First Case of PML with Ocrevus is Reported

An individual with multiple sclerosis (MS) in Germany has developed progressive multifocal leukoencephalopathy (PML) following three years of treatment with Tysabri® (natalizumab) and one dose of Ocrevus™ (ocrelizumab). PML is a potentially fatal brain infection that can occur in people with a weakened immune system, which can result from taking an immunosuppressant. An increased risk of PML has previously been linked to Tysabri, which was approved by the United States Food and Drug Administration (FDA) in 2004 for the treatment of relapsing forms of MS. The last dose of Tysabri was given to this patient in February 2017 and the first dose of Ocrevus was given in April 2017. This case is currently under investigation to see what roles either treatment may have played in the development of PML.

Additionally, this individual had tested positive for the JC virus, which means that the patient possessed the virus necessary to develop PML. The JC virus typically remains dormant in those exposed to the virus, but may become active when the immune system is weakened. Three risk factors have been associated with taking Tysabri and developing PML; these include exposure to the JC virus, a longer duration of Tysabri treatment (particularly two years or more), and prior treatment with an immunosuppressant medication.

Ocrevus was approved by the FDA on March 28, 2017. It is the first disease-modifying therapy to be approved for two types of multiple sclerosis (MS): relapsing forms of MS (RMS) and primary-progressive MS (PPMS). While no cases of PML had occurred in the studies or prior to the approval, a cautionary warning of the possibility of PML was included in the labeling for Ocrevus.

MSAA will provide updates on this topic as more details become available. For additional information on MS or to speak with a trained Client Services Specialist, please call MSAA’s Helpline at (800) 532-7667, extension 154. Questions to MSAA’s Client Services department may also be emailed to

Written by Susan Courtney, MSAA Senior Writer
Reviewed by Dr. Jack Burks, MSAA’s Chief Medical Consultant