OCREVUS (generic name Ocrelizumab) is a humanized monoclonal antibody under clinical investigation and development by the Swiss pharmaceutical company Roche as a potential treatment for people with multiple sclerosis (MS). The therapy is targeted against mature B-lymphocytes with CD20 markers on their surface, giving the drug an immunosuppressive function that might reduce the rates of immune system attacks on its own myelinated neurons, the main pathogenesis in the disease. OCREVUS is not yet an approved therapy, but it has shown promise in treating both relapsing forms of multiple sclerosis and primary progressive multiple sclerosis, a disease form with no approved treatments to date.
How Ocrelizumab Works
Ocrelizumab, an anti-CD20 monoclonal antibody, targets mature B-cells. Almost 95 percent of the B-cell population has these antigenic epitopes after maturation and does not shed them, which is what makes it a potent marker for therapeutic purposes. It is believed that these CD20-positive B-cells target axons and myelin sheaths of healthy neurons, initiating a cascading series of immune reactions that lead to MS and disability in patients. Preclinical studies have shown that ocrelizumab binds to specific B-cells with CD20 markers but not to stem cells and plasma cells, preserving vital immune functions within the host.
Ocrelizumab’s Clinical Trials for MS
Roche recently announced favorable results from a pivotal Phase 3 trial called ORATORIO, a randomized, double-blind, global and multicenter study evaluating the efficacy and safety of ocrelizumab in 732 patients with primary progressive multiple sclerosis (PPMS). The drug was administered intravenously, as two infusions of 300 mg given two weeks apart every six months. At the end of the study period, it was seen that ocrelizumab had met the study’s primary outcome, significantly reducing clinical disease progression in PPMS patients sustained for at least 12 weeks by 24 percent (compared to placebo), as measured by the Expanded Disability Status Scale (EDSS).
In February 2016, the U.S. Food and Drug Administration (FDA) designated ocrelizumab a Breakthrough Therapy as a possible PPMS treatment, a decision meant to expedite its development and review.
Data from two related Phase 3 studies, OPERA I and II, testing the efficacy of the drug in 1,656 patients with relapsing forms of MS, found that ocrelizumab was superior to interferon beta-1a, a well-established MS therapy, reducing the annualized relapse rate (the primary endpoint of both studies) by nearly 50 percent over a two-year controlled treatment period. Ocrelizumab was administered intravenously at 600 mg every six months; interferon beta-1a was given by subcutaneous injection at 44 mcg three times per week.
Roche says OCREVUS is the first investigational medicine to show such positive results in patients with both primary progressive and relapsing forms of multiple sclerosis. The company submitted data from all three studies to regulatory authorities in mid-2016, potentially paving the way for FDA approval, marketing, and commercialization of ocrelizumab in the treatment of relapsing MS and PPMS. On June 28, 2016, Roche announced that the company’s Biologics License Application for OCREVUS for the treatment of relapsing multiple sclerosis and primary progressive multiple sclerosis had been accepted for FDA review, and that the therapy was given Priority Review Designation, which will accelerate the review process. A targeted action date for the therapy is set for December 28, 2016.
Note: Multiple Sclerosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.