Preventing multiple sclerosis?

A common feature of organ-specific autoimmune disorders is a broad disease spectrum, which ranges from self-limited acute illnesses to relapsing or more chronic and fatal forms. The variation is less in disorders in which a threshold effect must be exceeded to result in symptoms, as in juvenile diabetes. However, a wide spectrum occurs in most autoimmune disorders, including uveitis, non-infectious arthritis, as well as in optic neuritis and other monosymptomatic demyelinating syndromes. In the last group it is now possible to identify with some accuracy those patients at highest risk of recurrence of lesions elsewhere in the nervous system. Well-validated markers of recurrence include the presence of additional lesions on magnetic-resonance imaging, the presence of the MHC allele DRB 1501, and oligoclonal bands in the cerebrospinal fluid. 1,2 When the well-used definitions of dissemination in time and space are satisfied (perhaps in 50–60% of cases), 3 the demyelinating syndrome is called relapsing-remitting multiple sclerosis. Since there is now overwhelming evidence that type 1 interferons reduce exacerbation rates in multiple sclerosis by a third, 4–6 it was inevitable that their potential would be evaluated in patients with their first attack. Appropriately they have been first tested in those with a high risk of new lesions. The driving hypothesis might have been that disease at the first attack is more susceptible to the effects of interferon. Two recent studies, CHAMPS (Controlled High-Risk Subjects Avonex Multiple Sclerosis Prevention Study) 7 and ETOMS (Early Treatment of Multiple Sclerosis), which is published in today's Lancet, have each shown that the time to the development of a second clinical lesion is prolonged by type 1 interferons. With relapse suppression of the degree seen in trials of patients with multiple sclerosis (ie, about a third), the prolongation of time to relapse in CHAMPS and ETOMS was to be expected. However, have the findings any implications for everyday clinical practice? Both studies were stopped far too soon to enable definitive answers to the question of treatment value. In neither study was the delay in time to the second exacerbation greater than that seen in the trial of intravenous solumedrol given to patients with optic neuritis around the time of the initial exacerbation. 8 Since two large (unpublished) studies in secondary progressive multiple sclerosis have been negative, the results of CHAMPS and ETOMS may be taken to boost the prospects of interferon therapy. Despite lack of evidence, the notion …