Early Interferon Beta-1b Treatment Thwarts MS Progression: Presented at AAN

Using interferon beta-1b (Betaseron) therapy in patients with the first clinical symptoms of MS (MS) significantly postpones the development of clinically definite MS, according to the results of the Betaseron in Newly Emerging MS for Initial Treatment (BENEFIT) trial. 

Principal investigator

Mark S. Freedman, MD,

director, MS Research Unit,

University of Ottawa,

Ottawa, Canada,

presented the BENEFIT data at the Annual Meeting of the American Academy of Neurology (AAN).

"While doctors typically wait years after a first demyelinating event to start treatment, our study provides a strong rationale for the use of early interferon beta-1b therapy," Dr.  Freedman said.

Dr.  Freedman and colleagues from Canada, Europe, and Israel, randomized 487 patients with a first clinically demyelinating event suggestive of MS and typical magnetic resonance imaging (MRI) findings in a 5:3 ratio to treatment to receive either 250 mcg interferon beta-1b given every other day or placebo as a subcutaneous injection.

Treatment continued for up to 24 months, unless patients experienced a second attack and were diagnosed with clinically definite MS.

Two co-primary endpoints were defined as follows:

1) the time to clinically definite MS, based on a second clinical demyelinating event or an Expanded Disability Status Scale (EDSS) progression of at least 1.5 points, and

2) the time to MS according to McDonald Criteria.

The 2 treatment groups were balanced with regard to demographic and clinical characteristics.  The mean age of the study population was 30.7 years.

After 2 years, 28% of the interferon beta-1b group had developed clinically definite MS versus 45% of placebo-treated patients (P <.  0001).

Using McDonald criteria, 69% of the interferon beta 1-b group were determined to have developed MS versus 85% of the placebo cohort (P <.  00001).

Interferon beta-1b prolonged the time to clinically definite MS by 363 days.

The treatment effect was most pronounced in patients with clinically less disseminated disease, lower lesion loads, or no enhancing lesions on MRI.

Dr.  Freedman said that, as part of the BENEFIT trial, patients will be followed prospectively for up to 5 years to verify the benefit of early treatment on long-term outcome.

This study was supported by Schering AG.