ocrelizumab
ocrelizumab
Overview
Ocrelizumab is a humanized monoclonal antibody that targets CD20 on B cells and is used as a high-efficacy immunotherapy in multiple sclerosis (MS). By depleting CD20-expressing B lymphocytes, it modulates the immune processes that contribute to inflammatory demyelination and disability accumulation in MS. It is approved for relapsing forms of MS and primary progressive MS (PPMS), making it one of the major disease-modifying therapies in contemporary MS care.
Biologically, ocrelizumab is part of the anti-CD20 class of B-cell–depleting therapies. In clinical practice and research, it is often discussed alongside other MS therapies such as natalizumab (Tysabri®), particularly when comparing first-line treatment strategies for newly diagnosed people with MS. Its role has also been examined in more advanced disease settings, including PPMS and aggressive phenotypes of MS, where B-cell depletion may help stabilize disease activity.
Focus of Latest Publications
Recent publications on ocrelizumab have focused on its comparative effectiveness, dose optimization, and outcomes in broader multiple sclerosis populations. Several studies addressed the lack of head-to-head evidence for anti-CD20 therapy in relapsing multiple sclerosis, including a comparison of rituximab versus ocrelizumab in newly diagnosed relapsing disease and a real-world comparison of natalizumab versus ocrelizumab in treatment-naïve people with multiple sclerosis. The natalizumab study reported improved relapse outcomes and lower healthcare utilization with natalizumab relative to ocrelizumab, highlighting ongoing uncertainty about where ocrelizumab fits among first-line options in newly diagnosed patients.
Other recent work has examined whether higher ocrelizumab exposure improves clinical effects. Two multicentre, randomized, double-blind phase 3b trials, MUSETTE in relapsing multiple sclerosis and GAVOTTE in primary progressive multiple sclerosis, prospectively assessed a bodyweight-adjusted higher dose of ocrelizumab after prior post-hoc analyses had suggested that greater exposure was associated with more complete B-cell depletion and lower risk of confirmed disability progression. In parallel, ORATORIO-HAND evaluated ocrelizumab in primary progressive multiple sclerosis, including older patients and those with more advanced disease, with a particular emphasis on preserving hand function.
Real-world effectiveness and safety have also been studied. A nationwide study from Slovakia evaluated ocrelizumab in relapsing-onset multiple sclerosis, and another publication addressed disease reactivation after discontinuation, focusing on recurrence of disease activity, disability progression, and the uncertainty around how long treatment should continue before cessation. Together, these reports suggest continued interest in defining ocrelizumab’s comparative performance, optimal dosing, and durability of benefit across relapsing and progressive forms of multiple sclerosis.
Key Publications
- Jul Rituximab versus Ocrelizumab in Newly Diagnosed Relapsing Multiple Sclerosis. (The New England journal of medicine, 2026, PMID 42384870): "Rituximab versus Ocrelizumab in Newly Diagnosed Relapsing Multiple Sclerosis."
- Jun Natalizumab is associated with improved relapse outcomes and lower healthcare utilization versus ocrelizumab in treatment-naïve people with multiple sclerosis. (Journal of medical economics, 2026, PMID 42323726): "Natalizumab (NTZ) and ocrelizumab (OCR) are well-established therapies and commonly considered first-line for newly diagnosed people with multiple sclerosis (pwMS) in the United States."
- May Efficacy and safety of a bodyweight-adjusted higher dose of ocrelizumab in relapsing (MUSETTE) and primary progressive (GAVOTTE) multiple sclerosis: two multicentre, randomised, double-blind, parallel-group phase 3b trials. (Lancet (London, England), 2026, PMID 42208560): "Ocrelizumab is a humanised anti-CD20 monoclonal antibody approved for people with relapsing (RMS) or primary progressive multiple sclerosis (PPMS)."
- May Efficacy and safety of ocrelizumab in primary progressive multiple sclerosis, including older patients and those with more advanced disease (ORATORIO-HAND): a multicentre, double-blind, randomised, placebo-controlled, phase 3b study. (Lancet (London, England), 2026, PMID 42208561): "The ORATORIO trial showed that ocrelizumab reduced the risk of disability progression versus placebo in patients with primary progressive multiple sclerosis (PPMS)."
- Jun Effectiveness and safety of ocrelizumab in relapsing-onset multiple sclerosis: A nationwide real-world study from Slovakia. (Multiple sclerosis and related disorders, 2026, PMID 42013711): "Ocrelizumab (OCR) is a high-efficacy anti-CD20 monoclonal antibody approved for multiple sclerosis (MS) treatment."
- May Discontinuation of ocrelizumab in multiple sclerosis: reoccurrence of disease activity. (Journal of neurology, neurosurgery, and psychiatry, 2026, PMID 41558853): "The optimal strategy after discontinuation of B-cell depleting therapies like ocrelizumab in people with multiple sclerosis (pwMS) remains uncertain, particularly regarding delayed disease reactivation, disability progression and required treatment duration before cessation."