Early evidence of disease activity during fingolimod predicts medium-term inefficacy in relapsing-remitting multiple sclerosis

Background: Fingolimod (FTY) is an effective second-line drug for relapsing-remitting multiple sclerosis, with ~50% patients showing no evidence of disease activity (NEDA) after 2 years. Nonetheless, the early identification of non-responders is extremely important, to promptly address them to more aggressive drugs. Objectives: This cohort study evaluates FTY medium-term effectiveness, searching for early markers of treatment failure. Patients and methods: Three hundred eighty patients starting FTY were enrolled and classified according to NEDA and time to first relapse criteria at 4-year follow-up. Logistic and Cox regression analyses were applied to identify early predictors of non-response. Results: At 4 years, 65.6% of patients were free from relapses and 35.4% had NEDA. Female gender was associated with a higher risk of non-response. Moreover, evidence of clinical and/or magnetic resonance imaging (MRI) activity during the first year of treatment was highly predictive of disease activity in the follow-up: the positive predictive value for non-response was 0.74 for the presence of ⩾1 relapse, 0.73 for the presence of ⩾1 active MRI lesion, and 0.83 for the presence of both clinical and MRI activity. Conclusions: FTY effectiveness persists at medium-term follow-up; a close monitoring during the first year of treatment is warranted to early identify non-responders requiring treatment optimization.