FOR IMMEDIATE RELEASE
No.06-20
May 16, 2006

Eisai Co., Ltd. (Headquarters: Tokyo, President and CEO: Haruo Naito) announced today that its U.K. subsidiary Eisai Ltd. (Headquarters: London, Managing Director: Paul Hooper) filed an application with the MHRA (Medicines and Healthcare Products Regulatory Agency) for a new indication of severe Alzheimer's disease for Aricept through the Mutual Recognition Procedure in Europe and the 12 Member States involved in the procedure on May 15, 2006 (local time).

The application includes the results of three 6-month placebo-controlled, randomized double-blind studies with severe Alzheimer's disease patients in Sweden, the U.S.¹, and Japan. In these studies, Aricept was found to be statistically significant on the cognitive function as measured on the SIB². In addition, Aricept showed a statistically significant effect or improvement tendency in ADCS-ADL-severe³ or CIBIC-plus⁴, compared to placebo.

Aricept, an acetylcholinesterase inhibitor developed by Eisai Co., Ltd. in Japan, is used in the treatment of mild to moderate Alzheimer's disease and increases the concentration of acetylcholine, a neurotransmitter in the brain. It is estimated that there are about 4.5 million patients with Alzheimer's disease in Europe.

With this application, Eisai is seeking to contribute to a wider population of patients and their caregivers by providing Aricept as first-line therapy for all patients with Alzheimer's disease including those patients with severe symptoms.

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Contacts:
Corporate Communications Department
Eisai Co., Ltd.
TEL: 81-3-3817-5120