Future immunotherapies in multiple sclerosis.

Immunotherapy of multiple sclerosis (MS) will continue to benefit from an increasing understanding of this disease. This knowledge results in newly defined targets for novel therapies. In this article the development of future immunotherapies will be discussed by classifying the approaches into three main types: (1) antigen-specific therapies; (2) agents with a defined target in pathogenic steps of the MS lesion; and (3) therapies with broad immunomodulatory activity. Success in developing new immunotherapies depends on understanding the underlying complexity and heterogeneity of the disease. The current practice of employing a single therapy across a heterogeneous group of MS patients is in part a likely reason for their modest efficacy. The mechanism of action of a single agent may target the appropriate defect in one individual but not others. The therapy of MS in the future will most likely use a combination of agents that are directed at the underlying disease state and stage in the individual patient.