Comparison of the effectiveness of ocrelizumab vs interferons, fingolimod and natalizumab on relapses in relapsing-remitting multiple sclerosis.

Introduction: Ocrelizumab, a monoclonal antibody targeted against CD20+ B cells, has become a popular treatment for relapsing-remitting multiple sclerosis (MS). The effectiveness of ocrelizumab compared to other treatments is however unknown. Aim(s): To compare the effectiveness of ocrelizumab with interferon-beta, fingolimod and natalizumab in relapsing-remitting MS. Method(s): Using the MSBase registry, we identified patients with relapsing-remitting MS treated for >=6 months with ocrelizumab, interferon- beta (interferon beta-1a, interferon beta-1b subcutaneous or interferon beta-1b intramuscular), fingolimod or natalizumab. All patients required >12-month pre-treatment follow up and the minimum dataset. Patients with comparable baseline characteristics were matched with propensity score on age, sex, MS duration, EDSS, prior relapse rate, prior therapy, disease activity, MRI lesion burden (missing values imputed), reason for discontinuation of preceding therapy (imputed) and country. Annualised rate of relapses (ARR) and cumulative hazard of relapses were compared in pairwise-censored groups. Result(s): 106 patients treated with ocrelizumab were matched with 209 patients on interferon therapies with a mean age of 39 years, 0.8 relapses per year and mean EDSS of 2.4-2.5. Over a pairwise-censored mean follow up of 1.3 years, ocrelizumab was associated with lower relapse rates (ARR 0.08 vs 0.27, p<0.001) and lower risk of relapse (HR 0.30, 95%CI 0.15-0.57) than interferon-beta. 297 patients treated with ocrelizumab were matched with 811 fingolimod-treated patients with a mean age of 41 years, 0.6 relapses per year and mean EDSS of 2.7-2.8. Over a pairwisecensored mean follow up of 1.5 years, ocrelizumab was associated with lower relapse rates (ARR 0.03 vs 0.14, p<0.001) and lower risk of relapse than fingolimod (HR 0.21, 0.13-0.32). 262 ocrelizumab- treated patients were matched with 343 natalizumab treated patients with a mean age of 39 years, 0.8 relapses per year