Ocrevus (ocrelizumab) is not chemotherapy, it is a targeted treatment that works by binding to a protein called CD20 that is present on the surface of B-lymphocytes, which are a type of white blood cell. When Ocrevus binds to this protein, it causes B-cells to self-destruct or disintegrate.

Ocrevus may also be called a biologic or a monoclonal antibody.

Ocrevus is FDA approved for the treatment of relapsing forms of multiple sclerosis (MS) and primary progressive MS, in adults. How Ocrevus exerts its effects in MS is unknown, but it is presumed to be due to self-destruction or disintegration of immature and mature B-lymphocytes, which are associated with inflammation and myelin damage.

Research has shown that Ocrevus is effective at reducing the number of relapses per year in people with MS, increasing the percentage of people who remain relapse-free, and reducing the rate of disability progression.