A PROSPECTIVE RANDOMIZED EVALUATION OF 3 SCHEDULES OF MESNA ADMINISTRATION IN PATIENTS RECEIVING AN IFOSFAMIDE-CONTAINING CHEMOTHERAPY REGIMEN - SUSTAINED EFFICIENCY AND SIMPLIFIED ADMINISTRATION

Chemotherapy with oxazaphosphorines, such as ifosfamide, is often limi ted by unacceptable urotoxicity. Without uroprotection hemorrhagic cys titis becomes dose-limiting. Mesna, a thiol compound, is a drug able t o bind the toxic metabolites, forming nontoxic compounds in the urine. A total of 122 patients were enrolled in this study and 228 chemother apy cycles with an ifosfamide-containing regimen were performed (225 e valuable). Mesna was given at the same total dose as the ifosfamide in all arms. On arm A, mesna was given i. v. in equal doses 15 min befor e and 4 h and 8 h following the ifosfamide dose. On arm B, mesna was g iven in three equivalent doses 15 min before (i.v.) and 4 h (i.v.) and 8 h (p.o., double dose) following ifosfamide. On arm C, mesna was giv en i.v. in two equal doses given 15 min before and 4 h following, The incidence of urotoxicity was very low (lower than 15%) in the three ar ms, 0% in A, 1.36% in B and 2.70% in C, All three arms were equally ef ficient. Schedule C was considered superior to the others, since it wa s equally effective, simpler and more convenient.