Foghorn Therapeutics : September 2021 Foghorn Investor Presentation

Targeting the Chromatin Regulatory System

Broadening the Impact of Precision Medicines for Oncology and Other Diseases

September 2021

Forward-Looking Statements

Disclaimer, Confidentiality, and Forward-Looking Statements

This presentation contains forward-looking statements. All statements other than statements of historical facts contained in this presentation are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as "may," "will," "should," "expect," "plan," "anticipate," "could," "intend," "target," "project," "contemplate," "believe," "estimate," "predict," "potential" or "continue" or the negative of these terms or other similar expressions, although not all forward-looking statements contain these words. Forward-looking statements include, but are not limited to, statements concerning: the initiation, timing, progress and results of our research and development programs and preclinical and clinical trials, our ability to advance product candidates that we may develop and successfully complete preclinical and clinical studies; our ability to leverage our initial programs to develop additional product candidates using our Gene Traffic Control Platform; the impact of the COVID-19 pandemic in our and our collaborators' business operations, including our research and development programs and preclinical studies; developments related to our competitors and our industry; our ability to expand the target populations of our programs and the availability of patients for clinical testing; our ability to obtain regulatory approval for FHD-286,FHD-609 and any future product candidates from the FDA and other regulatory authorities; our ability to identify and enter into future license agreements and collaborations; our ability to continue to rely on our CDMOs and CROs for our manufacturing and research needs; regulatory developments in the United States and foreign countries; our ability to attract and retain key scientific and management personnel; the scope of protection we are able to establish, maintain and enforce for intellectual property rights covering FHD-286 and FHD-609, our future products and our Gene Traffic Control Platform; and our use of proceeds from our initial public offering, estimates of our expenses, capital requirements and needs for additional financing. Any forward-looking statements represent the Company's views only as of today and should not be relied upon as representing its views as of any subsequent date. The Company explicitly disclaims any obligation to update any forward-looking statements. The Company's business is subject to substantial risks and uncertainties.

The Chromatin Regulatory System: The Next Wave of Cancer Therapies

	1990s	2000s	2010s	The Future
Cytotoxics	Targeted	Kinases	IO / Cell Therapy	Medicines targeting
	Antibodies			breakdowns in the
				chromatin regulatory
				system

Cancer is one of the leading causes of death worldwide

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Dysregulation of the Chromatin Regulatory System Has Been Implicated in up to 50% of All Cancers

Significant Market Opportunity

50%	2.5M	$400+
of All Cancers	People	billion
Based on exome sequencing,	Patients impacted by these	2030 global oncology
the chromatin regulatory	cancers	market opportunity
system is implicated in ~50%
of all cancers

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First Two Programs in the Clinic, Broad Pipeline Advancing

Precision Oncology / Breadth and Depth

Program / Target	Modality	Discovery	IND-enabling	Phase 1		Phase 2	Phase 3	Global Rights
FHD-286		AML				Early Clinical Data (Q4 2021)
(BRG1 / BRM)	Enzyme inhibitor
				Early Clinical Data (Q4 2021)
	Uveal melanoma
FHD-609 (BRD9)	Protein degrader					Early Clinical Data (H1 2022)
Synovial sarcoma
	I) Enzyme inhibitor
	BRG1 mutated cancers
Selective BRM			IND 2022
II) Protein degrader
	BRG1 mutated cancers
Selective ARID1B	Protein degrader
ARID1A mutated cancers
Synthetic Lethal	I) Enzyme inhibitors
Targets (multiple)	II) Protein degraders
Transcription	Transcription factor disruptors
Factors (multiple)
Partnered program	Transcription factor disruptor
(undisclosed)

Gene Traffic Control® Platform

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