MITOXANTRONE-INDUCED CARDIOTOXICITY IN PATIENTS WITH MULTIPLE SCLEROSIS

Background: There are few treatment options for patients with secondary progressive and worsening relapsing-remitting multiple sclerosis. Mitoxantrone is an antineoplastic drug, recently approved for treatment of multiple sclerosis. Mitoxantrone is, however, associated with doserelated cardiotoxicity, which limits its use. Objective: To investigate the possible cardiotoxicity of mitoxantrone in multiple sclerosis. Methods: We studied 96 patients with worsening relapsing-remitting or secondary progressive multiple sclerosis, to evaluate cardiotoxicity within one year of mitoxantrone therapy. This study was performed in the Multiple Sclerosis Clinic of Isfahan University of Medical Sciences from October 2003 through October 2004. Analysis of mitoxantrone therapy (12 mg/m2), in terms of cardiac toxicity, was conducted on patients who received at least 4 doses. Cardiac assessment was carried out every 6 months with electrocardiogram, as well as a spectral and color-flow Doppler echocardiographic examination at the time of enrollment and 6 and 12 months later. Results: Ninety-six patients were assessed over 12 months. There was no evidence of clinically-significant cardiac dysfunction. Three patients had a left ventricular ejection fraction of <10% of the base-line value and three had <50%. Conclusion: Mitoxantrone (12 mg/m2) is effective and generally well tolerated by patients with worsening relapsing-remitting and secondary progressive multiple sclerosis. Our findings suggest that the risk for developing cardiotoxicity is low in patients with multiple sclerosis within one year of the treatment with mitoxantrone.