Phase I and pharmacokinetic evaluation of floxuridine/leucovorin given on the Roswell Park weekly regimen

Abstract

A phase I and pharmacokinetics study was carried out of floxuridine (FdUrd) modulated by leucovorin (LV) given on the Roswell Park regimen (LV given at 500 mg/m2 by 2-h infusion and FdUrd given by i.v. push at 1 h after the start of LV infusion, treatment being given weekly×6). The dose-limiting toxicity was diarrhea; the MTD and recommended dose for phase II studies was 1,650 mg/m2 per week of FdUrd. The dose-response curve was steep, with 3/3 patients treated at a dose of 1,750 mg/m2 developing grade IV diarrhea. With this schedule there was no significant mucositis. Pharmacokinetic parameters showed very wide interpatient variability. Plasma decay was biphasic with a t1/2β of approximately 2 h. Plasma clearance was high (>200 l h-1). No correlation between pharmacokinetic parameters and toxicity could be identified. © 1994 Springer-Verlag.