ABSTRACT: We sought to retrospectively review a single-center experience using intravenous immunoglobulin (IVIG) for the treatment of refractory, active diffuse cutaneous systemic sclerosis (dcSSc).The mean modified Rodnan Skin score (mRSS) at baseline was compared to the mRSS at 6, 12, 18, and 24 months post-IVIG initiation by the paired Student t test. Changes in mRSS at 6 and 12 months were also compared to data from historical controls of 3 large, negative, multicenter, randomized clinical trials of other medications [D-penicillamine (D-pen), recombinant human relaxin (relaxin), and oral bovine type I collagen (collagen)] and to patients treated with mycophenolate mofetil (MMF) alone using the Student t test.Thirty patients were treated with adjunctive IVIG (2 g/kg/mo) for refractory, active dcSSc. The mean baseline mRSS of our cohort was 29.6 ± 7.2, and this significantly decreased to 24.1 ± 9.6 (n = 29, p = 0.0011) at 6 months, 22.5 ± 10.0 (n = 25, p = 0.0001) at 12 months, 20.6 ± 11.8 (n = 23, p = 0.0001) at 18 months, and 15.3 ± 6.4 (n = 15, p < 0.0001) at 24 months. The mean change in mRSS at 6 months was not significantly different in the IVIG group (-5.3 ± 7.9) compared to the relaxin trial (-4.8 ± 6.99, p = 0.74) or MMF group (-3.4 ± 7.4, p = 0.26); however, at 12 months, the mean change in mRSS was significantly better in the IVIG group (-8 ± 8.3) than in the D-pen (-2.47 ± 8.6, p = 0.005) and collagen (-3.4 ± 7.12, p = 0.005) groups, and was comparable to the group of primary MMF responders (-7.1 ± 9, p = 0.67).Our observational study suggests that IVIG may be an effective adjunctive therapy for active dcSSc in patients failing other therapies.