UPDATE 1-Eisai withdraws Aricept's EU new use application

(Adds reason for withdrawal, background)

TOKYO, April 13 (Reuters) - Japanese drug maker Eisai Co. Ltd. (4523.T) said on Friday it had tentatively withdrawn its European application for its Alzheimer's drug Aricept to be also used to treat severe forms of the disease.

European regulators requested more data showing Aricept led to improvements in daily life activities of patients with severe Alzheimer's, said company spokesman Takeshi Shimizu.

They were, however, satisfied with the data relating to improvements in cognition, he said.

Eisai, Japan's fourth-biggest pharmaceutical firm, said it would discuss the matter with regulatory authorities and review possibilities for resubmission.

The use of Aricept -- a blockbuster drug which is the company's main earnings driver -- for the treatment of severe Alzheimer's disease has already been approved in the United States, India, New Zealand and the Philippines.

Some 2.4 million people are estimated to have Alzheimer's disease in Europe's five main markets, Germany, France, the U.K, Italy and Spain, with 13 percent suffering from the severe form of the disease.

There is no cure for the condition, typified by memory loss and other cognitive impairment that can quickly worsen. Alzheimer's is the most common form of dementia.

Eisai said the tentative withdrawal of the application would not affect its mid-term earnings targets.

The drug maker has also submitted an application for the additional indication in Japan.

((Reporting by Edwina Gibbs, editing by Sophie Hardach; Reuters messaging: edwina.gibbs.reuters.com@reuters.net; email edwina.gibbs.@reuters.com; +81 3 3432-8720)) Keywords: EISAI DRUG/

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