Brain Infection Prompts FDA Investigation of Gilenya

The FDA is alerting the public that the first case of progressive multifocal leukoencephalopathy (PML) has been reported in a multiple sclerosis (MS) patient in Europe after taking Gilenya (fingolimod; Novartis). 

RELATED: Neurologic Disorders Resource Center

PML is a rare and serious brain infection caused by the John Cunningham (JC) virus that damages the fatty covering of the brain called myelin. The JC virus is a common virus that is harmless in most people but can cause PML in people who have weakened immune systems. 

Some medications, including Gilenya, can weaken the immune system. Gilenya is indicated for the treatment of relapsing forms of MS, to reduce the frequency of clinical exacerbations and to delay the accumulation of physical disability.

The patient who developed PML received nearly eight months of Gilenya treatment before being diagnosed with PML. This patient did not previously receive Tysabri (natalizumab), an MS drug associated with a higher risk of PML. 

The patient had been treated with interferon beta-1a and azathioprine for one month before initiating Gilenya treatment; those medications were stopped when Gilenya was started. The patient also received multiple courses of intravenous corticosteroids for several months before and during Gilenya treatment. 

The diagnosis was made based on clinical symptoms and the detection of JC viral DNA in the cerebrospinal fluid. Gilenya treatment was stopped.

The FDA and Novartis are currently investigating the case; final conclusions and recommendations will be communicated after the evaluation is complete.  The FDA is urging healthcare professionals to report side effects involving Gilenya to the FDA MedWatch program.

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