Eisai Co., Ltd. (Headquarters: Tokyo, President & CEO: Haruo Naito, “Eisai”) announced today that the company has entered into a worldwide partnership with U.S.-based Epizyme, Inc. (Headquarters: Cambridge, Massachusetts, President: Robert Gould, Ph.D., “Epizyme”) to discover, develop and commercialize therapeutics targeting EZH2, an epigenetic enzyme, for the treatment of lymphoma and other cancers in genetically-defined patients.

Eisai was led to Epizyme as the partner of choice for this strategic epigenetic drug discovery agreement due to its proprietary product platform; leadership in determining the oncogenic role of EZH2 in genetically-defined cancers; and success in discovering novel, potent, and selective small molecule inhibitors of histone methyltransferases (HMTs), an important epigenetic target class.

Under the terms of the agreement, Eisai will pay Epizyme an upfront payment, as well as additional research, development and sales milestones in accordance with project progress, and royalties. Additionally, Eisai will fund 100 percent of R&D through human proof of concept, while Epizyme has the right to opt into a co-commercialization arrangement for the United States. And this agreement is made effective as of the 1st day of April, 2011.

In recent years, remarkable advancements have been made in the understanding of the role that genes play in human cancer. Utilizing the genetic approach undertaken by H3 Biomedicine Inc. an Eisai research and development subsidiary established in December 2010, to identify medicinal targets from genome information related to the genetic alteration of the cancer cells, together with Epizyme's epigenetic-based drug discovery approach to selectively activate or inactivate the gene function in cancer cell targeting HMTs, will make it possible to identify specific disease targets and will lead to a significant improvement in Eisai's target validation capabilities. It is also expected that these approaches will further enhance the company's capability to create new compounds that can be used to provide cancer patients with individualized care (personalized medicine).

Eisai defines oncology as a therapeutic area of focus and is committed to the development of novel anticancer agents and treatments for supportive care. Through this new partnership, Eisai seeks to make further contributions to addressing the diversified needs of and increasing the benefits provided to cancer patients and their families as well as healthcare professionals.

[ Please refer to the following notes for further information on Epizyme, Inc. ]

Media Inquiries:

Public Relations Department,
Eisai Co., Ltd.

< Notes to editors >

1.About Epizyme, Inc.

Epizyme, Inc. is leading the discovery and development of small molecule histone methyltransferase (HMT) inhibitors, a new class of targeted therapeutics for the treatment of genetically-defined cancer patients based on breakthroughs in the field of epigenetics. Genetic alterations in the HMTs are strongly associated with the underlying causes of multiple human diseases, including cancer. Epizyme's patient-driven approach represents the future of personalized therapeutics by creating better medicines for the right patients more quickly and at lower cost than traditional approaches.

2.About epigenetics

Epigenetics is a branch of science that studies the mechanism for selective activation/inactivation of the gene function and seeks to determine how gene function is altered through cell division, irrespective of DNA base sequence alteration. The overall epigenetic state of a genome is referred to as “epigenome”.

3.About EZH2

EZH2 participates in the modulation of epigenetic gene expression as a member of gene expression modulation protein complex called polycomb protein. EZH2 methylates lysine (27) in the histone H3 core protein and inhibits gene transcription in the region.

4.About H3 Biomedicine Inc.

H3 Biomedicine Inc. is a biopharmaceutical company that specializes in the discovery and development of cancer drugs. The company aims to use the latest synthetic chemistry, chemical biology, and human genome information in order to create next-generation cancer drugs with the objective of improving the quality of life of cancer patients. It is a subsidiary of Eisai Co., Ltd.'s U.S. affiliate Eisai Inc. and based in Cambridge, Massachusetts.