EISAI'S U.S. SUBSIDIARY EISAI INC. ENTERS SHARE PURCHASE AGREEMENT CONCERNING AKARX INC. IN THE U.S.RIGHTS TO IN-HOUSE DEVELOPED THROMBOCYTOPENIA TREATMENT AVATROMBOPAG TO BE TRANSFERRED

Listed Company Name:Eisai Co., Ltd.
Representative:Haruo Naito
Representative Corporate
Officer and CEO
Securities Code:4523
Stock Exchange Listing:First Section of the Tokyo
Stock Exchange
Inquiries:Sayoko Sasaki
Vice President, Corporate Affairs
Phone +81-3-3817-5120

Eisai Co., Ltd. (Headquarters: Tokyo, CEO: Haruo Naito, “Eisai”) announced today that its U.S. subsidiary Eisai Inc. has entered into a share purchase agreement concerning the transfer of all the shares of AkaRx, Inc. (“AkaRx”) held by Eisai Inc. to PBM Capital Group, LLC. (Location: Virginia, United States, “PBM”).

According to the agreement, Eisai Inc. will transfer to PBM ownership of AkaRx and the worldwide rights to develop, market and manufacture the investigational thrombocytopenia treatment avatrombopag (generic name, development code: E5501). Eisai Inc. will receive an upfront payment from PBM as well as milestone payments in line with commercialization of avatrombopag.

Avatrombopag is a novel, oral thrombopoietin receptor agonist that stimulates platelet production and is currently being investigated in a Phase Ⅲ clinical study as a possible treatment for thrombocytopenia in patients with chronic liver disease undergoing an elective procedure, conducted in Japan, the United States, Europe and Asia. Moving forward, the conduct of this study will be handled by PBM.

Eisai positions oncology and neurology as its key therapeutic areas, and has been revising its business portfolio. By transferring the shares of AkaRx to PBM, Eisai intends to focus its management resources on oncology and neurology.

The impact of this transfer on Eisai's consolidated financial results has been incorporated into the Notification Regarding Revision of Consolidated Financial Results Forecasts (IFRS) for the Fiscal Year Ending March 31, 2016 announced today.

< Notes to editors >

1. About avatrombopag (generic name, development code: E5501)

Avatrombopag is a novel, oral thrombopoietin receptor agonist, which is believed to stimulate platelet production acting on megakaryocytes and their precursors. In January 2010, Eisai acquired all outstanding shares of AkaRx, Inc., including the worldwide rights to develop, market and manufacture avatrombopag, which was a pipeline product of AkaRx, Inc. The agent is currently being investigated in a Phase Ⅲ clinical study as a possible treatment for thrombocytopenia in patients with chronic liver disease undergoing an elective procedure, conducted in Japan, the United States, Europe and Asia.

2. About PBM Capital Group LLC

PBM Capital Group LLC. is a private investment firm primarily focused on healthcare investments. Led by Paul Manning, a successful entrepreneur, the PBM Capital Group partners with exceptional scientists, engineers and entrepreneurs who have developed game-changing technology that can improve and save the lives of millions of people. The goal is to create financially strong companies that change the way we live our lives through science, innovation, and creativity. PBM creates value by applying extensive industry knowledge and contacts, providing superior operational expertise and bringing entrepreneurial spirit to attractive investment opportunities. Visit www.pbmcap.com for more information.

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