Details
A case of progressive multifocal leukoencephalopathy (PML) has been reported in an individual being treated with Gilenya outside of Canada. Prior to starting treatment with Gilenya, the individual was treated with natalizumab (Tysabri) for approximately three and a half years. The individual was also reported to have tested positive for the JC virus (JCV) antibody. Treatment with Tysabri is associated with a known risk for PML, particularly in people who have tested positive for the JCV antibody–and those who have been treated with Tysabri for longer than two years. PML is a rare brain disease caused by the JC virus that can cause severe disability or death. The condition usually affects people with suppressed immune systems. The risk for PML with natalizumab is well known and measures have been taken to try to mitigate the risk.
This is the first case of PML reported in an individual treated with Gilenya and according to the marketing company Novartis, the case of PML is likely associated to the previous treatment with Tysabri. They cannot however rule out the contribution Gilenya may have had in the development of PML. In a press release, Novartis said that they believe that Gilenya provides a benefit for individuals with MS when used in accordance with approved labelling.
Health authorities including Health Canada, the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) are undertaking safety reviews of Gilenya following the reports of serious adverse events, including 11 deaths internationally.
Symptoms of PML should be immediately reported to the prescribing doctor and can include: progressive weakness on one side of the body, clumsiness of limbs, disturbance of vision, changes in thinking, memory and orientation, confusion and personality changes.
Individuals should not stop taking Gilenya without talking to their healthcare professional. For further information or questions related to Gilenya’s safety, individuals are encouraged to contact the patient support line at Novartis Pharmaceuticals Canada Inc. at 1-855-745-5467 or their prescribing doctor.