Patients with multiple sclerosis (MS) may change immunomodulatory therapies if efficacy is considered inadequate or if adverse drug reactions occur. Identifying potential candidates for therapy adjustment is an important aspect of treatment optimization. This study aimed to evaluate the safety and efficacy of interferon beta-1a (IFNβ-1a), 44 μg subcutaneously (SC) three times weekly, in patients with relapsing MS following a change from another long-term therapy and to identify potential candidates for therapy adjustment. Patients were followed for 12 months. Candidates for therapy adjustment were identified using a three-scale model of treatment efficacy (relapses, disability progression, and magnetic resonance imaging). For 76.4% of patients, insufficient efficacy of the previous therapy was the main reason for changing to IFNβ-1a 44 μg. At baseline, 70.6% of patients fulfilled the criteria for recommendation for therapy adjustment; after 12 months on IFNβ-1a 44 μg, this percentage decreased to 16.6%. The incidence of adverse events (AEs) decreased between week 4 (40.6% of patients) and month 12 (12.8%). Influenza-like symptoms were the most common AE, occurring in 28.3% of patients. This study supports IFNβ-1a, 44 μg SC three times weekly, as a therapeutic option for patients in need of therapy adjustment.
Long-term disability progression of pediatric-onset multiple sclerosis