SUPREME COURT OF JAPAN RULES TO EXTEND EISAI'S PATENT FOR ARICEPT® IN RELATION TO SEVERE ALZHEIMER'S DISEASE

Eisai Co., Ltd. (Headquarters: Tokyo, President & CEO: Haruo Naito) announced today that the Supreme Court of Japan has turned down a petition filed by generic drug manufacturers in regards to an Intellectual Property High Court ruling to maintain a decision to grant an extension for the Aricept® (donepezil hydrochloride) patent in relation to severe Alzheimer's disease.

On February 22, 2011, the Intellectual Property High Court of Japan ruled in a trial to maintain the decision made by the Japan Patent Office to maintain the patent term extension, which would effectively see the patent term for Aricept® in relation to severe Alzheimer's disease be extended until June 22, 2013.

In response to this ruling by the Intellectual Property High Court of Japan, a number of generic drug manufacturers filed a petition dated March 8, 2011, however, on September 9, 2011, the Supreme Court handed down its decision to turn down this request for an appeal hearing. As a result of this decision, the term of the Aricept® patent in relation to severe Alzheimer's disease was extended to June 22, 2013.

Aricept® is the only drug in Japan to be approved for all stages of Alzheimer's disease－mild to severe. Eisai remains committed to making further contributions to increase the benefits provided to an even greater number of Alzheimer's patients, their families and caregivers.