Ocrevus (ocrelizumab) is a medication used to treat multiple sclerosis. It targets CD20 protein found on the surface of certain immune cells, reducing attacks, and progression of the disease. It is administered as an intravenous infusion every 6 months and has been shown to significantly reduce relapse rates in people with relapsing-remitting MS, slow disability progression in those with relapsing and progressive MS. It is being investigated for potential use in other autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus.