Doxifluridine


Doxifluridine is a second generation nucleoside analog prodrug developed by Roche and used as a cytostatic agent in chemotherapy in several Asian countries including China and South Korea. Doxifluridine is not FDA-approved for use in the USA. It is currently being evaluated in several clinical trials as a stand-alone or combination therapy treatment.

Biology

5-Fluorouracil, the nucleobase of doxifluridine, is currently an FDA-approved antimetabolite. 5-FU is normally administered intravenously to prevent its degradation by dihydropyrimidine dehydrogenase in the gut wall. Doxifluridine is a fluoropyrimidine derivative of 5-FU, thus a second-generation nucleoside prodrug. Doxifluridine was designed to improve oral bioavailability in order to avoid dihydropyrimidine dehydrogenase degradation in the digestive system.
Within a cell, pyrimidine nucleoside phosphorylase or thymidine phosphorylase can metabolize doxifluridine into 5-FU. It is also a metabolite of capecitabine. High levels of pyrimidine-nucleoside phosphorylase and thymidine phosphorylase are expressed in esophageal, breast, cervical, pancreatic, and hepatic cancers. Liberation of 5-FU is the active metabolite and leads to inhibition of DNA synthesis and cell death.

Side effects

High thymidine phosphorylase expression is also found in the human intestinal tract, resulting in dose-limiting toxicity in some individuals.
The most frequent adverse effects for doxifluridine were neurotoxicity and mucositis.

Brand names

Doxifluridine is sold under many brand names:
Brand nameCompanyCountry
DidoxShin Poong Pharm. Co., Ltd.South Korea
DoxyfluridineKwang DongSouth Korea
Doxifluridine capMyungmoon Pharma Co. Ltd.South Korea
Ai FengHengruiChina and Japan
DoxifluridineXinShiDai PharmaceuticalChina and Japan
FurtulonRoche, ChugaiChina and Japan
Ke FuZhaohuiChina and Japan
Ke TuoSouthwestChina and Japan
Qi Nuo Bi TongWanjie High-TechChina and Japan
Shu QiTeamChina and Japan
Tan NuoXinchang Medicine & Chemical Co LtdChina and Japan
Yi Di AnPacificChina and Japan