Early use of interferon beta patients with multiple sclerosis.

In recent years, major advances have been made in the management of multiple sclerosis (MS) in the form of new disease-modifying therapies, the most widely used of which is interferon (IFN) beta. A growing body of evidence indicates that the beneficial effects of IFN beta are maximised if treatment is started as soon as possible after the diagnosis of MS, and if patients are given the highest possible dose. The argument in favour of early treatment is based primarily on the finding that the inflammation of the central nervous system characteristic of MS leads to irreversible axonal destruction starting very early in the course of the disease. Evidence that IFN beta should be given at high doses comes from preclinical and clinical studies showing that the effects of this drug are strongly dose-dependent. Three formulations of IFN beta are currently available for the treatment of MS: subcutaneous (s.c.) IFN beta-1a, intramuscular (i.m.) IFN beta-1a and s.c. IFN beta-1b. All are well tolerated, although IFN beta-1a appears to be less immunogenic than IFN beta-1b. IFN beta-1a, in s.c. formulation, has advantages over the other formulations in terms of convenience, and is approved for use at higher doses than i.m. IFN beta-1a.