Epizyme Announces Presentation Of Data From Phase 1 Study Of EZH2 Inhibitor EPZ-6438 (E7438)

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Epizyme, Inc. (NASDAQ: EPZM), a clinical stage biopharmaceutical company creating innovative personalized therapeutics for patients with genetically defined cancers, announced today that updated data from the ongoing Phase 1 dose escalation study of EPZ-6438 (referred to as E7438 by Epizyme's partner Eisai) were presented by Vincent Ribrag, M.D., Institut Gustave Roussy at the 13^th International Congress on Targeted Anticancer Therapies in Paris, France. EPZ-6438, a first-in-class, oral EZH2 inhibitor, is being investigated in patients with advanced B-cell non-Hodgkin lymphomas (NHL) and solid tumors.

In his presentation, Professor Ribrag principally reviewed the EPZ-6438 dose escalation data that were previously presented at the EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics in November 2014, including safety and efficacy data as of an October 20, 2014 data cut-off. Professor Ribrag also presented the following updates to the earlier data:

• Following a review of the data presented in November 2014, the response in one patient with an INI1-deficient malignant rhabdoid tumor that had previously been classified and reported as a partial response was re-classified to a complete response; as of January 23, 2015, this patient remained on study after 35 weeks
• Four of the 10 evaluable patients with NHL reported on in November 2014 continue on study, with time on study ranging from 29 weeks to 59 weeks as of January 23, 2015

As reported in November 2014, all of the NHL patients enrolled in the dose escalation cohorts who underwent central testing had wild-type EZH2, and responses were seen in germinal center origin and non-germinal center origin disease.

Epizyme and Eisai are currently enrolling up to 12 additional patients in the expansion cohorts of this Phase 1 trial.

About EZH2 Cancers
EZH2 is a histone methyltransferase (HMT) that is increasingly understood to play a potentially oncogenic role in a number of cancers. These include non-Hodgkin lymphomas and INI1-deficient cancers such as synovial sarcoma and malignant rhabdoid tumors.

About EPZ-6438
Epizyme and its partner Eisai are developing EPZ-6438 (E7438) for the treatment of non-Hodgkin lymphoma patients and patients with INI1-deficient solid tumors. EPZ-6438 is a small molecule inhibitor of EZH2 developed by Epizyme. In many human cancers, misregulated EZH2 enzyme activity results in misregulation of genes that control cell proliferation—without these control mechanisms, cancer cells are free to grow rapidly.

Epizyme granted Eisai a worldwide license to EPZ-6438, subject to Epizyme's right to opt in for co-development, co-commercialization and profit share arrangement with Eisai in the United States. Epizyme is working with Roche and Eisai to develop a companion diagnostic to identify patients with non-wild type EZH2, where EZH2 contains point mutations. Additional information about these partnerships may be found here: http://www.epizyme.com/about-us/partnerships/

EPZ-6438 is the second HMTi to enter human clinical development (following Epizyme's DOT1L inhibitor, EPZ-5676).

Additional information about this program, including clinical trial information, may be found here: http://clinicaltrials.gov/ct2/show/NCT01897571?term=7438&rank=1

About Epizyme, Inc.
Epizyme, Inc. is a clinical stage biopharmaceutical company creating personalized therapeutics for patients with genetically defined cancers. Epizyme has built a proprietary product platform that the company uses to create small molecule inhibitors of a 96-member class of enzymes known as histone methyltransferases, or HMTs. HMTs 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 HMTs, making them oncogenic (cancer-causing). By focusing on the genetic drivers of cancers, Epizyme's targeted science seeks to match the right medicines with the right patients for a personalized approach to cancer treatment.

For more information, visit www.epizyme.com and connect with us on Twitter at @EpizymeRx.

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