Extended treatment with fingolimod for relapsing multiple sclerosis: the 14-year LONGTERMS study results

Background: Multiple sclerosis (MS) is a chronic disease that may require decades of ongoing treatment. Therefore, the long-term safety and efficacy of disease-modifying therapies is an important consideration. Methods: The LONGTERMS study evaluated the safety and efficacy of fingolimod in patients with relapsing MS (RMS) with up to 14 years of exposure. This phase IIIb, open-label extension study included patients aged > 18 years with confirmed RMS diagnosis who completed previous phase II/III/IIIb core/extension studies of fingolimod. Patients received fingolimod 0.5 mg orally once daily; safety and efficacy (clinical and magnetic resonance imaging) were the main outcomes. Results: Of 4086 patients from the core studies who entered LONGTERMS, 3480 (85.2%) completed the study. The median age (range) was 38 (17-65) years and median fingolimod exposure was 944.5 (range 75-4777) days. Overall, 85.5% of patients experienced at least one adverse event (AE); most common AEs (> 10%) were viral upper respiratory tract infection (17.3%), headache (13.3%), hypertension (11.0%) and lymphopenia (10.7%). Among patients with serious AEs (12.6%), basal cell carcinoma and MS relapse (0.9% each) were most frequently reported. The aggregate annualized relapse rate decreased from 0.22 (in years 0-2) to 0.17 (years 0-10); 45.5% of patients remained relapse free after 10 years. At year 10, 63.2% of patients were free from 6-month confirmed disability worsening. Conclusion: This long-term observational study of patients treated for up to 14 years with fingolimod confirmed its established safety profile with no new safety concerns. Patients with RMS receiving fingolimod had sustained low levels of disease activity and progression.