Weekly chronomodulated 48 h infusion of high-dose 5-fluorouracil modulated by methotrexate and (6S)-leucovorin in advanced colorectal cancer: a phase IB study

In this phase IB study, 24 patients with advanced colorectal cancer were treated with escalating doses of weekly chronomodulated 48 h infusions of 5-fluorouracil (5-FU) biochemically modulated by methotrexate 40 mg/m2 and (6S)-leucovorin 8 x 45 mg orally. Two daily peak delivery periods (PDP), during which 65% of the daily dose was administered, were investigated: from 18.00 to 0.30 h and from 0.00 to 06.30 h. The maximal tolerated dose of 5-FU was 2800 mg/m2/48 h, with a PDP from 18.00 to 0.30 h