Quoted from http://online.wsj.com/article/BT-CO-20120413-704136.html
Novartis MS Pill Gilenya Patient Gets Rare Brain Disease
By Marta Falconi
Of DOW JONES NEWSWIRES
ZURICH (Dow Jones)--Novartis AG (NVS) Friday said a patient treated with its multiple-sclerosis pill Gilenya has been diagnosed with a rare and often fatal brain disease.
The Swiss drug maker said the patient, whose identity has not been disclosed, had been previously treated with another MS drug, Tysabri, co-marketed by Biogen Idec Inc. (BIIB) and Elan Corp. PLC (ELN), which has been already associated with progressive multifocal leukoencephalopathy, or PML.
"The current assessment is that Tysabri is the drug most likely associated with this case of PML," Novartis said in a statement. "However, a contribution of Gilenya to the evolution of this case can't be excluded."
The development comes at a critical time for Novartis' Gilenya, whose safety profile has recently come into question after the death of one person in the U.S. last autumn within 24 hours of starting treatment. Heart problems in some patients were also reported.
The European Medicines Agency, the body responsible for licensing Gilenya in Europe a year ago, is expected to issue a decision on the safety of the medicine following an in-depth review on April 20.