Tài liệu Báo cáo y học: "Effects of Bolus Injection of 5-Fluorouracil on Steady-State Plasma Concentrations o

The oral fluoropyrimidine UFT and capecitabine have been developed to improve tolerability and patient convenience, and have replaced continuous infusion of 5-FU in many treatment regimens [5]. UFT is a combination of tegafur, an oral prodrug of 5-FU, and uracil in a molar ratio of 1: 4. Tegafur produces a constant reserve of 5-FU and its active metabolites, and provides pharmacokinetics equivalent to the constant infusion of 5-FU. Uracil is an endogenous substrate for dihydropyrimidine dehydrogenase, the main enzyme responsible for the degradation of 5-FU, and enhances the anticancer effects of 5-FU. In reports published in 2002, UFT with LV proved comparable with bolus 5-FU/LV-based regimens in two multicenter, randomized phase III trials [6,7]. Subsequently, a number of phase II clinical trials have demon-strated the efficacy and tolerability of UFT in combination with CPT-11 or L-OHP in the first-line treatment of metastatic colorectal cancer [8-14]. The novel regimens have been referred to as TEGAFIRI and TEGAFOX, respectively.