and clinical development of any product candidates we may develop. A change in the outcome of any number of variables with respect to product candidates we may develop could significantly change the costs and timing associated with the development of that product candidate. We may never succeed in obtaining regulatory approval for any product candidates we may develop.

General and Administrative Expenses

General and administrative expenses consist primarily of personnel-related costs, including salaries, benefits and stock-based compensation, for employees engaged in executive, legal, finance and accounting and other administrative functions. General and administrative expenses also include professional fees for legal, patent, consulting, investor and public relations, human resources, and accounting and audit services as well as direct and allocated facility-related costs.

We anticipate that our general and administrative expenses may increase in the future as we continue to support our continued research activities and development of our programs and platform. We also anticipate that we will continue to incur increased accounting, audit, legal, regulatory, compliance, director and officer insurance costs and investor and public relations expenses associated with operating as a public company.

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Other Income (Expense)

Interest Income

Interest income consists of interest earned on our invested cash balances.

Other Income, Net

Other income (expense), net consists of sublease income and miscellaneous expense unrelated to our core operations.

Provision for Income Taxes

Since our inception, we have not recorded any federal or state income tax benefits for the net losses we have incurred in any year or for our federal or state earned research and development tax credits, due to our uncertainty of realizing a benefit from those items. During the year ended December 31, 2023, we recorded a provision for income taxes related to the $300.0 million upfront payment from the Lilly Collaboration Agreement which will be recognized as taxable income in the current year, and the required capitalization of research and development costs pursuant to Internal Revenue Code Section 174. As of December 31, 2023, the Company had U.S. federal net operating loss carryforwards of $3.0 million which can be carried forward indefinitely but limited to offset 80% of annual taxable income. As of December 31, 2023, the Company also had U.S. federal and state research and development tax credit carryforwards of $3.7 million and $2.6 million, respectively, which may be available to offset future tax liabilities and expire at various dates beginning in 2041 and 2037, respectively.

Critical Accounting Estimates

Our consolidated financial statements are prepared in accordance with generally accepted accounting principles in the United States, (“GAAP”). The preparation of our consolidated financial statements and related disclosures requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenue, costs and expenses and the disclosure of contingent assets and liabilities in our consolidated financial statements. We base our estimates on historical experience, known trends and events and various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. We evaluate our estimates and assumptions on an ongoing basis. Our actual results may differ from these estimates under different assumptions or conditions.

While our significant accounting policies are described in more detail in Note 2 to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K, we believe that the following accounting policies are those most critical to the judgments and estimates used in the preparation of our consolidated financial statements.

Revenue Recognition

We received significant non-refundable upfront payments under our collaboration agreements with Merck and Lilly, from which we recognize revenue over time using the cost-to-cost method. Under the cost-to-cost method, the extent of progress towards completion is measured based on the ratio of actual costs incurred to the total estimated costs expected upon satisfying the identified single performance obligation. In estimating the total costs to satisfy our performance obligation, we are required to make significant estimates including an estimate of the expected time and expected internal and external costs to fulfill the performance obligation. In developing these estimates we consider historical experience, relevant entity-specific factors, known market trends and conditions, and a variety of other factors we believe are relevant to estimating the total cost to fulfill the performance obligation. We periodically evaluate estimates against the actual time and costs incurred as well as any anticipated changes to the timing or estimated costs. Any cumulative effect of revisions to the total estimated costs to complete our performance obligation will be recorded in the period in which the changes are identified, and amounts can be reasonably estimated. While such revisions will have no impact on our cash flows, 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.

Accrued Research and Development Expenses

As part of the process of preparing our consolidated financial statements, we are required to estimate certain accrued research and development expenses. This process involves estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs. We make estimates of our accrued expenses as of each balance sheet date in our consolidated financial statements based on facts and circumstances known to us at that time. We periodically confirm the accuracy of the estimates with the service providers and make adjustments if necessary. Examples of estimated accrued research and development expenses include those related to fees paid to:

•vendors in connection with discovery, preclinical and clinical development activities;

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•CROs in connection with preclinical studies and testing and clinical trials; and

•CDMOs in connection with the process development and scale up activities and the production and manufacturing of materials.

We base the expense recorded related to contract research and manufacturing on our estimates of the services received and efforts expended pursuant to quotes and contracts with multiple CROs and CDMOs that conduct services and produce and supply materials. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, we adjust the accrual accordingly. Although we do not expect our estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period. While the majority of our service providers invoice us in arrears for services performed, on a pre-determined schedule or when contractual milestones are met, some require advance payments. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the expense. We record these as prepaid expenses on our consolidated balance sheets.

Results of Operations

Comparison of the Years Ended December 31, 2023 and 2022

The following table summarizes our results of operations for the years ended December 31, 2023 and 2022:

Year Ended December 31, Change

(in thousands)

Operating expenses:

Other income (expense):

Provision for income taxes (4,226) — $ (4,226)

Collaboration Revenue

Under our collaboration agreements, revenue is recognized based on the work performed during the period. Collaboration revenue was $34.2 million for the year ended December 31, 2023, compared to $19.2 million for the year ended December 31, 2022. The increase in collaboration revenue is attributed to:

•an increase in Merck collaboration revenue recognition of $15.2 million, driven by the termination of the Merck Collaboration Agreement in 2023 and the subsequent recognition of the remaining deferred revenue; and

•a decrease in Lilly collaboration revenue recognition of $0.3 million due to a change in estimated total costs to satisfy the remaining performance obligation during 2023 offset by increased work performed on Lilly partnered targets.

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Research and Development Expenses

The following table summarizes our research and development expenses for the years ended December 31, 2023 and 2022:

Year Ended December 31, Change

(in thousands)

Research and development program expenses:

Platform, research and discovery, and unallocated expenses:

Personnel related (including stock-based compensation) 36,702 32,612 4,090

Research and development expenses were $109.7 million for the year ended December 31, 2023, compared to $105.6 million for the year ended December 31, 2022. The increase is attributed to the following:

•an increase in platform and other early stage research costs of $10.2 million, including an increase of $2.4 million related to the advancement of Lilly partnered targets, which was due to continued investment and development of our platform and early research pipeline;

•an increase in personnel-related costs of $4.1 million, including a $0.4 million increase in stock-based compensation expense, due to higher average headcount in our research and development functions compared to prior year, and $1.4 million in one-time separation costs; and

•an increase in facility-related and other expenses of $1.1 million due to the increased costs of supporting our research and development organization and their research efforts;

Partially offset by:

•a decrease in our FHD-286 program costs of $7.7 million, driven by a decline in development spend in 2023 as the Company’s Phase 1 study in AML/MDS was on clinical hold until June 2023 and the shutdown of the Phase 1 uveal melanoma study beginning in the second quarter of 2023; and

•a decrease in our FHD-609 program costs of $3.7 million associated with the partial clinical hold and subsequent shutdown of the Phase 1 clinical trial for FHD-609 in synovial sarcoma and SMARCAB1-loss tumors, which started in the second quarter of 2023.

General and Administrative Expenses

The following table summarizes our general and administrative expenses for the years ended December 31, 2023 and 2022:

Year Ended December 31,

(in thousands)

Personnel related (including stock-based compensation) $ 20,566 $ 18,243 $ 2,323

Facilities and IT related expenses and other 4,642 5,583 (941)

General and administrative expenses were $32.4 million for the year ended December 31, 2023, compared to $30.7 million for the year ended December 31, 2022. The increase is attributed to the following:

•an increase in personnel-related costs of $2.3 million, including a $1.4 million increase in stock-based compensation expense, due to higher average headcount in our general and administrative function to support our business; and

•a decrease in facility related and other expense of $0.9 million, which was primarily due to a decrease in insurance related expense and less overall purchases of non-capital equipment in 2023.

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Other Income (Expense)

Total other income, net was $13.7 million for the year ended December 31, 2023, compared to $8.3 million for the year ended December 31, 2022. The increase in total other income, net was primarily due to an increase in interest income driven by an increase in the average interest rate partially offset by lower average cash balances throughout the year ended December 31, 2023 compared to the year ended December 31, 2022.

Provision for income taxes

For the year ended December 31, 2023, we recorded an income tax provision of $4.2 million. The income tax provision is primarily driven by the current federal and state taxes related to the $300.0 million upfront payment for Lilly Collaboration Agreement, which will be recognized as taxable income in the current year, and the required capitalization of research and development costs pursuant to Internal Revenue Code Section 174. We did not record a provision for income taxes for the year ended December 31, 2022.

Liquidity and Capital Resources

Since our inception in October 2015, we have incurred significant operating losses. We expect to incur significant expenses and operating losses for the foreseeable future as we support our continued research activities and development of our programs and platform. Through December 31, 2023, we have funded our operations with proceeds from our initial public offering (“IPO”) in October 2020, sales of preferred stock, term loans, an upfront payment of $15.0 million we received in July 2020 under the Merck Collaboration Agreement, proceeds we received in December 2021 under the Lilly SPA of $80.0 million, an upfront payment of $300.0 million received in January 2022 under the Lilly Collaboration Agreement and a payment of $5.0 million received from Merck under the Merck Collaboration Agreement for the achievement of a research milestone. As of December 31, 2023, we had cash, cash equivalents and marketable securities of $234.1 million.

Cash Flows

The following table summarizes our sources and uses of cash for each of the periods presented:

Year Ended December 31,

(in thousands)

Net cash provided by (used in) operating activities $ (118,106) $ 193,612

Net cash provided by (used in) investing activities 144,450 (244,322)

Net cash provided by financing activities 1,778 1,763

Operating Activities

For the year ended December 31, 2023, operating activities used $118.1 million of cash, resulting from our net loss of $98.4 million to fund our operations and by changes in our operating assets and liabilities of $41.9 million partially offset by net non-cash charges of $22.2 million. Net cash provided by changes in our operating assets and liabilities for the year ended December 31, 2023 consisted primarily of a decrease of $34.2 million in deferred revenue resulting from the recognition of revenue on the upfront payments received in connection with our collaboration agreements, a $7.5 million decrease in operating lease liabilities and a $0.2 million net decrease in working capital.

For the year ended December 31, 2022, operating activities provided $193.6 million of cash, resulting from net cash provided by changes in our operating assets and liabilities of $281.5 million and by net non-cash charges of $20.9 million partially offset by a net loss of $108.9 million to fund our operations. Net cash provided by changes in our operating assets and liabilities for the year ended December 31, 2022 consisted primarily of a $302.7 million net increase in working capital. This was primarily driven by to the $300.0 million of cash received related to our collaboration receivable from Lilly and an increase of $4.3 million in deferred revenue related to the $5.0 million milestone payment from Merck, partially offset by a $18.5 million decrease in deferred revenue resulting from the recognition of revenue on the upfront and milestone payments received in connection with our collaboration agreements and a $7.0 million decrease in operating lease liabilities.

Investing Activities

For the year ended December 31, 2023, net cash provided by investing activities was $144.5 million primarily due to $219.6 million of marketable securities maturing, offset by $73.9 million of purchases of marketable securities and $1.2 million in purchases of property and equipment.

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For the year ended December 31, 2022, net cash used in investing activities was $244.3 million primarily due to $409.3 million of purchases of marketable securities and $1.2 million in purchases of property and equipment partially offset by $166.2 million of maturities of marketable securities.

Financing Activities

For the year ended December 31, 2023 and 2022, net cash provided by financing activities was $1.8 million, consisting of net proceeds from the exercise of common stock options and the employee stock purchase plan.

Funding Requirements

We expect our expenses to increase substantially in connection with our ongoing activities, particularly as we advance the preclinical activities, initiate clinical trials for our product candidates in development, including those partnered with Lilly, and continue to fund on-going clinical activities. As of the issuance date of the consolidated financial statements included elsewhere in this Annual Report on Form 10-K, we expect that our cash, cash equivalents and marketable securities will be sufficient to fund our operating expenses and capital expenditure requirements for at least twelve months. We have based this estimate on assumptions that may prove to be inaccurate. We could use our available capital resources sooner than we currently expect, in which case we would be required to obtain additional financing sooner than planned, which may not be available to us on acceptable terms, or at all. Our failure to raise capital as and when needed would have a negative impact on our financial condition and our ability to pursue our long-term business strategy. We will be required to obtain further funding through public or private equity offerings, debt financings, collaborations and licensing arrangements or other sources.

If we are unable to raise sufficient capital as and when needed, we may be required to significantly curtail, delay or discontinue one or more of our research or development programs or the commercialization of any product candidate we may develop, or be unable to expand our operations or otherwise capitalize on our business opportunities. If we raise additional funds through collaborations or licensing arrangements with third parties, we may have to relinquish valuable rights to future revenue streams or product candidates or grant licenses on terms that may not be favorable to us.

Off-balance Sheet Arrangements

We did not have during the periods presented, and we do not currently have, any off-balance sheet arrangements, as defined in the rules and regulations of the Securities and Exchange Commission.

Recently Issued Accounting Pronouncements

A description of recently issued accounting pronouncements that may potentially impact our financial position and results of operations is disclosed in Note 2 to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

We are a smaller reporting company, as defined in Rule 12b-2 under the Securities Exchange Act of 1934, as amended, for this reporting period and are not required to provide the information required under this item.

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Stockholders and the Board of Directors of Foghorn Therapeutics Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Foghorn Therapeutics Inc. and its subsidiary (the "Company"), as of December 31, 2023 and 2022, the related consolidated statements of operations and comprehensive loss, stockholders' equity (deficit), and cash flows for the years then ended, and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2023 and 2022, and the results of its operations and its cash flows for the years then ended, in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company's financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

/s/ Deloitte & Touche LLP

Boston, Massachusetts

March 7, 2024

We have served as the Company’s auditor since 2018.

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ITEM 8. CONSOLIDATED FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

FOGHORN THERAPEUTICS INC.

Index to Consolidated Financial Statements

Page

Report of Independent Registered Public Accounting Firm (PCAOB ID No. 34) 73

Consolidated Balance Sheets 75

Consolidated Statements of Operations and Comprehensive Loss 76

Consolidated Statements of Stockholders’ Equity (Deficit) 77

Consolidated Statements of Cash Flows 78

Notes to Consolidated Financial Statements 79

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Foghorn Therapeutics Inc.

Consolidated Balance Sheets

(In thousands, except share and per share amounts)

December 31,

Assets

Current assets:

Prepaid expenses and other current assets 6,124 5,601

Liabilities and Stockholders’ Equity (Deficit)

Current liabilities:

Accrued expenses and other current liabilities 9,108 11,001

Operating lease liabilities, net of current portion 36,555 45,537

Other liabilities — 29

Commitments and contingencies (Note 11)

Stockholders’ equity (deficit):

Accumulated other comprehensive loss (826) (3,986)

Total stockholders’ equity (deficit) (77,190) 112

Total liabilities and stockholders’ equity (deficit) $ 285,916 $ 404,883

The accompanying notes are an integral part of these consolidated financial statements.

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Foghorn Therapeutics Inc.

Consolidated Statements of Operations and Comprehensive Loss

(In thousands, except share and per share amounts)

Year Ended December 31,

Operating expenses:

Other income (expense):

Provision for income taxes (4,226) —

Comprehensive loss:

Other comprehensive loss:

Unrealized gains (losses) on marketable securities 3,160 (3,976)

Total other comprehensive gain (loss) 3,160 (3,976)

The accompanying notes are an integral part of these consolidated financial statements.

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Foghorn Therapeutics Inc.

Consolidated Statements of Stockholders’ Equity (Deficit)

(In thousands, except share amounts)

Shares Amount

Stock-based compensation expense — — 14,336 — — 14,336

Unrealized losses on marketable securities — — — (3,976) — (3,976)

Stock-based compensation expense — — 16,186 — — 16,186

Unrealized gains on marketable securities — — — 3,160 — 3,160

The accompanying notes are an integral part of these consolidated financial statements.

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Foghorn Therapeutics Inc.

Consolidated Statements of Cash Flows

(In thousands)

Year ended December 31,

Cash flows from operating activities:

Depreciation and amortization expense 3,451 3,321

Loss on disposal of property and equipment 3 6

Accretion of discount on marketable securities (2,651) (1,295)

Changes in operating assets and liabilities:

Prepaid expenses and other current assets 741 (307)

Collaboration receivable — 300,000

Accrued expenses and other liabilities (1,797) 1,441

Operating lease liabilities (7,514) (6,975)

Net cash provided by (used in) operating activities (118,106) 193,612

Cash flows from investing activities:

Purchases of property and equipment (1,224) (1,210)

Proceeds from maturities of marketable securities 219,575 166,233

Net cash provided by (used in) investing activities 144,450 (244,322)

Cash flows from financing activities:

Net cash provided by financing activities 1,778 1,763

Cash, cash equivalents and restricted cash at beginning of period 53,922 102,869

Cash, cash equivalents and restricted cash at end of period $ 82,044 $ 53,922

Supplemental cash flow information:

Cash paid for taxes $ 3,551 $ —

Supplemental disclosure of noncash investing and financing information:

Reconciliation of cash, cash equivalents and restricted cash:

Restricted cash (non-current) 1,708 1,708

The accompanying notes are an integral part of these consolidated financial statements.

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Foghorn Therapeutics Inc.

Notes to Consolidated Financial Statements

1. Nature of Business, Going Concern and Basis of Presentation

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 Cambridge, Massachusetts.

The Company is subject to risks similar to those of other early-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 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, an upfront payment from a collaboration agreement, a public offering and a stock purchase agreement all prior to 2022. In January 2022, the Company received an upfront payment of $300.0 million pursuant to a collaboration agreement (the “Lilly Collaboration Agreement”) completed with Loxo Oncology at Eli Lilly and Company (“Lilly”) (see Note 8). In the third quarter of 2022, the Company achieved a research milestone related to a collaboration agreement (the “Merck Collaboration Agreement”) with Merck Sharp & Dohme Corp. (“Merck”) and received a $5.0 million milestone payment. The Company has incurred recurring losses, including net losses of $98.4 million and $108.9 million for the years ended December 31, 2023 and 2022, respectively. As of December 31, 2023, the Company had an accumulated deficit of $471.6 million. The Company expects to continue to generate operating losses in the foreseeable future. As of the issuance date of these 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 consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The accompanying 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”).

2. Summary of Significant Accounting Policies

Use of estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Significant estimates and

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assumptions reflected in these consolidated financial statements include, but are not limited to, revenue recognition and the accrual of research and development expenses. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates as there are changes in circumstances, facts and experience. Actual results may differ from those estimates or assumptions.

Concentrations of credit risk and of significant suppliers

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, cash equivalents and marketable securities. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

The Company relies, and expects to continue to rely, on a small number of vendors to provide services, supplies and materials for certain activities related to its programs. These programs could be adversely affected by a significant interruption in these services or the availability of materials.

Cash equivalents

The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents.

Marketable Securities

The Company’s marketable securities are classified as available-for-sale and are carried at fair value with the unrealized gains and losses reported as a component of accumulated other comprehensive loss in stockholders’ equity. The Company classifies its marketable securities with maturities beyond one year as short-term, based on their highly liquid nature and because such marketable securities are available for current operations.

The Company reviews marketable securities whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying value is not recoverable. For available-for-sale debt securities, the credit allowance is limited to the amount that fair value is less than amortized cost. Unrealized gains (losses) are evaluated for impairment under ASC 326, Financial Instruments - Credit Losses, to determine if the impairment is credit-related or noncredit-related. Credit-related impairment is recognized as an allowance on the consolidated balance sheets with a corresponding adjustment to earnings, and noncredit-related impairment is recognized in other comprehensive loss. Evidence considered in this assessment includes reasons for the impairment, compliance with our investment policy, the severity of the impairment, collectability of the security, and any adverse conditions specifically related to the security, an industry, or geographic area.

Unrealized gains and losses are included as a component of accumulated other comprehensive loss in the consolidated balance sheets and consolidated statements of stockholders’ equity (deficit) and a component of total comprehensive loss. Realized gains and losses are included as a component of other income (expense), net based on the specific identification method.

Restricted cash

Amounts included in restricted cash represent amounts pledged as collateral for letters of credit required for security deposits on the Company’s leased facilities. These amounts are classified as restricted cash in the Company’s consolidated balance sheets.

Property and equipment

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expense is recognized using the straight-line method over the estimated useful life of each asset as follows:

Estimated Useful Life

Laboratory equipment 5 years

Furniture and fixtures 5 years

Computer equipment and software 3 years

Leasehold improvements Shorter of useful life or remaining term of lease

Costs for capital assets not yet placed into service are depreciated once placed into service. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation and amortization are removed from the accounts and any resulting gain or loss is included in loss from operations. Expenditures for repairs and maintenance are charged to expense as incurred.

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Impairment of long-lived assets

The Company evaluates its long-lived assets, which consist primarily of property and equipment and operating lease right-of-use assets, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the asset exceeds the fair value of the asset. The Company recorded no impairment losses on long-lived assets for the years ended December 31, 2023 or 2022.

Fair value measurements

Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

•Level 1—Quoted prices in active markets for identical assets or liabilities.

•Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

•Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

The Company’s cash equivalents and marketable securities are carried at fair value, determined according to the fair value hierarchy described above (see Note 3). The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities.

Collaboration Agreements

The Company analyzes its collaboration arrangements to assess whether they are within the scope of ASC 808, Collaborative Arrangements (“ASC 808”) to determine whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities. This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. When the Company has concluded that it has a customer relationship with one of its collaborators, the Company follows the guidance in ASC Topic 606, Revenue From Contracts With Customers (“ASC 606”).

Revenue recognition

The Company accounts for its collaboration arrangements under ASC 606, as the Company concluded that it has a customer relationship with each of its collaborators. For additional information on the Company’s collaboration agreements, see Note 8, Collaboration Agreements, to these consolidated financial statements. Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration to which it is entitled in exchange for the goods or services it transfers to the customer.

The Company assesses the goods or services promised within each contract and determines those that are performance obligations. The promised goods or services in the Company’s arrangements would likely consist of licenses, rights to the Company’s intellectual property, research and development services and related supporting activities. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and if so, they are considered performance obligations.

The Company assesses whether each promised good or service is distinct for the purpose of identifying the performance obligations in the contract. This assessment involves subjective determinations and requires management to make judgments about the individual promised goods or services and whether such are separable from the other aspects of the contractual

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relationship. Promised goods and services are considered distinct provided that: (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available to the customer (that is, the good or service is capable of being distinct) and (ii) the entity’s promise to transfer the good or service to the customer is separately identifiable from other promises in the contract (that is, the promise to transfer the good or service is distinct within the context of the contract). In assessing whether a promised good or service is distinct, the Company considers factors such as the research, development, manufacturing and commercialization capabilities of the customer and the availability of the associated expertise in the general marketplace. The Company also considers the intended benefit of the contract in assessing whether a promised good or service is separately identifiable from other promises in the contract. If a promised good or service is not distinct, an entity is required to combine that good or service with other promised goods or services until it identifies a bundle of goods or services that is distinct.

The transaction price is then determined and allocated to the identified performance obligations in proportion to their standalone selling prices (“SSP”) on a relative SSP basis. SSP is determined at contract inception and is not updated to reflect changes between contract inception and when the performance obligations are satisfied. Determining the SSP for performance obligations requires significant judgment. In developing the SSP for a performance obligation, the Company considers applicable market conditions and relevant entity-specific factors, including factors that were contemplated in negotiating the agreement with the customer and estimated costs. The Company validates the SSP for performance obligations by evaluating whether changes in the key assumptions used to determine the SSP will have a significant effect on the allocation of arrangement consideration between multiple performance obligations.

If the consideration promised in a contract includes a variable amount, the Company estimates the amount of consideration to which it will be entitled in exchange for transferring the promised goods or services to a customer. The Company determines the amount of variable consideration by using the expected value method or the most likely amount method. The Company includes the unconstrained amount of estimated variable consideration in the transaction price. The amount included in the transaction price is constrained to the amount for which it is probable that a significant reversal of cumulative revenue recognized will not occur. At the end of each subsequent reporting period, the Company re-evaluates the estimated variable consideration included in the transaction price and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis in the period of adjustment.

If an arrangement includes development and regulatory milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company’s control such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received.

For arrangements with licenses of intellectual property that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes royalty revenue and sales-based milestones at the later of (i) when the related sales occur, or (ii) when the performance obligation to which the royalty has been allocated has been satisfied.

The Company records amounts as accounts receivable when the right to consideration is deemed unconditional. When consideration is received, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a contract, a contract liability is recorded for deferred revenue.

In determining the transaction price, the Company adjusts consideration for the effects of the time value of money if the timing of payments provides the Company with a significant benefit of financing. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between the transfer of the promised goods or services to the customer and the payment by the customer will be one year or less. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) each performance obligation is satisfied, either at a point in time or over time, and if over time, recognition is based on the use of an output or input method.

Research and development costs

Research and development expenses consist of costs incurred in performing research and development activities, including salaries and bonuses, stock-based compensation, employee benefits, facilities costs, laboratory supplies, depreciation, and external costs of vendors engaged to conduct research, preclinical and clinical development activities as well as the cost of licensing technology.

Upfront payments and milestone payments made for the licensing of technology are expensed as research and development over the period to which they relate. Costs for research and development activities are expensed in the period in which they are incurred. Payments for such activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are reflected in the consolidated financial statements as prepaid expense or accrued research and

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development expense. Determining the prepaid and accrued balances at the end of any reporting period incorporate certain judgments and estimates by management that are based on information available to the Company including information provided by vendors regarding the progress to completion of specific tasks or costs incurred.

Patent costs

All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses.

Leases

The Company accounts for a contract as a lease when it has the right to control the asset for a period of time while obtaining substantially all of the asset’s economic benefits. The Company determines if an arrangement is a lease or contains an embedded lease at inception. For arrangements that meet the definition of a lease, the Company determines the initial classification and measurement of its right-of-use asset and lease liability at the lease commencement date and thereafter if modified. The lease term includes any renewal options that the Company is reasonably assured to exercise. The present value of lease payments is determined by using the interest rate implicit in the lease, if that rate is readily determinable; otherwise, the Company uses its estimated secured incremental borrowing rate for that lease term. The Company’s policy is to not record leases with an original term of twelve months or less on its consolidated balance sheets and recognizes those lease payments in the consolidated statements of operations and comprehensive loss as incurred over the lease term. The Company’s existing leases are for office and laboratory space and an equipment lease.

In addition to rent, the leases may require the Company to pay additional costs, such as utilities, maintenance and other operating costs, which are generally referred to as non-lease components. The Company has elected to not separate lease and non-lease components. Only the fixed costs for lease components and their associated non-lease components are accounted for as a single lease component and recognized as part of a right-of-use asset and liability. Rent expense for operating leases is recognized on a straight-line basis over the reasonably assured lease term based on the total lease payments and is included in operating expense in the consolidated statements of operations and comprehensive loss.

The Company receives payments and income from a sublease on a portion of the Company’s primary office lease (see Note 10). The Company recognizes sublease income on a straight-line basis over the lease term in other income (expense), net on the consolidated statements of operations and comprehensive loss, net of any revenue share due to the Company’s lessor.

Stock-based compensation

The Company measures stock options with service-based vesting or performance-based vesting granted to employees, non-employees and directors based on the fair value on the date of grant using the Black-Scholes option-pricing model. Compensation expense for the awards is recognized over the requisite service period for employees and directors and as services are delivered for non-employees, both of which are generally the vesting period of the respective award. The Company uses the straight-line method to record the expense of awards with only service-based vesting conditions. The Company uses the graded-vesting method to record the expense of awards with both service-based and performance-based vesting conditions, commencing once achievement of the performance condition becomes probable. The Company accounts for forfeitures of share-based awards as they occur.

The Company classifies stock-based compensation expense in its consolidated statements of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified.

Net loss per share

Basic net income (loss) per share attributable to common stockholders is computed by dividing net income (loss) attributable to common stockholders by the weighted average number of common shares outstanding for the period. Diluted net income (loss) per share attributable to common stockholders is computed by dividing net income (loss) attributable to common stockholders by the weighted average number of common shares outstanding for the period, adjusted for potential dilutive common shares.

In periods in which the Company reported a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.

The Company reported a net loss attributable to common stockholders for the years ended December 31, 2023 and 2022.

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

December 31,

Segments

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’s CODM is its chief executive officer and the Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company is focused on pioneering the discovery and development of a new class of medicines targeting genetically determined dependencies within the chromatin regulatory system.

Comprehensive loss

Comprehensive loss includes net loss as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. For the years ended December 31, 2023 and 2022, the Company’s only element of other comprehensive loss was unrealized gains (losses) on available for sale debt securities.

Income taxes

The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to the provision for income taxes. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies.

The Company accounts for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than-not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. Any resulting unrecognized tax benefits are recorded within the provision for income taxes.

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. The Company qualifies as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and has elected not to “opt out” of the extended transition related to complying with new or revised accounting standards, which means that when a standard is issued or revised and it has different application dates for public and nonpublic companies, the Company can adopt the new or revised standard at the time nonpublic companies adopt the new or revised standard and can do so until such time that the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company.

In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326). The new standard adjusts the accounting for assets held at amortized costs basis by eliminating the probable initial recognition threshold and requires an entity to reflect its current estimate of all expected credit losses as an allowance for credit losses. The Company adopted this as of January 1, 2023 and the adoption had no material impact to the Company’s consolidated financial position, results of operation, or cash flows.

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3. Marketable Securities and Fair Value Measurements

As of December 31, 2023, available for sale marketable securities by security type consisted of (in thousands):

AmortizedCost GrossUnrealizedGains GrossUnrealizedLosses EstimatedFairValue

U.S. government agencies (due within one year) $ 11,823 $ — $ (26) $ 11,797

Commercial paper (due within one year) 5,901 7 (2) 5,906

As of December 31, 2022, available for sale marketable securities by security type consisted of (in thousands):

AmortizedCost GrossUnrealizedGains GrossUnrealizedLosses EstimatedFairValue

U.S. treasury notes (due within one year) $ 7,987 $ — $ (115) $ 7,872

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 atDecember 31, 2023 Using:

Level 1 Level 2 Level 3 Total

Assets:

Cash equivalents:

Marketable securities:

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Fair Value Measurements atDecember 31, 2022 Using:

Level 1 Level 2 Level 3 Total

Assets:

Cash equivalents:

Marketable securities:

For the years ended December 31, 2023 and 2022, there were no transfers between Level 1, Level 2 and Level 3.

4. Property and Equipment, Net

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

December 31,

Computer equipment and software 115 100

Less: Accumulated depreciation and amortization (12,017) (8,611)

Depreciation and amortization expense was $3.5 million and $3.3 million for the years ended December 31, 2023 and 2022, respectively.

5. Accrued Expenses and Other Current Liabilities

Accrued expenses consisted of the following (in thousands):

December 31,

Accrued employee compensation and benefits $ 4,347 $ 4,743

Accrued external research and development expenses 3,610 5,262

Accrued income taxes 674 —

Accrued professional fees 441 678

6. Common Stock

Each share of 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.

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7. 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 December 31, 2023, 1,638,199 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 1,691,282 shares effective January 1, 2024.

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). As of December 31, 2023, 1,143,300 shares remained available for future grant under the ESPP. The number of shares reserved for issuance under the ESPP was increased by 422,820 shares effective January 1, 2024.

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 first offering period commenced under the ESPP on September 1, 2021. For the years ended December 31, 2023 and 2022, the Company recognized $0.1 million of expense related to the ESPP.

Stock option valuation

The fair value of stock option grants is estimated using the Black-Scholes option-pricing model. The Company currently lacks company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies. The expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.

The following table presents, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted for the years ended December 31, 2023 and 2022 which was as follows:

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Year Ended December 31,

Risk-free interest rate 3.7 % 2.1 %

Expected volatility 87.9 % 83.8 %

Expected dividend yield — —

Expected term (in years) 6.0 6.1

The following table summarizes the Company’s option activity for the year ended December 31, 2023 which was as follows:

(in years) (in thousands)

The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock. The aggregate intrinsic value of stock options exercised for the years ended December 31, 2023 and 2022 was $1.8 million and $4.3 million, respectively.

The weighted average grant-date fair value of stock options granted for the years ended December 31, 2023 and 2022 was $6.12 per share and $10.08 per share, respectively.

Stock-based compensation

The Company recorded stock-based compensation expense related to common stock options in the following expense categories of its consolidated statements of operations and comprehensive loss for the years ended December 31, 2023 and 2022 which was as follows (in thousands):

Year Ended December 31,

Research and development expenses $ 6,856 $ 6,452

General and administrative expenses 9,330 7,884

As of December 31, 2023, total unrecognized compensation cost related to unvested options was $26.2 million, which is expected to be recognized over a weighted average period of 2.2 years.

8. Collaboration Agreements

Lilly Collaboration Agreement and Stock Purchase Agreement

In December 2021, the Company entered into the Lilly Collaboration Agreement with 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 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

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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.

Under the terms of the Lilly Collaboration Agreement, Lilly agreed to make a nonrefundable upfront payment of $300.0 million to the Company within thirty (30) business days following the effective date of the agreement. Simultaneously with the execution of the Lilly Collaboration Agreement, the Company and Lilly entered into a stock purchase agreement with Lilly (the “Lilly SPA”), pursuant to which Lilly purchased 4,000,000 shares of the Company’s common stock at $20.00 per share, for an aggregate purchase price of $80.0 million.

The Company determined that the Lilly Collaboration Agreement and the Lilly SPA should be evaluated as a combined contract in accordance with ASC 606. The Company determined the fair value of the shares sold under the Lilly SPA to be $37.8 million less than the contractual purchase price stipulated in the Lilly SPA. In accordance with the applicable accounting guidance in ASC 815-40, Contracts in Entity’s Own Equity, the Company determined that the sale of stock should be recorded at fair value and therefore allocated the excess consideration received under the Lilly SPA to the Lilly Collaboration Agreement, which along with the non-refundable payment of $300.0 million will be recognized as revenue over the total estimated period of performance.

The Company accounted for the arrangement under ASC 606 as the Company concluded it has a customer relationship with Lilly. 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

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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 has transitioned the BRM Selective inhibitor program into development activities for which Lilly will lead and the Company will participate and share in 50% of the costs until registrational trials. Costs incurred will continue to be included in research and development expenses on the consolidated statements of operations and comprehensive loss.

The transaction price of $337.8 million was initially recorded as deferred revenue and is being recognized as revenue as the performance obligation is satisfied. The Company recognizes revenue using the cost-to-cost method, which it believes best depicts the transfer of control to the customer over time. Under the cost-to-cost method, the extent of progress towards completion is measured based on the ratio of actual costs incurred to the total estimated costs expected upon satisfying the identified performance obligation. Under this method, revenue is recorded as a percentage of the estimated transaction price based on the extent of progress towards completion. As of December 31, 2023, the potential research, development and regulatory milestone payments that the Company is eligible to receive were excluded from the transaction price as they were fully constrained by uncertain events. The Company will reevaluate the transaction price at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, and if necessary, the Company will adjust its estimate of the transaction price. Any additions to the transaction price would be reflected in the period as a cumulative revenue catch-up based on the ratio of costs incurred to the total estimated costs expected applied to the revised transaction price. Sales-based royalties and milestone payments, which predominantly relate to the license, will be recognized if and when the related sales occur.

As of December 31, 2023, the aggregate amount of the transaction price related to the unsatisfied portion of the performance obligation was $302.7 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 an estimate of the number of target substitutions Lilly may elect to make and the expected time and expected costs to fulfill the performance obligation. 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. While such revisions will have no impact on the Company’s cash flows, 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. During the year ended December 31, 2023, the Company re-evaluated its estimates related to the Lilly Collaboration Agreement. As a result of this re-evaluation, expected future costs over the course of the Lilly Collaboration Agreement increased, resulting in an adjustment that decreased revenue by $3.2 million for the year ended December 31, 2023.

At inception, the Company assessed the Lilly Collaboration Agreement to determine whether a significant financing component exists and concluded that a significant financing component does not exist. For the years ended December 31, 2023 and 2022, the Company had recorded $17.1 million and $17.4 million, respectively, of revenue under the Lilly Collaboration Agreement, which was included in deferred revenue at the beginning of the respective periods. As of December 31, 2023, the Company had a payable to Lilly of $1.5 million recorded in accrued expenses and other current liabilities on the Company’s consolidated balance sheets. As of December 31, 2022, the Company did not have a receivable or payable with Lilly.

Merck Collaboration Agreement

In July 2020, the Company entered into the Merck Collaboration Agreement with Merck, pursuant to which the Company and Merck applied Foghorn’s proprietary Gene Traffic Control platform to discover and develop novel therapeutics. Under the Merck Collaboration Agreement, the Company granted Merck exclusive global rights to develop, manufacture and commercialize drugs that target dysregulation of a single transcription factor.

The Company recognizes revenue using the cost-to-cost method. Under this method, revenue is recorded as a percentage of the estimated transaction price based on the extent of progress towards completion.

In the third quarter of 2022, the Company achieved a research milestone related to the Merck Collaboration Agreement and received a $5.0 million milestone payment from Merck.

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On August 9, 2023 the Company received notice from Merck that it is terminating the Merck Collaboration Agreement effective November 7, 2023. At the time of notice, no material obligations remained under the Merck Collaboration Agreement. As such, the Company recognized the remaining $16.1 million of deferred revenue, related to the original $15.0 million upfront payment and the $5.0 million milestone payment received from Merck, in the year ended December 31, 2023 as collaboration revenue.

As of December 31, 2023, there was no remaining performance obligation under the Merck Collaboration Agreement.

For the year ended December 31, 2023 and 2022, the Company had recorded $17.0 million and $1.8 million of revenue under the Merck Collaboration Agreement. For the years ended December 31, 2023 and 2022, the Company had recorded $17.0 million and $1.1 million, respectively, of revenue under the Merck Collaboration Agreement, which was included in deferred revenue at the beginning of the respective periods and the classification of deferred revenue between short-term and long-term.

9. Income Taxes

For the year ended December 31, 2023 the Company recorded a provision for income taxes of $4.2 million, representing an effective tax rate of 4.6%. The income tax provision and the effective tax rate is primarily driven by the current federal and state taxes related to the $300.0 million upfront payment for Lilly Collaboration Agreement, which will be recognized as taxable income in the current year, and the required capitalization of research and development costs pursuant to Internal Revenue Code Section 174. As a result, the Company expects to have taxable income in the current year, which will be reduced by utilizing available net operating loss carryforwards and research and development tax credit carryforwards.

The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets. Management has considered the Company’s history of cumulative net losses incurred since inception and its lack of commercialization of any products that would generate revenue from product sales and has concluded that it is more likely than not that the Company will not realize the benefits of the deferred tax assets. Accordingly, a full valuation allowance has been established against the net deferred tax assets.

For the year ended December 31, 2023, the Company recorded income tax expense on pre-tax losses of $94.2 million. Historically, no income tax benefits for the net deferred tax assets comprised primarily of net operating losses incurred and research and development tax credits generated in each year, due to its uncertainty of realizing a benefit from these items.

All of the Company’s operating losses since inception have been generated in the United States.

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate was as follows:

Year Ended December 31,

Federal statutory income tax rate (21.0) % (21.0) %

State taxes, net of federal benefit (6.3) (6.0)

Federal and state research and development tax credits (5.5) (4.3)

Change in deferred tax asset valuation allowance 33.0 30.0

Effective income tax rate 4.6 % 0.0 %

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Net deferred tax assets consisted of the following (in thousands):

December 31,

Deferred tax assets:

Net operating loss carryforwards $ 631 $ 59,398

Research and development tax credit carryforwards 5,777 14,071

Capitalized start-up costs 125 141

Deferred tax liabilities:

Operating lease right-of-use assets (8,197) (9,317)

Net deferred tax assets $ — $ —

As of December 31, 2023, the Company had U.S. federal net operating loss carryforwards of $3.0 million which can be carried forward indefinitely but limited to offset 80% of annual taxable income. As of December 31, 2023, the Company also had U.S. federal and state research and development tax credit carryforwards of $3.7 million and $2.6 million, respectively, which may be available to offset future tax liabilities and expire at various dates beginning in 2041 and 2037, respectively.

Beginning in 2022, the Tax Cuts and Jobs Act of 2017 eliminated the option to deduct research and development expenditures currently and requires taxpayers to amortize them, over five years for domestically incurred expenditures and over fifteen years for foreign incurred expenditures, pursuant to Internal Revenue Code Section 174. As of December 31, 2023, the Company has recorded a gross deferred tax asset of $170.6 million related to the Capitalized IRC Section 174 expenditures.

The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets. Management has considered the Company’s history of cumulative net losses incurred since inception and its lack of commercialization of any products that would generate revenue from product sales and has concluded that it is more likely than not that the Company will not realize the benefits of the deferred tax assets. Accordingly, a full valuation allowance has been established against the net deferred tax assets as of December 31, 2023 and 2022. Management reevaluates the positive and negative evidence at each reporting period.

The valuation allowance increased by $31.1 million and $32.8 million for the years ended December 31, 2023 and 2022, respectively, primarily as a result of the increase in total deferred tax assets.

As of December 31, 2023 and 2022, the Company had not recorded any amounts for unrecognized tax benefits. The Company files income tax returns in the U.S. Massachusetts, Florida and Tennessee as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by federal and state jurisdictions, where applicable. There are currently no pending tax examinations. Since the Company is in a loss carryforward position, it is generally subject to examination by the U.S. federal, state, and local income tax authorities for all tax years in which a loss carryforward is available.

10. Leases

In October 2019, the Company entered into a lease for 81,441 square feet of office and laboratory space in Cambridge, Massachusetts, commencing in January 2020 (the “Office Lease”). The initial term of the Office Lease was eight years with a five-year option to extend at fair-market rent at the time of the extension. In June 2020, the Company amended the Office Lease to defer payment of a portion of the base rent and operating expenses and to extend the lease term by nine months to September 2028. The base rent payments escalate annually over the eight-year lease term and totaled approximately $60.3 million. In connection with the Office Lease, the landlord agreed to fund up to $3.0 million in tenant improvements to the leased facility as well as up to an additional $16.3 million, which resulted in additional rent payments to the landlord over the lease term. For the years ended December 31, 2023 and 2022, $0.1 million and $0.1 million, respectively, of leasehold improvements were

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reimbursed by the landlord, which resulted in an increase to operating lease liabilities. The Company is obligated to pay its portion of real estate taxes and costs related to the premises, including costs of operations and management of the leased premises. The Company is required to maintain a cash balance of $1.7 million to secure a letter of credit associated with the lease. This amount was classified as restricted cash (non-current) on the consolidated balance sheets as of December 31, 2023 and 2022.

The components of lease expense were as follows for the years ended December 31, 2023 and 2022 (in thousands):

Year Ended December 31,

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

Year Ended December 31,

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

Weighted-average remaining lease term—operating leases (in years) 4.6 5.7

Weighted-average discount rate—operating leases 5.24 % 5.35 %

Future annual minimum lease payments under operating leases as of December 31, 2023 was as follows (in thousands):

Total future minimum lease payments 51,140

Less: imputed interest (6,067)

Total operating lease liabilities $ 45,073

Year Ended December 31,

Included in the consolidated balance sheets (in thousands): 2023 2022

Current operating lease liabilities $ 8,518 $ 5,970

Operating lease liabilities, net of current portion 36,555 45,537

Total operating lease liabilities $ 45,073 $ 51,507

Sublease agreement

During the year 2022, the Company was given notice by its sublessee (the “Former Sublessee”) that it would terminate the sublease in accordance with its terms and vacate the subleased premises, prior to the original expiration date. At the time, the Company was subletting 19,823 square feet of office space under the Office Lease, as amended, to the Former Sublessee.

On August 2, 2022, the Company entered into a sublease with another party (the “New Sublease”) to sublease the same premises. The New Sublease became effective during the fourth quarter of 2022 and has an initial term of 18 months. During the year ended December 31, 2023, the sublessee notified the Company that they will exercise the 12-month renewal option, extending the New Sublease through April 28, 2025. As of December 31, 2023, the remaining rent payments due to the Company under the New Sublease were $3.4 million. For the years ended December 31, 2023 and 2022, the Company recorded other income of $2.9 million and $2.6 million, respectively, related to its subleases.

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11. Commitments and Contingencies

Leases

The Company’s commitments under its leases are described in Note 10.

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 $0.3 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 utilize 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.

12. Defined Contribution Plan

The Company has a 401(k) defined contribution plan (the “401(k) Plan”) for its employees. Eligible employees may make pretax contributions to the 401(k) Plan up to statutory limits. For the year ended December 31, 2023, the Company recorded $0.4 million of expense related to 401(k) discretionary match. For the year ended December 31, 2022, there was no discretionary match made under the 401(k) Plan.

13. 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, 2024, and is subject to automatic one-year renewal terms until terminated. For the years ended December 31, 2023 and 2022, the Company paid the scientific founder $0.1 million. As of December 31, 2023 and 2022, the Company had less than $0.1 million in 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 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 years ended December 31, 2023 and 2022. For the years ended December 31, 2023 and 2022, the Company had recorded $17.1 million and $17.4 million, respectively, of revenue under the Lilly Collaboration Agreement. As of December 31, 2023 and 2022, the Company had $302.7 million and $319.8 million, of deferred revenue related to the Lilly Collaboration Agreement. As of December 31, 2023, the Company had a payable of $1.5 million due to Lilly. As of December 31, 2022, the Company did not have a receivable or payable with Lilly.

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

None.

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ITEM 9A. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

Our management, under the supervision and with the participation of our Principal Executive Officer (our Chief Executive Officer) and Principal Financial and Accounting Officer (our Chief Financial Officer), has evaluated the effectiveness of our disclosure controls and procedures as of period end. The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended, or the Exchange Act, means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure. Management recognizes that any disclosure controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives, and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Based on the evaluation of our disclosure controls and procedures as of December 31, 2023, our Principal Executive Officer and Principal Financial Officer concluded that, as of such date, our disclosure controls and procedures were effective at the reasonable assurance level.

Internal Control Over Financial Reporting

Management’s Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) to provide reasonable assurance regarding the reliability of our financial reporting and the preparation of consolidated financial statements for external purposes in accordance with U.S. generally accepted accounting principles (“GAAP”). Internal control over financial reporting is a process designed by, or under the supervision of, our Chief Executive Officer and Chief Financial Officer, and effected by our Board of Directors, management and other personnel, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles and includes those policies and procedures that:

•Pertain to the maintenance of records that accurately and fairly reflect in reasonable detail the transactions and dispositions of the assets of our company;

•Provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that our receipts and expenditures are being made only in accordance with authorizations of our management and directors; and

•Provide reasonable assurances regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material adverse effect on our financial statements.

Management assessed our internal control over financial reporting as of December 31, 2023, the end of our fiscal year. Management based its assessment on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework). Management’s assessment included evaluation of elements such as the design and operating effectiveness of key financial reporting controls, process documentation, accounting policies, and our overall control environment.

Based on this assessment, management has concluded that our internal controls over financial reporting were effective as of December 31, 2023 and provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external reporting purposes in accordance with GAAP. We reviewed the results of management’s assessment with the Audit Committee of our Board of Directors.

Internal control over financial reporting has inherent limitations. Internal control over financial reporting is a process that involves human diligence and compliance and is subject to lapses in judgment and breakdowns resulting from human failures. Internal control over financial reporting also can be circumvented by collusion or improper management override. Because of such limitations, there is a risk that material misstatements will not be prevented or detected on a timely basis by internal control over financial reporting. However, these inherent limitations are known features of the financial reporting process. Therefore, it is possible to design into the process safeguards to reduce, though not eliminate, this risk.

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Attestation Report of the Registered Public Accounting Firm

This Annual Report does not include an attestation report of our independent registered public accounting firm regarding internal control over financial reporting. Our report was not subject to attestation by our independent registered public accounting firm pursuant to the rules of the Securities and Exchange Commission for “emerging growth companies” that permit us to provide only management’s report in this report.

Changes in Internal Control Over Financial Reporting

No change in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) occurred during the three months ended December 31, 2023 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Inherent Limitations on Effectiveness of Internal Controls

In designing and evaluating the disclosure controls and procedures, management does not expect that our internal control over financial reporting will prevent or detect all errors and all fraud. A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control systems are met. Further, the design of a control system must reflect the fact that there are resource constraints, and the benefits of controls must be considered relative to their costs. The design of any disclosure controls and procedures also is based in part upon certain assumptions about the likelihood of future events, and there can be no assurance that any design will succeed in achieving its stated goals under all potential future conditions. Our management, including our Chief Executive Officer and Chief Financial Officer, believes that our disclosure controls and procedures and internal control over financial reporting are designed to provide reasonable assurance of achieving their objectives and are effective at the reasonable assurance level. However, our management does not expect that our disclosure controls and procedures or our internal control over financial reporting will prevent all errors and all fraud.

ITEM 9B. OTHER INFORMATION

None.

ITEM 9C. DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

Not applicable.

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PART III

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

OUR BOARD OF DIRECTORS

Below is a list of the names, ages as of February 29, 2024 and positions of the individuals who serve on our Board of Directors.

Name Age Position

Adrian Gottschalk 48 Chief Executive Officer and Director

Douglas G. Cole, M.D. 63 Chairman of the Board and Director

Scott Biller, Ph.D. 68 Director

Balkrishan (Simba) Gill, Ph.D. 59 Director

Adam M. Koppel, M.D., Ph.D. 54 Director

Thomas J. Lynch, Jr., M.D. 63 Director

Michael Mendelsohn, M.D. 68 Director

B. Lynne Parshall 69 Director

Ian F. Smith 58 Director

In accordance with our amended and restated certificate of incorporation, our Board of Directors is divided into three classes of directors. At each annual meeting of stockholders, a class of directors will be elected for a three-year term to succeed the class whose terms are then expiring, to serve from the time of election and qualification until the third annual meeting following their election or until their earlier death, resignation or removal. Our directors are divided among the three classes as follows:

The Class I directors are Scott Biller, Thomas J. Lynch and Michael Mendelsohn, and their terms will expire at our 2024 annual meeting of stockholders.

The Class II directors are Adrian Gottschalk, Adam M. Koppel and Ian F. Smith, and their terms will expire at our 2025 annual meeting of stockholders.

The Class III directors are Douglas G. Cole, Balkrishan (Simba) Gill and B. Lynne Parshall, and their terms will expire at our 2026 annual meeting of stockholders.

Our amended and restated certificate of incorporation provides that the authorized number of directors may be changed only by resolution of our Board of Directors. Any additional directorships resulting from an increase in the number of directors will be distributed among the three classes so that, as nearly as possible, each class will consist of one-third of the directors. The division of our Board of Directors into three classes with staggered three-year terms may delay or prevent a change of our management or a change in control.

DIRECTOR BIOGRAPHIES

Information concerning our directors is set forth below. The biographical description of each director includes the specific experience, qualifications, attributes and skills that led to the Board of Directors’ conclusion at the time of filing of this Annual Report that each person listed below should serve as a director.

DIRECTORS WITH TERMS EXPIRING IN 2024 (CLASS I DIRECTORS)

Scott Biller, Ph.D.,has served as a member of our Board of Directors since January 2020. Dr. Biller currently serves as a Senior Advisor for Agios Pharmaceuticals, where he previously served as the company’s Chief Scientific Officer from September 2010 to December 2019. Dr. Biller is also currently the sole proprietor of Biller Consulting, a consulting company serving the biopharmaceutical industry, and since December 2021 he has served as an Executive Venture Partner at the venture capital fund GV. From 2003 to 2010, Dr. Biller was Vice President and Head of Global Discovery Chemistry at the Novartis Institutes for Biomedical Research. Prior to that, Dr. Biller held the positions of Vice President, Pharmaceutical Candidate Optimization at the Bristol Myers Squibb, or BMS, Pharmaceutical Research Institute and Executive Director of Drug Discovery chemistry for the BMS research site in Lawrenceville, New Jersey. Since June 2020, Dr. Biller has served on the Board of Directors of Remix Therapeutics and, since February 2021, has served on the Board of Directors of Rome Therapeutics. Dr. Biller earned a S.B. degree from the Massachusetts Institute of Technology, a Ph.D. from Caltech and was an NIH Postdoctoral Fellow at Columbia University in natural product synthesis. We believe Dr. Biller is qualified to serve on our Board of Directors because of his extensive experience in drug discovery and development and his significant leadership experience in the biotechnology industry.

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Thomas J. Lynch, Jr., M.D., has served as a member of our Board of Directors since October 2022. Dr. Lynch is a world-renowned scientist, highly respected oncologist and successful leader of National Cancer Institute-Designated Comprehensive Cancer Centers. Since February 2020, Dr. Lynch has served as president and director of Fred Hutchinson Cancer Research Center, where he sets the strategic direction of the center, oversees center-wide initiatives and represents the Hutch’s interests to major partners and governmental bodies. He also directs the Fred Hutch/University of Washington Cancer Consortium and is principal investigator of its Cancer Center Support Grant. Before taking over as the Hutch’s sixth president, Dr. Lynch was most recently chief scientific officer of Bristol-Myers Squibb from March 2017 to October 2019. Prior to that he held leadership roles as CEO of Massachusetts General Physicians Organization from September 2015 to March 2017, director of Yale Cancer Center and physician-in-chief at Yale’s Smilow Cancer Hospital from April 2009 through March 2015. Prior to those positions, Dr. Lynch was chief of hematology-oncology at Massachusetts General Hospital and professor of medicine at Harvard Medical School. Dr. Lynch is a member of the American Association for Cancer Research, the American Society of Clinical Oncology, and the International Association for the Study of Lung Cancer. Earlier in his career he was part of the first research team to discover how targeted therapies could dramatically change outcomes for lung cancer patients with mutations in the EGFR, or epidermal growth factor receptor, gene. We believe Dr. Lynch is qualified to serve on our Board of Directors because of his extensive experience as a clinician and scientist, as well as his leadership experience in the oncology space.

Michael Mendelsohn, M.D.,has served as a member of our Board of Directors since April 2017. Dr. Mendelsohn is also the Founder and Board Chairman, as well as Chief Strategy Officer, of Cardurion Pharmaceuticals, where he has served since May 2016. He is also a Professor of Medicine and Cardiology at Tufts Medical Center and Tufts University School of Medicine. Since April 2015, Dr. Mendelsohn has served as a senior advisor and consultant to the Head of Research and Development at Takeda Pharmaceutical Co. Ltd. From December 2014 to December 2018, was Senior Advisor, Consultant and a member of the Pharmaceuticals Advisory Committee at Ironwood Pharmaceuticals for the chief scientific officer and president of R&D. From May 2014 to July 2017, Dr. Mendelsohn was a venture partner for SV Health Investors. From June 2010 to November 2013, Dr. Mendelsohn served as Senior Vice President and Global Head of Cardiovascular Research at Merck Research Laboratories. From 1993 to 2010, Dr. Mendelsohn was a Professor of Medicine and Cardiology at Tufts Medical Center and Tufts University School of Medicine, where he founded and was the executive director of the Molecular Cardiology Research Institute from 1997 to 2010. From 2008 to 2010, he also served as Chief Scientific Officer at Tufts. From 1987 to 1993, Dr. Mendelsohn was a member of the faculty of the Cardiovascular Division at Brigham and Women’s Hospital and Harvard Medical School. Dr. Mendelsohn received a B.A. in Chemistry and English from Amherst College and an M.D. from Harvard Medical School. We believe Dr. Mendelsohn is qualified to serve on our Board of Directors because of his extensive experience as a clinician and scientist, along with experience and insights as an active advisor and consultant to leadership in research and development for multinational biopharmaceutical companies.

DIRECTORS WITH TERMS EXPIRING IN 2025 (CLASS II DIRECTORS)

Adrian Gottschalk has served as our President, Chief Executive Officer and as a member of our Board of Directors since May 2017. Prior to joining Foghorn and since 2004, Mr. Gottschalk worked at Biogen Inc. where he was most recently a Senior Vice President and Neurodegeneration Therapeutic Area Head from November 2015 to May 2017. In this role, he was responsible for the late-stage development and commercialization of medicines for Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis, or ALS. Mr. Gottschalk holds a B.S. from Texas A&M University, an MBA from the Sloan School of Management at the Massachusetts Institute of Technology and an M.S. from the joint Harvard Medical School / Massachusetts Institute of Technology Division of Health Sciences & Technology (HST) Biomedical Enterprise Program. We believe that Mr. Gottschalk’s experience as our President and Chief Executive Officer along with 20 years of experience in the biotechnology field provides him with the qualifications and skills necessary to serve as a member of our Board of Directors.

Adam M. Koppel, M.D., Ph.D.,has served as a member of Foghorn’s board of directors since July 2017. Dr. Koppel currently serves as a partner of Bain Capital Life Sciences, a position he has held since June 2016. He initially joined Bain Capital Public Equity in 2003, where he was a leader within the healthcare sector until 2014. From 2014 to 2016, Dr. Koppel was executive vice president of corporate development and chief strategy officer at Biogen, Inc. Prior to joining Bain Capital Public Equity in 2003, Dr. Koppel was an associate principal at McKinsey & Co. in New Jersey where he served a variety of healthcare companies. Dr. Koppel sits on the board of directors of Solid Biosciences, Inc. and Cerevel Therapeutics Holdings, Inc. He also serves on the board of directors of Areteia Therapeutics, Inc. and Cardurion Pharmaceuticals, Inc., both private companies. Dr. Koppel previously served on the board of directors of BCLS Acquisition Corp., Trevena, Inc., Aptinyx Inc. and Dicerna Pharmaceuticals, Inc. Dr. Koppel graduated magna cum laude from Harvard University with an A.B. and A.M. in history and science. He received an M.D. and Ph.D. in neuroscience from the University of Pennsylvania School of Medicine and an M.B.A. from The Wharton School at the University of Pennsylvania, where he was a Palmer Scholar. We believe Dr. Koppel is qualified to serve on our Board of Directors due to his background as an executive officer, director and venture capital investor in biopharmaceutical companies, as well as his scientific and medical background.

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Ian F. Smith has served as a member of our Board of Directors since April 2021. Mr. Smith currently serves as a Senior Advisor to Bain Capital Life Sciences, which position he has held since January 2021. He has also served as Executive Chair of the board of directors of Solid Biosciences since April 2020, Chairman of the board of directors of iVexSol Inc. since August 2023, the Chairman of the board of directors of Rivus Pharmaceuticals since November 2023, and as a board member of Alkeus Pharmaceuticals and Stoke Therapeutics since December 2022 and September 2023, respectively. Mr. Smith also provides advisory and consulting services to these companies and other biotechnology companies. Prior to his current roles, Mr. Smith was Executive Vice President and Chief Operating Officer of Vertex Pharmaceuticals from September 2017 to January 2019 and prior to that served as Chief Financial Officer from October 2001 to September 2017. Prior to 2001, Mr. Smith was a partner in the Life Science and Technology Practice of the accounting firm Ernst & Young LLP. Mr. Smith received a B.A. with honors in accounting and finance from Manchester Metropolitan (UK). We believe Mr. Smith is qualified to serve on our Board of Directors due to his knowledge and experience across multiple roles in the biotechnology industry.

DIRECTORS WITH TERMS EXPIRING IN 2026 (CLASS III DIRECTORS)

Douglas Cole, M.D.,has served as a member of our Board of Directors since October 2015. Dr. Cole joined Flagship Pioneering, which conceives, creates, resources and develops first-in-category bioplatform companies, in 2001, and is currently a Managing Partner focused on life science investments. Dr. Cole currently serves on the board of directors of Sana Biomedicine and a number of private companies. In the past five years, Dr. Cole served on the boards of directors of Denali Therapeutics, Sigilon Therapeutics, Quanterix Corporation and Editas Medicine. Dr. Cole received his M.D. from the University of Pennsylvania School of Medicine and his B.A. in English from Dartmouth College. We believe Dr. Cole is qualified to sit on our Board of Directors given his substantial experience as an investor in emerging biopharmaceutical and life sciences companies as well as his experience serving on the boards of directors of multiple public and private biopharmaceutical companies.

Balkrishan (Simba) Gill, Ph.D.,has served as a member of our Board of Directors since July 2017. Dr. Gill was the CEO of Evelo Biosciences from 2015 to 2023. During the same period Dr. Gill was a special advisor and senior partner at Flagship Pioneering, an innovation enterprise that conceives, creates, resources and develops first-in-category life sciences companies. From 2016 to 2019, Dr. Gill served on the board of directors of Realm Therapeutics PLC. Dr. Gill received his Ph.D. from King’s College, London and his MBA from INSEAD. We believe Dr. Gill is qualified to serve on our Board of Directors due to his knowledge and experience in the venture capital and pharmaceutical industries.

B. Lynne Parshall has served as a member of our Board of Directors since August 2022. She has also served as a Director of Ionis Pharmaceuticals, Inc. since September 2000 and as a Senior Strategic Advisor to Ionis from January 2018 to December 2022. Previously she served as Ionis’s Chief Operating Officer from December 2007 through January 2018 and as its Chief Financial Officer from June 1994 through December 2012. She also served as its Corporate Secretary through 2014 and has served with Ionis in various executive roles since November 1991. Prior to joining Ionis, Ms. Parshall practiced law at Cooley LLP, where she was a partner from 1986 to 1991. Ms. Parshall has also served as the CEO of Lyme Pinnacle Consulting LLC, a strategic consulting firm in the life sciences industry, since 2018. Ms. Parshall has served on the boards of directors of Cytokinetics, Inc., a public biopharmaceutical company, since February 2013; Repertoire Immune Medicines, Inc., a private company in the life sciences industry, since 2021; Ring Therapeutics, Inc., a private company in the life sciences industry, since 2022; Alltrna, Inc., a private company in the life sciences industry since 2023; and Celdara Medical, LLC, a private company in the life sciences industry, since 2023. She also served on the board of directors of Akcea Therapeutics, Inc., a public biopharmaceutical company, from January 2015 until its acquisition by Ionis in October 2020. Ms. Parshall received her NACD Directorship Certification in 2023. Ms. Parshall received an A.B. from Harvard University and her J.D. from Stanford University. We believe Ms. Parshall is qualified to serve on our Board of Directors due to her knowledge and experience in the life sciences industry as well as her experience serving as a director on other public and private company boards.

Board Membership Criteria

Our Nominating and Corporate Governance Committee is responsible for developing and recommending to our Board of Directors criteria for Board membership and, consistent with those criteria, recommending to the Board of Directors director candidates and nominees for the next annual meeting of stockholders. As reflected in our Corporate Governance Guidelines, it is the policy of the Board of Directors that all directors should possess the highest personal and professional ethics, integrity and values, and be committed to representing the long-term interests of the Company’s stockholders. The Board of Directors believes that each director should possess the requisite ability, judgment and experience to oversee the Company’s business, and should contribute to the overall diversity of the Board of Directors. The Board of Directors considers the qualifications of directors and director candidates individually and in the broader context of its overall composition and the Company’s current and anticipated future needs. Stockholders may also nominate persons to be elected as directors in accordance with our bylaws and applicable law. The Nominating and Corporate Governance Committee does not have a written policy regarding

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stockholder nominations, but it has determined that it is the practice of the committee to consider candidates proposed by stockholders if made in accordance with our bylaws.

Board Meetings and Attendance

The Board of Directors held seven meetings during the year ended December 31, 2023. Each of the directors attended at least seventy-five percent (75%) of the meetings of the Board of Directors and the committees of the Board of Directors on which he or she served during the year ended December 31, 2023 (in each case, which were held during the period for which he or she was a director and/or a member of the applicable committee and excluding any meetings in which a director was an interested party).

The non-employee directors met in executive session during each of the regularly scheduled Board of Directors meetings during the year ended December 31, 2023.

Director Attendance at Annual Meeting of Stockholders

One director attended our 2023 annual meeting, which was held as a virtual-only meeting.

Role of the Board in Risk Oversight

Our Board of Directors has an active role, as a whole and also at the committee level, in overseeing the management of our risks. Our Board of Directors is responsible for general oversight of risks and regular review of information regarding our risks, including liquidity risks and operational risks. The compensation committee is responsible for overseeing the management of risks relating to our executive compensation plans and arrangements. The audit committee is responsible for overseeing the management of risks relating to accounting matters and financial reporting. The nominating and governance committee is responsible for overseeing the management of risks associated with the independence of our Board of Directors and potential conflicts of interest. Although each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire Board of Directors is regularly informed through discussions from committee members about such risks. Our Board of Directors believes its administration of its risk oversight function has not negatively affected our Board of Directors’ leadership structure.

BOARD COMMITTEES

Our Board of Directors has established an audit committee, a compensation committee and a nominating and corporate governance committee, each of which operates pursuant to a charter adopted by our Board of Directors. The Board of Directors may also establish other committees from time to time to assist us and the Board of Directors in their duties. The composition and functioning of all of our committees comply with all applicable requirements of the Sarbanes-Oxley Act, the Nasdaq Stock Market and the Exchange Act. Each committee’s charter is available on the corporate governance section of our website at https://foghorntx.com. Information contained on our website is not incorporated by reference into this Annual Report on Form 10-K, and you should not consider information contained on our website to be part of this prospectus or in deciding whether to purchase shares of our common stock.

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