[Mitoxantrone for the treatment of Japanese patients with multiple sclerosis].

We retrospectively evaluated the benefits of mitoxantrone (MITX) treatment in Japanese patients with multiple sclerosis (MS) with more than 3 relapses per year or a deterioration of more than one Expanded Disability Status Scale (EDSS) of Kurtzke score per year despite having IFN beta 1b therapy. Monthly intravenous injections of MITX, 10-12 mg/m2, for 3 months were followed by an additional treatment every 3 months. Nine patients (6 women, 3 men) with a mean age of 39 years, a mean disease duration of 3.9 years, and a mean EDSS score of 6.7 were studied. Seven patients had long spinal cord lesions (LCL-MS). Most patients tolerated the treatment, although 2 patients stopped MITX therapy after 3 injections because of severe appetite loss. The 7 patients who continued MITX therapy for more than 3 times significantly decreased their relapse rate and EDSS deterioration. The average relapse count in the year preceding initiation of MITX therapy was 4.3 (range: 3-6)/year, EDSS score increased by 2.7 (range: 1-7)/year. The average relapse count was 2.3 (range: 0-4)/year from 0 to 6 months after MITX therapy (p = 0.114), and 1.1 (range: 0-4)/year from 7 to 12 months (p = 0.285). The average EDSS deterioration was -0.4 (range -2-1) from 0 to 6 months after MITX therapy (p = 0.018), and there was no deterioration from 7 to 12 months. Most patients received granulocyte colony stimulating factor because of leukocytopenia caused by MITX. No patients showed any decrease in cardiac ejection fraction during this observation period. For Japanese MS patients, MITX therapy was very effective to suppress relapses without incurring severe adverse events.