First author of the 1996 paper describing S-1
T. Shirasaka
First author of the 1996 Anti-Cancer Drugs paper that proposed S-1, a combination of tegafur, CDHP and potassium oxonate. In a 2009 review he writes that his group invented S-1 in 1991 and lists him as leader of the S-1 project established in November 1990.
Sources
Shirasaka T, Shimamato Y, Ohshimo H, Yamaguchi M, Kato T, Yonekura K, et al. Development of a novel form of an oral 5-fluorouracil derivative (S-1) directed to the potentiation of the tumor selective cytotoxicity of 5-fluorouracil by two biochemical modulators. Anticancer Drugs. 1996;7(5):548-57.
Shirasaka T. Development history and concept of an oral anticancer agent S-1 (TS-1): its clinical usefulness and future vistas. Jpn J Clin Oncol. 2009;39(1):2-15.