Study Finds IVIG Effective for Treating Dermatomyositis

A study evaluating intravenous immune globulin (IVIG) for the treatment of dermatomyositis has found it significantly improved patient outcomes.

In the 16-week study involving adults with dermatomyositis, 95 patients were assigned in a 1:1 ratio to receive IVIG at a dose of 2.0 grams per kilogram of body weight or placebo every four weeks for 16 weeks. The patients who received placebo and those without confirmed clinical deterioration while receiving IVIG could enter an open-label extension phase for another 24 weeks. The primary end point was a response defined as a Total Improvement Score (TIS) of at least 20 (indicating at least minimal improvement) at week 16 and no confirmed deterioration up to week 16. The TIS is a weighted composite score reflecting the change in a core set of six measures of myositis activity over time; scores range from 0 to 100, with higher scores indicating greater improvement. Key secondary end points included at least moderate improvement (TIS ≥40) and major improvement (TIS ≥60), and change in score on the Cutaneous Dermatomyositis Disease Area and Severity Index.

Forty-seven patients were assigned to the IVIG group and 48 to the placebo group. At 16 weeks, 79 percent of the patients in the IVIG group (37 of 47) and 44 percent of those in the placebo group (21 of 48) had a TIS of at least 20. The results with respect to the secondary end points, including at least moderate improvement and major improvement, were generally in the same direction as the results of the primary end-point analysis, except for the change in creatine kinase level (an individual core measure of the TIS), which did not differ meaningfully between the two groups. Over 40 weeks, 282 treatment-related adverse events occurred in the IVIG group, including headache (42 percent of patients), pyrexia (19 percent) and nausea (16 percent). A total of nine serious adverse events that were considered to be related to IVIG occurred, including six thromboembolic events.