Interaction between cisplatin and mesna in mice

The uroprotectant thiol mesna was found to protect adult CD-1 mice from high-dose cisplatin lethality. Mesna doses of 50 mg/kg were given with cisplatin, or 5 min after cisplatin (25 or 30 mg/kg) and acute survival was increased in non-tumor-bearing mice. In contrast, mesna mixed directly with cisplatin significantly reduced cisplatin antitumor effects in DBA/2J mice given 10⁶ P-388 leukemia i.p. Mesna administered i.p. 5 min after cisplatin (6,8 or 10 mg/kg) did not reduce cisplatins' antitumor efficacy in this same tumor model. Mesna appears to inactivate cisplatin directly in vitro but possibly not in vivo if separate injections are used.