Epizyme Announces Closing of Public Offering of Common Stock

CAMBRIDGE, Mass., Sept. 19, 2017 -- Epizyme, Inc. (NASDAQ:EPZM), a clinical-stage biopharmaceutical company creating novel epigenetic therapies, today announced the closing of its public offering of 10,557,000 shares of its common stock at a price of $15.25 per share, before underwriting discounts. The shares of common stock issued and sold in the offering at the closing include 1,377,000 shares issued upon the exercise in full by the underwriters of their option to purchase additional shares at the public offering price less the underwriting discount.

The aggregate net proceeds before expenses to Epizyme from the offering are approximately $151.3 million, after deducting underwriting discounts and commissions.

Epizyme anticipates using the net proceeds from this offering, together with its existing cash, cash equivalents and marketable securities to fund global development costs of tazemetostat outside of Japan, including the costs of its ongoing and planned clinical trials of and regulatory activities related to tazemetostat; to initiate supply chain and market development activities and prepare for the commercial launch of tazemetostat, if approved; to fund research and development costs to identify and develop other product candidates; and for working capital and other general corporate purposes. Based on its current operating plan, Epizyme expects that the net proceeds from the offering, together with its existing cash, cash equivalents and marketable securities, will enable it to fund its operating expenses and capital expenditure requirements at least into the third quarter of 2019.

Morgan Stanley, Jefferies and Leerink Partners acted as joint book-running managers for the proposed offering.

A shelf registration statement relating to the shares of common stock offered in the public offering was filed with the Securities and Exchange Commission (SEC) on April 15, 2016, and declared effective by the SEC on April 29, 2016. The offering was made only by means of a written prospectus and prospectus supplement that form a part of the registration statement. A prospectus supplement related to the offering has been filed with the SEC and may be obtained for free by visiting EDGAR on the SEC website at www.sec.gov. Copies of the final prospectus supplement and the accompanying prospectus relating to the securities being offered may also be obtained by contacting one of the following: Morgan Stanley & Co. LLC, Attention: Prospectus Department, 180 Varick Street, 2nd Floor, New York, New York 10014; Jefferies LLC, Attention: Equity Syndicate Prospectus Department, 520 Madison Avenue, 2nd Floor, New York, NY 10022, or by telephone at (877) 821-7388, or by email at [email protected]; or Leerink Partners LLC at Attention: Syndicate Department, One Federal Street, 37th Floor, Boston, MA 02110, by telephone at (800) 808-7525 extension 6132 or by email at [email protected].

This press release shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of, the securities being offered in any state or other jurisdiction in which such offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of any such state or other jurisdiction.

About Epizyme, Inc.
Epizyme, Inc. is a clinical-stage biopharmaceutical company committed to rewriting cancer treatment through novel epigenetic medicines. Epizyme is broadly developing its lead product candidate, tazemetostat, a first-in-class EZH2 inhibitor, with studies underway in both solid tumors and hematological malignancies, as a monotherapy and combination therapy and in relapsed and front-line disease. Using the Company's proprietary platform, Epizyme has pioneered the identification and development of small molecule inhibitors of chromatin modifying proteins (CMPs), such as tazemetostat. CMPs are part of the system of gene regulation, referred to as epigenetics, that controls gene expression. Genetic alterations can result in changes to the activity of CMPs, which can allow cancer cells to grow and proliferate. By focusing on the genetic drivers of cancers, Epizyme's science seeks to match targeted medicines with the specific patients that need it.

Cautionary Note on Forward-Looking Statements
Any statements in this press release about future expectations, plans and prospects for Epizyme, Inc., including statements about the Company's anticipated use of proceeds from the offering, future operations, clinical development of the Company's therapeutic candidates, expectations regarding future clinical trials and future expectations and plans and prospects for the Company 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: uncertainties related to market conditions, uncertainties inherent in the initiation of future clinical trials, and other factors discussed in the "Risk Factors" section of the preliminary prospectus filed with the SEC on September 13, 2017, the Company's most recent Form 10-Q filed with the SEC and in other filings the Company makes from time to time with the SEC. In addition, the forward-looking statements included in this press release 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, except as required by law.

Contact:
Monique Allaire, THRUST IR
[email protected]
(617) 895-9511