Efficacy of mesna for prevention of hemorrhagic cystitis after high-dose cyclophosphamide therapy.

For these reasons, a definitive statement about the relative efficacy of mesna for prophylaxis of cyclophosphamide-associated HC in BMT patients cannot be made. Because HC is a frequent and potentially serious complication of high-dose cyclophosphamide therapy, the implementation of some preventive measure is mandatory in all patients. Unless medically contraindicated, provision of sufficient hydration and diuresis to maintain adequate high urine flow should be a component of all prophylactic regimens. It is unclear whether the addition of mesna therapy or bladder irrigation to intravenous hydration provides greater protection. Studies indicate that mesna probably has no adverse effect on engraftment. This is consistent with its chemistry and pharmacology, as the drug is hydrophilic and activated only in the kidneys. Thus, it is inactive in the bloodstream and unable to penetrate cell membranes and interfere with the action of cyclophosphamide. Although safety issues surrounding the use of mesna for prevention of cyclophosphamide-associated HC appear to have been resolved, efficacy issues must await the completion of further well-controlled comparative trials.