Doxifluridine (AMC 0101) is a fluoropyrimidine derivative and oral prodrug of the antineoplastic agent 5-fluorouracil (5-FU) with antitumor activity. Doxifluridine, designed to circumvent the rapid degradation of 5-FU by dihydropyrimidine dehydrogenase in the gut wall, is converted into 5-FU in the presence of pyrimidine nucleoside phosphorylase. 5-FU interferes with DNA synthesis and subsequent cell division by reducing normal thymidine production and interferes with RNA transcription by competing with uridine triphosphate for incorporation into the RNA strand.

Doxifluridine suppresses tube formation of HUVEC and vascular endothelial growth factor production by FU-MMT-1 cells. [1] Doxifluridine is converted to 5-FU and subsequently to FdUMP, and the results suggest that Doxifluridine exerts its cytotoxic effects through inhibition of TS and incorporation into RNA. [2] Doxifluridine is a fluoropyrimidine derivative that is activated preferentially in malignant cells by thymidine phosphorylase to form 5-fluorouracil (5-FU). Doxifluridine is developed to improve the therapeutic index of 5-FU and to reduce toxicity, including the immunosuppressive, myelosuppressive, and cardiotoxic effects of 5-FU and other fluorinated pyrimidines. [3]

Metronomic Doxifluridine alone significantly suppresses tumor growth compared with the untreated (control) group, while metronomic Doxifluridine in combination with TNP-470 significantly inhibits tumor growth compared with each treatment alone in in FU-MMT-1 xenografts. Doxifluridine in combination with TNP-470 also leads to a significant reduction of intratumoral vascularity. [1] Doxifluridine significantly inhibits the growth of KPL-4 tumors, reduces the tissue levels of IL-6, and alleviates body weight loss in nude mice bearing KPL-4 tumors. [4] Doxifluridine results in a significant reduction in the activity of phenytoin p-hydroxylation in rats. Doxifluridine decreases the elimination rate constant and the total clearance in rats. [5]