Background: There is evidence that continuous infusion allows the delivery of higher doses of a drug while reducing the incidence of neurologic and renal toxicity. To verify prior to phase II testing the feasibility of ambulatory treatment with high-dose ifosfamide/mesna by continuous infusion in adult solid tumours, the maximum tolerated dose (MTD) and the non-haematological dose-limiting toxicities for the achievement of 2 courses of therapy were determined.
Patients and methods: Thirty-two patients with advanced solid tumours were given continuous-infusion ifosfamide, from 9 to 16 g/m2, over 4 consecutive days, with equidose mesna uroprotection and granulocyte colony-stimulating-factor support; courses were repeated every 3 weeks. Total dose/course was escalated by 1 g/m2, in cohorts of 3 to 5 patients until the MTD was determined.
Results: At 16 g/m2, the dose-limiting toxicity was renal, with 2 of the 5 patients treated developing renal failure. Haematological toxicity was dose-related and significant at higher dosages, but generally surmountable. Ifosfamide at 15 g/m2/course with mesna uroprotection was identified as the MTD.
Conclusions: The present study shows that high-dose continuous-infusion ifosfamide, administered by portable infusion pumps, is feasible in an ambulatory regimen, with acceptable non-haematological toxicity and good patient compliance.