MAGNIMS score predicts long-term clinical disease activity-free status and confirmed disability progression in patients treated with subcutaneous interferon beta-1a

Background: Subcutaneous (sc) interferon (IFN) β-1a reduces relapse rates and delays disability progression in patients with MS. We examined the association of the year 1 Magnetic Resonance Imaging in MS (MAGNIMS) score with long-term clinical disease activity (CDA) -free status and confirmed disability progression in patients treated with sc IFN β-1a in PRISMS. Methods: Patients treated with sc IFN β-1a three-times-weekly (22 or 44 μg; pooled data) were classified by MAGNIMS score (0, n = 129; 1, n = 108; 2, n = 130) at year 1. Hazard ratios (HR; 95% confidence intervals [CI]) for risk of CDA and confirmed Expanded Disability Status Score (EDSS) progression were calculated by MAGNIMS score for up to 15 years of follow-up. Results: The risk of CDA was higher with a year 1 MAGNIMS score of 1 versus 0 (HR 1.82 [1.38–2.41]), 2 versus 0 (2.63 [2.01–3.45]) and 2 versus 1 (1.45 [1.11–1.89], all p < 0.0001). The same outcome was observed with the risk of confirmed EDSS progression (1 versus 0: 1.93 [1.23–3.02]; 2 versus 0: 2.95 [1.95–4.46]; 2 versus 1: 1.53 [1.05–2.23]; all p < 0.0001). Conclusion: In PRISMS, MAGNIMS score at Year 1 predicted risk of CDA and confirmed disability progression in sc IFN β-1a-treated patients over up to 15 years. PRISMS-15 clinicaltrial.gov identifier: NCT01034644