Eisai Company, Ltd.'s sNDA Filing For ARICEPT(R) In The Treatment Of Severe Alzheimer's Disease Not Accepted By FDA

TOKYO, and TEANECK, N.J., Oct. 27 /PRNewswire-FirstCall/ -. Eisai Co., Ltd. and Eisai Inc. (Headquarters: Teaneck, NJ, Chairman and CEO Hajime Shimizu) announced today that the U.S. Food and Drug Administration (FDA) did not accept a supplemental New Drug Application (sNDA) for ARICEPT(R) (donepezil HCl tablets) for treatment of severe Alzheimer's disease (AD) because of deficiencies in the format of the application. ARICEPT, which is co-promoted in the United States by Eisai Inc. and Pfizer Inc, is currently approved for treatment of mild to moderate AD. Eisai Medical Research Inc. (Headquarters: Ridgefield Park, President Mindell Seidlin, MD), which submitted the sNDA on behalf of Eisai Co., Ltd. and Eisai Inc. on August 31, 2005, plans to resolve these issues and resubmit the sNDA in mid-December 2005.

Information about the ARICEPT sNDA Submission

The submission was based on results of a pivotal six-month, multi-center, randomized, double-blind, placebo-controlled clinical trial involving 248 nursing home patients with severe AD (Mini Mental State Exam scores 1-10). The patients treated with 10 mg. ARICEPT had statistically significant improvement compared to those taking placebo on both primary efficacy measures: cognition; the Severe Impairment Battery (SIB scale) and function/activities of daily living; the Modified Alzheimer's Disease Cooperative Study Activities of Daily Living Inventory for Severe Alzheimer's Disease. Treatment with ARICEPT was generally well tolerated. The most common adverse events in ARICEPT-treated patients reported at more than twice the rate of placebo-treated patients were diarrhea and hallucinations. The rate of discontinuation for adverse events was greater in the ARICEPT-treated patients than in the placebo-treated patients (15.6 % vs 6.7%).

AD is a progressive brain disease that gradually destroys a person's memory and ability to learn, reason, make judgments, communicate and carry out daily activities. AD affects 4.5 million Americans. One in 10 persons over age 65 has AD, and nearly half of those over 85 have it.

Information about ARICEPT Treatment in Alzheimer's Disease

While there is no cure for Alzheimer's disease, medical treatments are available to manage symptoms of the disease. Once-a-day prescription ARICEPT is indicated for mild to moderate Alzheimer's disease.

ARICEPT is an acetylcholinesterase inhibitor and is believed to work by inhibiting the breakdown of acetylcholine, thereby increasing available levels of this chemical in the brain. There is an established association between the loss of acetylcholine, a brain chemical involved in memory and thinking, and Alzheimer's disease.

In a progressively degenerative disease such as Alzheimer's, improvement, stabilization, or a less-than-expected decline over time is considered a positive response to treatment. These types of responses have been observed in patients treated with ARICEPT in clinical trials for Alzheimer's disease. Individual responses to treatment vary, and some patients may not respond.

ARICEPT is the number one prescribed Alzheimer's disease therapy worldwide, with more than 2.5 billion patient days of ARICEPT therapy. Nearly 2.3 million people in the United States alone have taken ARICEPT.

ARICEPT is well tolerated but may not be for everyone. Some people may have nausea, diarrhea, not sleep well or vomit. Some people may have muscle cramps, feel very tired, or may not want to eat. In studies, these side effects were usually mild and went away over time. People at risk for stomach ulcers or who take certain other medicines should tell their doctors because serious stomach problems, such as bleeding, may get worse. Some people who take ARICEPT may experience fainting.

ARICEPT is co-promoted in the United States by Eisai Inc. and Pfizer Inc, which are dedicated to advances in Alzheimer's therapy. For more information about managing Alzheimer's disease and about ARICEPT, and for prescribing information on ARICEPT, please see full prescribing information at http://www.aricept.com.

About Eisai Co., Ltd.

Eisai Co., Ltd. is a research-based human health care company that discovers, develops and markets products in more than 30 countries. Through a global network of research facilities, manufacturing sites and marketing subsidiaries, Eisai actively participates in all aspects of the worldwide health care system. Eisai employs more than 8,000 people worldwide.

About Eisai Inc.

Eisai Inc. is a U.S. pharmaceutical subsidiary of Eisai Co., Ltd. Established in 1995, Eisai Inc. began marketing its first product in the United States in 1997 and has rapidly grown to become an integrated pharmaceutical business with sales of approximately $2 billion in fiscal year 2004 (year ended March 31, 2005).

About Eisai Medical Research Inc.

Eisai Medical Research Inc. is a U.S. pharmaceutical subsidiary of Eisai Co., Ltd. Eisai Medical Research Inc. was established to focus solely on clinical research and to expedite clinical drug development of new chemical entities and of new indications for marketed products.

About Pfizer Inc

Pfizer Inc discovers, develops, manufactures and markets leading prescription medicines for humans and animals and many of the world's best- known consumer brands.

Eisai Co., Ltd.; Eisai Inc.

CONTACT: Judee Shuler of Eisai, +1-201-287-2241

Web site: http://www.aricept.com//