How effective is intravenous immunoglobulin for the treatment of relapsing-remitting multiple sclerosis?

Intravenous immunoglobulin (IVIg) has been extensively used to treat humoral immunodeficiency states and various immune-mediated conditions. Several studies indicate that the benefits of IVIg with respect to relapses and MRI lesion activity compare favorably with those of interferon beta and glatiramer acetate in relapsing-remitting multiple sclerosis (RRMS) or clinically isolated syndromes. Fazekas et al. recently reported the results of a multinational, randomized, double-blind, placebo-controlled phase II trial of a new preparation of IVIg in 127 participants with RRMS. No significant benefit was demonstrated for IVIg compared with placebo for the primary end point (proportion of relapse-free participants), the main secondary end point (cumulative number of unique newly active brain MRI lesions), or a number of clinical and MRI tertiary end points. Neither the previous positive studies nor the negative results reported by Fazekas et al. can be considered to be definitive, and the utility of IVIg in RRMS remains uncertain at present.