A controlled study of intravenous immunoglobulin combined with prednisone in the treatment of IBM

Objective: To investigate whether the combination of intravenous immunoglob ulin (IVIg) with prednisone improves muscle strength and alters endomysial inflammation in patients with sporadic inclusion body myositis (s-IBM). Bac kground: In a previous controlled trial in s-IBM, Mg did not significantly improve strength in spite of modest benefits in some muscle groups. The pos sibility that prednisone may have a synergistic effect with Mg prompted ano ther controlled trial. Methods: Thirty-six patients with biopsy-proven IBM were randomized to receive IVIg or placebo monthly for 3 months. Before inf usions, all patients were started on high-dose prednisone for 3 months. Pri mary outcome measures were differences in the 1) Quantitative Muscle Streng th (QMT) testing; and 2) modified Medical Research Council (MRC) scores, be tween the patients randomized to IVIg + prednisone compared with those rand omized to placebo + prednisone. Repeated open muscle biopsies were performe d at random in 24 patients to determine changes in the number of autoinvasi ve T cells and necrotic muscle fibers. Results: Nineteen patients were rand omized to IVIg + prednisone and 17 to placebo + prednisone. No significant change was noted in muscle strength, assessed by QMT and MRC, from baseline to the 2nd, 3rd, or 4th month after treatment between the two groups. The number of necrotic fibers was reduced in the IVIg randomized group (p < 0.0 1), and the mean number of CD2+ cells was significantly decreased in both g roups (p < 0.0001), denoting a steroid effect. Conclusion: IVIg combined wi th prednisone for a 3-month period was not effective in IBM. Endomysial inf lammation was significantly reduced after treatment, but the reduction was not of clinical significance.