NCI Drug Dictionary

The NCI Drug Dictionary contains technical definitions and synonyms for drugs/agents used to treat patients with cancer or conditions related to cancer. Each drug entry includes links to check for clinical trials listed in NCI's List of Cancer Clinical Trials.

tegafur-gimeracil-oteracil potassium-leucovorin calcium oral formulation
An orally bioavailable granular formulation composed of the fluoropyrimidine antagonist tegafur combined with two modulators of 5-fluorouracil (5-FU) activity, gimeracil and oteracil potassium, and the folic acid derivative leucovorin calcium, with potential antineoplastic activity. Tegafur is a prodrug of 5-fluorouracil (5-FU), an antimetabolite that is further metabolized to 5-fluoro-2'-deoxyuridine monophosphate (FdUMP) and 5-fluorouridine triphosphate (FUTP). FdUMP inhibits thymidylate synthase, DNA synthesis and cell division; FUTP competes with uridine triphosphate (UTP), thus inhibiting RNA and protein synthesis. Gimeracil is a reversible inhibitor of dihydropyrimidine dehydrogenase (DPD), the liver enzyme responsible for rapid catabolism of 5-FU into inactive metabolites. Oteracil potassium preferentially localizes in the gut and inhibits the enzyme orotate phosphoribosyl-transferase (OPRT), which converts tegafur to 5-FU. This decreases the amount of 5-FU in the gut and prevents activated 5-FU-related gastrointestinal (GI) toxicity. Leucovorin calcium, an active metabolite of folic acid, counteracts the toxic effects of 5-FU, thereby 'rescuing' the patient while permitting the antitumor activity of 5-FU. Check for active clinical trials using this agent. (NCI Thesaurus)

Code name:TAS-118