New interferon drug shows positive results.

Ares-Serono has completed a placebo-controlled clinical trial of Rebif (interferon beta 1a) for relapsing-remitting MS. This was a large trial, with 560 people participating in 22 MS treatment centers in Europe, Canada, and Australia. It measured the effects of two different doses of Rebif, which were injected subcutaneously (under the skin) 3 times a week for 2 years.

Positive benefit profile

Like the other interferons now marketed for MS, this drug reduced the rate of relapses (or attacks). Depending on the dose, the reduction in relapse rate was 28.9% or 32.4%. Rebif also slowed the progression of disability and significantly reduced the number of lesions in the brain seen by MRI.

Most of the volunteers taking Rebif had the now familiar flu-like reactions, which lessened with continued use. Some had injection-site inflammation. Depending on the dose, neutralizing antibodies developed in 15% to 23% of people on the drug.

Awaiting approval

The manufacturer, Ares-Serono, a Swiss pharmaceutical company, is in discussions with the FDA regarding registration in the U.S. and is awaiting approval in Europe and Canada. For more information on Rebif, contact Ares-Serono's U.S. headquarters at 1-800-283-8088.