HealthDay News — After 15 years of follow-up, patients with relapsing-remitting multiple sclerosis (RRMS) who display disease activity despite treatment with interferon (IFN)β-1a tend to have unfavorable long-term outcomes, study results indicate.

Among patients treated with IFNβ-1a, persistent disease activity was associated with an 8.96-fold higher risk of gadolinium-enhancing lesions (P<0.001), a 4.44-fold higher risk of relapse (P= 0.010), and a 2.90-fold higher risk of new T2 lesions (P= 0.080), Robert A. Bermel, MD, of the Cleveland Clinic, and colleagues reported in Annals of Neurology.

“Particular attention should be paid to gadolinium-enhancing lesions on IFNβ therapy, as their presence strongly correlates with severe disability 15 years later,” they wrote.

Continue Reading

The researchers conducted a multicenter, observational, 15-year follow-up study involving 136 patients with RRMS, who had initially been treated with either intramuscular IFNβ-1a or placebo, to identify early predictors of long-term outcomes.

The proportion of patients experiencing early disease activity was lower in patients on intramuscular IFNβ-1a than placebo for all disease activity markers (range, 23.5%–29.0% vs. 41.0–45.5%), the researchers found.

Conversely, early disease activity in placebo-treated patients was not associated with long-term outcomes (OR range=1.53–2.62; P=0.069–0.408).

“The results provide rationale for monitoring IFNβ treated patients with magnetic resonance imaging, and for changing therapy in patients with active disease,” the researchers wrote.


  1. Bermel RA et al. Ann Neurol. 2013; 73: 95–103.