In separate clinical trials, a drug called ocrelizumab has been shown to reduce new attacks in patients with relapsing remitting multiple sclerosis (MS), and new symptom progression in primary progressive MS.

Three studies conducted by an international team of researchers, which included Amit Bar-Or and Douglas Arnold from the Montreal Neurological Institute and Hospital of McGill University, have discovered that ocrelizumab can significantly reduce new attacks in patients with relapsing MS, as well as slow the progression of symptoms caused by primary progressive MS.