For Immediate Release

Representative: Takashi Shoda, President and Representative Director
(Code no.: 4568, First Section, Tokyo, Osaka and Nagoya Stock Exchanges)
Please address inquiries to Toshiaki Sai, General Manager,
Corporate Communications Department
Telephone: +81-3-6225-1126
http://www.daiichisankyo.com/

Regarding the Lawsuit to Revoke the Decision to Nullify a Portion of the Patent Term Extension for Levofloxacin in Japan

Tokyo, Japan (November 9, 2009) - Daiichi Sankyo Company, Limited (TSE: 4568), announced today that it has brought a lawsuit before the Intellectual Property High Court (hereinafter, the High Court) to have the decision to nullify a portion of the patent term extension for Levofloxacin Hydrate revoked. However, on October 28, 2009, the High Court issued its ruling to sustain the decision. In view of this ruling, the company had considered to appeal its case to the Supreme Court, but wishes to herewith announce that it has decided not to appeal its case.

The patent numbers for the Levofloxacin Hydrate preparation (brand name: Cravit® Tablets and Cravit® fine granules) are No.2008845 for the compound patent and No.1659502 for the use patent (hereinafter, referred to collectively as the Patents). Based on an approval for an additional indication of Levofloxacin Hydrate for the treatment of genus Legionella, an extension of the term of the Patents until May 27, 2011, was granted following an examination by the Patent Office. However, 13 generic drug manufacturers requested the nullification of this extension of the term of the Patents on the grounds that the extension was invalid. At the end of November 2008, the Patent Office made a decision that extending the term of the Patents beyond December 25, 2008, corresponding to the terms for overseas clinical trials and the like, was invalid.

Daiichi Sankyo brought a lawsuit before the High Court on December 24, 2008, requesting that the said invalidation decision be revoked on the grounds that it was in error. However, as noted previously, unfortunately, the High Court issued a ruling to sustain the invalidation decision.

Going forward, the Company will continue to endeavor to develop and maintain efficacious intellectual properties.