The results of the clinical trial on the effects of ARICEPT (donepezil) led by AD2000 collaborative group of University of Birmingham, UK, appeared in the June 26, 2004 issue of The Lancet, a medical journal published in the UK.

The AD2000 trial is a placebo-controlled study which aimed to assess the effects of donepezil from the viewpoint such as patient institutionalisation, and concludes that donepezil is not cost effective. Eisai and Pfizer Limited have reviewed the results of the study, and set the results of this new information in context with all other published evidence.

In the donepezil study programs involving a total of 15,000 patients, ARICEPT has shown improvements in cognitive impairment of Alzheimer's disease and effectiveness in improving neuro-psychiatric symptoms. ARICEPT has also shown to delay nursing home placement of almost two years and slows down decline in ADL function, in patients with mild to moderate AD.

The AD2000 trial was planned to recruit 3000 patients over a year to detect differences between donepezil and placebo. However, only 565 patients were randomized such that we recognize the study is under-powered, and results have limited value when compared to the extensive data with donepezil in over 15,000 patients. Hence we believe that the reported results of AD2000 do not provide the effectiveness of ARICEPT accurately compared with accepted findings derived from carefully monitored and validated studies.

In Europe, ARICEPT has received EU regulatory approval with submission of the studies in the donepezil clinical trial program, which were conducted to the standards of Good Clinical (Research) Practice. In the UK, ARICEPT gained the endorsement of National Institute for Clinical Excellence (NICE), which critically assesses the clinical usefulness and cost effectiveness of new drugs.

Eisai and Pfizer are confident of the effectiveness of ARICEPT as the No.1 prescribed treatment of Alzheimer's disease supported by the rich evidence reported in 14 double-blind studies and long-term clinical studies.

Contacts:

Eisai Co., Ltd.
Corporate Communications Department
Phone 03-3817-5120 (Tokyo)