Rapid benefits of a new formulation of subcutaneous interferon beta-1a in relapsing—remitting multiple sclerosis

This study evaluated the efficacy of a new formulation of subcutaneous (sc) interferon (IFN)-beta1a in relapsing-remitting multiple sclerosis (RRMS). Patients (n = 180) were randomized (2 : 1) to IFN-beta1a or placebo for 16 weeks; all patients then received IFN-beta1a for 24 weeks. Monthly brain MRI was performed. At week 16, the mean number of combined unique active (CUA) lesions was lower with IFN-beta1a than with placebo (p < 0.001; 69% fewer lesions). The mean cumulative number of CUA lesions was already lower with IFN-beta1a by week 4 (post hoc analysis; p = 0.015). The new formulation of sc IFN-beta1a has rapid beneficial effects on MRI outcomes in RRMS.