Tysabri's label was recently changed to indicate that the longer patients remain on the drug, the greater their risk of a potentially deadly brain infection called progressive multifocal leukoencephalopathy (PML). Even though Tysabri is a more effective drug, patients are comfortable with inferior but safer options such as Teva Pharmaceutical's Copaxone, Novartis' Extavia, and Rebif from Pfizer.
After refusing to up its bid for Facet Biotech conceding the company to Abbott LabsBiogen Idec has
decided that the best use of its cash is to buy … itself. In
conjunction with its first-quarter earnings, Biogen announced that it
plans to repurchase and retire $1.5 billion worth of its shares.