Clinical study of fk506 in patients with myasthenia gravis

Abstract

To investigate the usefulness of low‐dose FK506 for the treatment of myasthenia gravis (MG), we treated 19 patients with generalized MG in a 16‐week open clinical trial of FK506 (3–5 mg/day). At the end of the trial, total MG scores (range: 0–27 points) improved by 3 points or more in 7 of 19 patients (37%), and activities of daily living (ADL) scores (range: 0–6 points) also improved by 1 point or more in 8 of 19 patients (42%). Nine of 19 patients (47%) showed improvement in either MG or ADL scores. Significant reduction of anti‐acetylcholine receptor antibody titers and interleukin 2 production were observed at the end of this study. Minor but commonly observed side effects were an increase in neutrophil count and a decrease in lymphocyte count. No serious adverse events such as renal toxicity or diabetes mellitus were observed during the 16‐week treatment period. FK506 could safely serve as an adjunct to steroid therapy for MG at low dosage. Muscle Nerve 28: 570–574 2003