By Thomas S. May
RHODES, GREECE -- June 20, 2007 -- Patients with relapsing-remitting multiple sclerosis (MS), the most common form of MS, derive greater benefit from interferon beta-1a when it is administered subcutaneously at a 44 mcg dose three times weekly than when it is given as a 30 mcg intramuscular injection once a week. This finding was announced here at the annual Meeting of the European Neurological Society (ENS), based on interim results of the Evidence of Interferon Dose-response: European North American Comparative Efficacy (EVIDENCE) trial.
"The EVIDENCE study was a head-to-head comparison of two important Interferon beta-1a products for MS, and it determined that there is a significant early and sustained benefit, both for clinical and MRI outcomes, from using a higher frequency and higher dose of interferon," said lead investigator Anthony Traboulsee, MD, clinical assistant professor, department of neurology, University of British Columbia Hospital, Vancouver, British Columbia, Canada. "The data presented here is an extension of the MRI results, specifically looking at T 2 burden of disease," Dr. Traboulsee added. "T 2 burden of disease represents the chronic accumulation of new and old MS lesions, and it was the first MRI measure approved by regulatory agencies for clinical trials."
The EVIDENCE trial compared T 2 burden of disease (BOD) between two groups of patients: subjects in one group (n=279) were given 44 mcg of Interferon beta-1a (IFN beta-1a) subcutaneously (sc) three times a week, while subjects in the other group (n=274) received 30 mcg of IFN beta-1a intramuscularly (im) once a week. The primary endpoint was percentage change in BOD over 48 weeks, and all patients with evaluable T 2 MRI scans at baseline and at week 48 were included in the analysis.
The investigators found that median percentage reduction in BOD from baseline to week 48 was greater in the 44 mcg sc treatment group than in the 30 mcg im group (–6.7 % [range –65, 431] versus –0.6 % [range –61, 197]). Median absolute reduction in BOD was also greater in the 44 mcg sc group (–189.5 mm3; range –23454, 56869) than the 30 mcg im group (–19.0 mm3; range –13337, 10161).
Based on these data, the investigators concluded that patients treated with 44 mcg of subcutaneous Interferon beta-1a three times per week had significantly greater reductions in T 2 burden of disease than those receiving 30 mcg intramuscular injections once a week. According to Dr. Traboulsee, "this study demonstrates the benefits of high dose, high frequency dosing on suppression T 2 BOD, and is consistent with previous results showing similar benefits on relapse rates."
Financial support for the EVIDENCE trial was provided by Merck Serono, the makers of Interferon beta-1a.
[Presentation title: Reduction in T2 Burden of Disease Is Greater With Interferon beta-1 a 44 mcg Administered Subcutaneously Three Times Weekly Than 30 mcg Administered Intramuscularly Once Weekly: 1-Year Analysis of the EVIDENCE Study Data. Abstract P539]
