Phase I/II study of twenty-four-hour infusion of irinotecan in combination with oral UFT plus leucovorin for metastatic colorectal cancer.

ABSTRACT

OBJECTIVE: Irinotecan has, in general, been administered as a 90-min infusion. However, several studies have demonstrated that continuous infusion seems to be a promising method of delivering irinotecan. This phase I/II trial was performed to evaluate the efficacy and safety of continuous infusion of irinotecan combined with UFT plus leucovorin (LV) for metastatic colorectal cancer. METHODS: Escalating doses of irinotecan (90-110 mg/m(2)) were administered by 24-hour infusion on day 1. UFT 300 mg/m(2)/day and LV 75 mg/day were administered orally, in 3 divided daily doses, on days 3-7 and 10-14. The treatment cycles were repeated every 2 weeks. RESULTS: In the phase I study, the maximum tolerated dose of irinotecan was 110 mg/m(2) and the recommended dose for the phase II study was determined to be 100 mg/m(2). Thirty-six patients, including 3 patients at the recommended dose in the phase I study, were evaluated in the phase II study. The common grade 3/4 toxicities were leucopenia, neutropenia, diarrhea and anorexia. The response rate was 63.9%, and the median progression-free and overall survival times were 8.3 and 24.6 months, respectively. CONCLUSION: A 24-hour infusion of irinotecan combined with UFT/LV is feasible and active for metastatic colorectal cancer.