The development of the immunomodulatory, disease-modifying therapies (DMT) represents a major advance for the treatment of multiple sclerosis (MS). To date, immunomodulatory agents approved for the treatment of MS in the United States include two forms of recombinant interferon-beta (IFN-beta-1a [Avonex, Rebif] and IFN-beta-1b [Betaseron]) and synthetic glatiramer acetate [Copaxone].