PML Brain Infection Diagnosed in Gilenya User

A patient taking the multiple sclerosis drug Gilenya has been diagnosed with a rare and often fatal brain infection.

Known as progressive multifocal leukoencephalopathy, or PML, the infection attacks the white matter of the brain and is frequently linked to powerful immunosuppressant drugs.

On Friday, Novartis confirmed the report involving a patient diagnosed with a PML brain infection while on Gilenya, indicating that the individual had previously used Tysabri, another multiple sclerosis drug that is subject to severe restrictions on use due to the risk of the infection.

The report comes just days after the Institute for Safe Medication Practices (ISMP) indicated that use of Gilenya should be restricted, after the medication was linked to 286 adverse event reports in the second quarter of 2011, including six patient deaths, eight cases of permanent disability and 68 cases of infection.

The ISMP report concluded that the risk of Gilenya infections should cause the FDA to consider limitations similar to what is in place for users of Tysabri, which is highly restricted and patients are required to be heavily monitored for signs of PML. Tysabri was recalled at one point before being re-released under more stringent safety measures.

Novartis officials indicate that the reported brain infection with Gilenya use was most likely tied to the prior Tysabri use, but the contribution of Gilenya to the development of the infection can not be excluded.

Gilenya (fingolimod) was approved by the FDA in 2010 as an oral treatment for relapsing forms of MS in adults. It is used to reduce how often flare-ups occur and to delay the onset of physical disability caused by MS.

Despite concerns over the safety of Gilenya, the FDA agreed to fast-track the drug’s approval with minimal testing under a program aimed at getting crucial drugs to the market to address medication needs that have not been met by other drugs.

Prior to approval, the risk of some heart irregularities after the first dose were also a concern, as side effects of Gilenya are known to include a decrease in heart rate and/or atrioventricular condition after the first does. It is also known to increase the risks of vision loss and developing heart blocks or bradycardia when taken with some other drugs, including beta blockers and calcium channel blockers.

Im December, the FDA issued a drug safety communication to announce that it was investigating a reported death on Gilenya, which occurred less than 24 hours after receiving a dose of the medication.

A similar review earlier this year by European regulators led to a recommendation that doctors should closely monitor patients after giving them the first dose of the medication, and that doctors should conduct electrocardiogram monitoring before treatment and continue monitoring for the six hours after the patient takes the first dose.

Progressive multifocal leukoencephalopathy is an aggressive brain disease that is believed to be caused by the common JC virus. Many suspect that the virus becomes active after drugs suppress the immune system. In many cases, the infection results in death.

Symptoms of PML could include changes in mood, unusual behavior, confusion, memory loss, weakness or loss of strength on one side of the body, or problems with vision, speech or walking.