FDA updates label for Novartis' MS pill Gilenya after reports of brain infection

Novartis ($NVS) has faced its fair share of safety issues with Gilenya since the drug hit the market, with the FDA saying in 2013 that it would investigate a report that a patient taking the MS med had developed a rare but often fatal brain infection. Now the company is dealing with more regulatory pushback as the agency said it will update Gilenya's label to reflect cases of serious brain infections linked to the pill.

The FDA is pointing to one case of definite progressive multifocal leukoencephalopathy (PML) and another case of probable PML in MS patients taking Gilenya--a first among people who have not already been treated with an immunosuppressant drug, the agency said in a statement. In August 2013, the agency warned that a patient developed PML after taking the pill. The infection could not be definitively linked to Gilenya because the patient had already been treated with other drugs that can weaken the immune system.

Novartis tells FiercePharma in an email that it "continues to stand behind the positive benefit-risk profile of Gilenya in relapsing MS." Novartis pointed out it reported to health authorities the two cases cited in the label update and recently updated its prescribing information for the drug to reflect the risk of the virus that causes PML.

"Patient safety is of paramount importance for Novartis, and we have taken the appropriate steps to revise the Gilenya prescribing information to increase vigilance for PML," the company said. "This is to ensure physicians take the necessary measures in case of imaging or clinical signs suggestive of the disease."

The label update could complicate things for Novartis in the MS arena, where Gilenya competes with oral rivals including Biogen's ($BIIB) Tecfidera and Sanofi's ($SNY) Aubagio. As ISI analyst Mark Schoenebaum said in a note to investors, PML concerns have affected sales "to various degrees" for other drugs that docs were hoping weren't as risky. But Gilenya's label change "may get greater attention from doctors and at the least could serve as a talking point for competitor's drug reps," he said.

Still, Novartis continues to post promising numbers for Gilenya despite looming safety issues. The drug's sales jumped by 26% to $700 million during the company's second quarter as patients continue to favor oral MS meds over injectables. And Gilenya is getting "incrementally more share" in new patients, Bernstein analyst Tim Anderson said in a note to investors, potentially signaling more market opportunity for Novartis in the future.

- here's the FDA's safety announcement
- read the Reuters story

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