Efficacy and safety of Ocrelizumab in comparison to placebo for multiple sclerosis: A systematic review and meta-analysis

Abstract Objective: This meta-analysis focuses on the combined results of all available trails and cohort studies reporting efficacy and safety of ocrelizumab. Introduction: Multiple Sclerosis is a chronic, immune-mediated neurodegenerative disorder characterized by demyelination and inflammation of the CNS. Multiple sclerosis is characterized by two pathognomonic signs i.e. inflammation and demyelination and gliosis and neurodegeneration. Methods: To identify relevant literature, an unrestricted electronic search was executed across PubMed, the Cochrane Database of Systematic Reviews, and ClinicalTrials.gov. This search covered all available records until February 20, 2025. Risk of bias assessment was done separately for observational studies and RCTs using Newcastle–Ottawa Scale (NOS) and Cochrane Risk of Bias tool (RoB 2.0) respectively. Data analysis was done using Review Manager (version 5.4.1). Results: This meta-analysis included 24 studies (5 RCTs and 19 observational studies). Ocrelizumab showed significant reduction in annualized relapse rate (ARR) with a mean difference of -0.03 [95% CI: -0.05, -0.01]. This indicates a small but statistically significant reduction in ARR. Results also showed that Ocrelizumab is associated with an increased likelihood of achieving NEDA, with a statistically significant overall risk ratio of 1.24 [95% CI: 1.05, 1.47]. Ocrelizumab was also associated with reduction in relapses compared to placebo, with a combined risk ratio (RR) of 0.54 [95% CI: 0.33, 0.89]. Conclusion: Ocrelizumab demonstrates robust efficacy in reducing relapses and enhancing NEDA, particularly in controlled trial settings, but does not show significant benefits in preventing disability progression over short-term follow-up. Its safety profile is comparable to placebo, though long-term monitoring is essential.