TOKYO (

TheStreet

) --

Pfizer

(PFE) - Get Report

plans to start selling generic drugs in Japan beginning in 2011.

"Pfizer is considering entering the generic drug market in Japan as it seeks to diversify its business operations to build a stronger earnings structure," a spokesman at Pfizer's Japan unit told

Reuters

. The spokesman added the world's biggest drugmaker will prioritize its patented drugs.

The Japanese market for generic drugs is expected to total 515 billion yen ($5.8 billion) in the year to March 2010 and to expand to 705 billion yen in three years, according Japan's leading generic drugmaker

Sawai Pharmanceutical

,

Reuters

reports.

News of Pfizer's potential move was first reported by Japan's business daily

Nikkei

.

Pfizer's unit it Japan will establish a division on Dec. 1 dedicated to drugs whose patents have expired,

Nikkei

reports.

The division will first handle sales of roughly 70 Pfizer drugs on which the patents have expired, and is expected later to apply for sales licenses for generic drugs based on other firms' expired patents and begin selling them once it receives approvals.

-- Reported by Joseph Woelfel in New York

.

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