ABSTRACT
Thirty-five years after the first description of interferons (IFNs) as antiviral agents by Isaacs and Lindenmann in 19571, and 12 years after the first therapeutic trial indicating a beneficial effect of interferon beta (IFN-β) in multiple sclerosis (MS) was reported by Jacobs et al.2-4, IFN-β-1b (Betaseron®, Betaferon®) was approved for the treatment of MS in 19935,6. Since then, two additional IFN-β products, IFN-β-1a by intramuscular injection (IFN-β-1a (IM), Avonex®) and IFN-β-1a by subcutaneous injection (IFNβ-1a (SC), Rebif®), have been approved to treat relapsing-remitting MS (RRMS). IFN-β has also been approved in some countries to treat secondary progressive MS (SPMS). For more than 10 years IFN-β has played a key role in the management of MS patients. In this chapter, the mode of action of IFN-β in MS, evidence supporting efficacy on clinical and laboratory measures and current knowledge about the emerging differential indications are reviewed.
