Treatment of inclusion-body myositis with high-dose intravenous immunoglobulin.

We report the treatment of four patients with inclusion-body myositis (IBM) and severe slowly progressive weakness using high-dose intravenous immunoglobulin (IVIg). After two monthly infusions, the strength of the proximal and less atrophic muscle groups improved or normalized in three of the four patients. The improvement lasted from 2 to 4 months. Intravenous immunoglobulin is the first treatment modality to improve the strength of some muscles in patients with this disabling inflammatory myopathy. In view of the high cost of IVIg, the unexpected but encouraging results from this pilot study warrant a controlled trial.