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What types of MS does Ocrevus treat?

Medically reviewed by Judith Stewart, BPharm. Last updated on Feb 6, 2023.

Official answer


Ocrevus (ocrelizumab) is the first treatment approved for primary progressive multiple sclerosis (PPMS). It is also approved for the more common relapsing forms of multiple sclerosis.

What is Multiple Sclerosis?

Multiple sclerosis (MS) is a chronic disease that occurs when the immune system abnormally attacks the insulation and support around nerve cells (myelin sheath) in the brain, spinal cord and optic nerves, causing inflammation and consequent damage. Symptoms include muscle weakness, fatigue and difficulty seeing, and may eventually lead to disability.

  • Relapsing forms of MS (RMS) include people with relapsing-remitting MS (RRMS) and people with secondary progressive MS (SPMS) who continue to experience relapses. RRMS is the most common form of the disease and is characterized by episodes of new or worsening signs or relapses followed by periods of recovery. Most people with RRMS will eventually transition to SPMS, in which they experience steadily worsening disability over time.
  • Primary progressive MS (PPMS) is a debilitating form of the disease marked by steadily worsening symptoms but typically without distinct relapses or periods of remission. Approximately 15 percent of people with MS are diagnosed with the primary progressive form of the disease.

What is Ocrevus?

Ocrevus is a humanized monoclonal antibody designed to selectively target CD20-positive B cells, thought to be a key contributor to myelin damage. It works by binding to the CD20 cell surface proteins expressed on certain B cells so that important functions of the immune system may be preserved.

In the Phase III ORATORIO PPMS study, Ocrevus was shown to significantly slow disability progression in patients with primary progressive multiple sclerosis, and reduce signs of disease activity in the brain (MRI lesions) compared with placebo with a median follow-up of three years.

Ocrevus is administered by intravenous infusion every six months. The initial dose is given as two infusions given two weeks apart.

Side effects include infusion reactions and upper respiratory tract infections.

  • Genentech Press Release: FDA Approves Genentech’s OCREVUS™ (Ocrelizumab) For Relapsing and Primary Progressive Forms of Multiple Sclerosis Available at [Accessed February 16, 2021]
  • Food and Drug Administration. OCREVUS® Product Label. Available at [Accessed February 16, 2021]

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