Quoted from http://online.wsj.com/article/SB10001424052748703573604574491212194615886.html
Europe Takes Closer Look At Tysabri
By THOMAS GRYTA
A European panel has started a review of the controversial multiple sclerosis drug Tysabri, sold by Biogen Idec Inc. and Elan PLC, citing a higher rate of a rare brain infection than previously disclosed.
The additional cases are important because they may increase the drug's risk profile and raise questions about the companies' responsibility in updating the market on the safety record of Tysabri, a product that generates nearly $1 billion in yearly revenue.
The European Medicines Agency's Committee for Medicinal Products for Human Use, known as CHMP, reported there have been 23 cases of progressive multifocal leukoencephalopathy, or PML, a number that the Food and Drug Administration later confirmed, adding that those cases were after Tysabri returned to the market in 2006. The FDA said it is continuing to assess the situation.
Previously, there had only been 13 confirmed cases of the infection since the drug re-entered the market in 2006, after being removed for 18 months because of a link to three other PML cases.