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FDA Investigating Case of PML in Person Receiving Gilenya

August 29, 2013

UPDATED 3/13/15

The U.S. Food and Drug Administration (FDA) is investigating a case of PML (progressive multifocal leukoencephalopathy, a viral infection of the brain that usually leads to death or severe disability) that occurred in a person taking Gilenya® (fingolimod, Novartis AG). This person had not previously received Tysabri® (natalizumab, Biogen Idec); read more about the increased risk of PML in people taking Tysabri here). It is not yet known what caused the occurrence of PML in this case.

According to the agency statement, “Patients should not stop taking Gilenya without first discussing any questions or concerns with their health care professionals.” The FDA is working with Novartis to obtain and review all available information about this case of PML and will communicate final conclusions and recommendations after the evaluation is complete.

The statement relates that the person who developed PML received nearly eight months of Gilenya treatment before being diagnosed with PML. The person had been treated with interferon beta-1a and azathioprine (an immunosuppressant) for one month before initiating Gilenya treatment, as well as multiple courses of intravenous corticosteroids for several months before and during treatment with Gilenya. It is not yet known what caused the occurrence of PML in this case.

UPDATE: According to a statement from Novartis, this individual’s underlying disease was an aggressive form of Neuromyelitis Optica spectrum disorder (NMO) and not multiple sclerosis. A definite link between PML and Gilenya in this person has not been established.

Gilenya was approved by the FDA in 2010 for adults with relapsing forms of MS to reduce the frequency of clinical relapses and to delay the accumulation of physical disability. Gilenya is a new class of medication called a sphingosine 1-phosphate receptor modulator, which is thought to act by retaining certain white blood cells in the lymph nodes, thereby preventing those cells from crossing the blood-brain barrier into the brain and spinal cord. FDA approval was based on positive results from two large-scale phase III clinical trials which showed that fingolimod significantly reduced multiple sclerosis relapse rates and reduced disease activity as measured by MRI.

Read more about Gilenya here.

Gilenya is a registered trademark of Novartis AG.
Tysabri is a registered trademark of Biogen Idec.

About Multiple Sclerosis

Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system that disrupts the flow of information within the brain, and between the brain and body. Symptoms range from numbness and tingling to blindness and paralysis. The progress, severity and specific symptoms of MS in any one person cannot yet be predicted, but advances in research and treatment are leading to better understanding and moving us closer to a world free of MS. Most people with MS are diagnosed between the ages of 20 and 50, with at least two to three times more women than men being diagnosed with the disease. MS affects more than 2.3 million people worldwide.


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