News Release

Taiho announces today that sanofi-aventis is returning its territory rights to Taiho Pharmaceutical Co., Ltd. for the development and commercialization of the oral anti-cancer agent S-1.
Taiho will pursue further development of S-1 outside of Japan with gastric cancer included.

S-1 is an oral fluorouracil anticancer product that combines 3 pharmacological agents in a certain ratio: tegafur which is a pro-drug of 5 fluoro-uracil; gimeracil (5-chloro-2,4 dihydropyridine (CDHP)) which inhibits dihydropyrimidine dehydrogenase (DPD) enzyme activity; and oteracil (potassium oxonate (Oxo)) a gastrointestinal side effects corrector.

S-1 has been commercialized in Japan by Taiho Pharmaceuticals since 1999 for the treatment of gastric, colorectal, head and neck, non-small cell lung, metastatic breast, pancreas and biliary tract cancers.

Taiho Pharmaceutical Co., Ltd. (Taiho) is a company engaged in discovery, development, manufacturing and marketing of pharmaceutical products, with its headquarters in Tokyo, Japan. Taiho is one of the leading companies focused on oncology. For more information about Taiho, please visit the company's Web site at www.taiho.co.jp/english/index.html.

Atsushi Azuma
Product Research, Licensing & Alliance Management
Taiho Pharmaceutical Co., LTD.
Tel: #81-3-3294-4527
1-27, Kandanishiki-cho, Chiyoda-ku, Tokyo, 101-8444, Japan