As of September 2, 2014, there have been 495 PML cases among Tysabri-treated patients. All but 3 of the cases have been people with MS. The 3 other cases have had Crohn's disease.
At present the risk of PML is about 3.72 per 1,000, and the death rate for the PML patients is at 22%
The data is based on a total of 129,100 patients ever treated with Tysabri up to 6/30/14.
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