Epizyme : Corporate Presentation, January 2022

Rewriting Treatments for People with Cancer

January 2022

Nasdaq: EPZM

FORWARD-LOOKING STATEMENTS

Any statements in this presentation about future expectations, plans and prospects for Epizyme, Inc. and other statements containing the words "anticipate," "believe," "estimate," "expect," "intend," "may," "plan," "predict," "project," "target," "potential," "will," "would," "could," "should," "continue," and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various

important factors, including: whether commercial sales of TAZVERIK for epithelioid sarcoma and follicular lymphoma in the approved

indications will be successful; whether the refinement of the company's commercial strategy and cost reductions will achieve the company's objectives; whether tazemetostat will receive marketing approval for epithelioid sarcoma or follicular lymphoma in other jurisdictions, full approval in the United States or approval in any other indication; uncertainties inherent in the initiation of future clinical studies and in the availability and timing of data from ongoing clinical studies; whether results from preclinical studies or earlier clinical studies of the company's product candidates will be predictive of the results of future trials, such as the ongoing confirmatory trials of TAZVERIK; whether interim results of clinical studies will be predictive of the final results of the studies; whether results from clinical studies will warrant meetings with regulatory authorities, submissions for regulatory approval or review by governmental authorities under the accelerated approval process; whether the company will receive regulatory approvals, including accelerated approval, to conduct trials or to market products; whether the company's collaborations and licensing agreements with third parties will be successful; uncertainties as to the impact of the COVID-19 pandemic on the company's business, results of operations and financial condition; whether the company's cash resources will be sufficient to fund the company's foreseeable and unforeseeable operating expenses and capital expenditure requirements; other matters that could affect the availability or commercial success of tazemetostat; and other factors discussed in the "Risk Factors" section of the company's most recent Form 10-K or Form 10-Q filed with the SEC and in the company's other filings from time to time with the SEC. In addition, the forward-looking statements included in this presentation represent the company's views as of the date hereof and should not be relied upon as representing the company's views as of any date subsequent to the date hereof. The company anticipates that subsequent events and developments will cause the company's views to change. However, while the company may elect to update these forward-looking statements at some point in the future, the company specifically disclaims any obligation to do so.

TAZVERIK® is a registered trademark of Epizyme, Inc.

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EPIZYME

A FULLY INTEGRATED

COMMERCIAL PHARMACEUTICAL

COMPANY

	LABEL EXPANSION
BILLION DOLLAR	TRIALS REMAIN
PLUS	ON TRACK
GLOBAL ONCOLOGY	ENCOURAGING INITIAL
MARKET OPPORTUNITY	SAFETY RUN-IN RESULTS

Full prescribing information is available at www.TAZVERIK.com

FIRST-IN-CLASS EZH2 INHIBITOR APPROVED FOR 2 INDICATIONS

JANUARY 2020	JUNE 2020
Accelerated approval	Accelerated approval
granted in epithelioid	granted in R/R follicular
sarcoma (ES)	lymphoma (FL)

PHASE 1A TRIAL OF
NOVEL SETD2
INHIBITOR,	HIGH-VALUE
EZM0414 OPEN	RESEARCH PIPELINE
PATIENTS ACTIVELY	ADVANCING
SCREENING FOR	TOWARD CLINIC
ENROLLMENT
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BROAD THERAPEUTIC POTENTIAL IN SOLID TUMORS AND HEME MALIGNANCIES

NOVEL MECHANISM OF ACTION,

ORAL ADMINISTRATION

ACTIVITY DEMONSTRATED IN MULTIPLE CANCERS

GENERALLY WELL-TOLERATED;

LOW DISCONTINUATION RATES

POTENTIAL FOR EXTENDED TREATMENT DURATION

COMBINATION OPPORTUNITIES WITH SOC AND NOVEL TREATMENTS

Not for promotional use

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Our Vision to Fuel Long-term Growth

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	MAXIMIZE COMMERCIAL EFFECTIVENESS		BUILD ON TAVZERIK'S
		PIPELINE-IN-A-DRUG POTENTIAL
3	4
	EXPAND PIPELINE & PORTFOLIO TO		COLLABORATE TO EXPAND
	OVERCOME UNDRUGGABLE TARGETS		PATIENT REACH & BUILD VALUE

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