Comparative effectiveness of natalizumab and antiCD20 monoclonal antibodies in relapsing-remitting multiple sclerosis: a real-world propensity-score matched study

Background Head-to-head randomised trials or real-world studies comparing the safety and efficacy of natalizumab and anti-CD20 monoclonal antibodies are limited. This study aimed to compare the effectiveness and safety of natalizumab versus ocrelizumab/rituximab in a real-world cohort of relapsing-remitting multiple sclerosis (RRMS) patients using data from the Middle East and North Africa Committee for the Treatment and Research in Multiple Sclerosis (MENACTRIMS) registry. Methods This registry-based, retrospective, multicentre study was carried out in seven Middle Eastern countries by analysing data from the MENACTRIMS registry. All adults RRMS patients treated with natalizumab, rituximab or ocrelizumab and maintained on treatment for at least 12 months were included. Patients were matched using propensity scores. Primary outcomes were annualised relapse rate (ARR), confirmed disability progression and improvement and MRI activity. Results A total of 1954 patients met the inclusion criteria, with 1277 receiving anti-CD20 therapy (768 on rituximab and 509 on ocrelizumab) and 677 natalizumab. Natalizumab significantly reduced ARR compared with anti-CD20 therapies (0.062 vs 0.092, p=0.001). Confirmed disability progression rates, MRI outcomes and no evidence of disease activity (NEDA-3) were similar between the two groups. However, natalizumab demonstrated higher rates of disability improvement compared with anti-CD20 therapies (9.3% vs 5.5%, p=0.03). Adverse events were more frequent in the anti-CD20 group (36.4% vs 27.5% for natalizumab, p=0.001). Conclusion In this large, real-world cohort, natalizumab was associated with lower ARR, greater likelihood of disability improvement, lesser adverse events, but lower persistence compared with anti-CD20 therapies. These findings provide valuable insights into the comparative efficacy and safety of these RRMS therapies, aiding clinicians in personalised treatment decisions.