Preliminary findings from the ETOMS (early treatment of multiple sclerosis) trial conducted in Europe showed that the drug reduced patients' loss of brain tissue compared with individuals given placebo. Results are published in the current issue of The Lancet. Massimo Filippi of Ospedale San Raffaele, Milan, Italy, led the research team.

Less Brain Tissue Loss

Around a third (31%) of 131 patients given interferon beta and just under half (47%) of 132 patients given placebo converted to clinically definite multiple sclerosis after two years follow up.

The degree of brain-tissue loss assessed by MRI scans was greater among patients given placebo (1.68% loss over the two-year period) compared with individuals given beta interferon (1.18% tissue loss).

"This study has confirmed in a large cohort of patients at the earliest clinical stage of multiple sclerosis that brain parenchymal loss takes place rapidly," said Dr. Filippi, "and has shown that 22 mg interferon beta-1a, given subcutaneously once weekly, can alter this process significantly. Whether higher or more frequent doses would enhance or reduce this effect remains untested."

Long-Term Effects Uncertain

It may be premature to conclude that a beneficial effect of interferon beta (or any other treatment) on global brain atrophy itself will produce a long-term reduction in disability, cautions David Miller of the Institute of Neurology, London, UK, in an accompanying commentary.

Still, "the report by Filippi and colleagues is encouraging and commends investigators to include brain atrophy as an outcome measure in future trials of potential disease-modifying treatments in multiple sclerosis," says Miller.