Current and future role of interferon beta in the therapy of multiple sclerosis.

Interferon beta was the first specific disease-modifying therapy licensed for multiple sclerosis (MS) and in its many forms remains the most commonly prescribed agent worldwide. It, however, has a modest effect in reducing relapse rates, magnetic resonance imaging activity, and disability, and many patients are unable to tolerate it because of the associated side effects or mode of administration. With the licensing of glatiramer acetate, natalizumab and mitoxantrone as disease-modifying therapies for MS alternative options are available to people with MS. Many exciting new therapies are also in the pipeline, namely, the monoclonal antibodies alemtuzumab, rituximab, and daclizumab and the promising oral agents BG00012, cladribine, fingolimod, laquinimod, and teriflunomide. In this article we review the immunopathology of MS and the proposed mechanisms of action of currently available and anticipated treatments. We also review the efficacy of each drug, use of combination therapy strategies, and the potential role of the interferon beta preparations in the future.