Actually, that is not quite correct. In the 3 cases in the past the individuals that contacted PML were also on avonex or another dmd at the same time that they were being treated with tysabri. In these 2 current cases, one had been on some type of dmd's in the past and for the other this was his/her first type of treatment. But the drug company has stated repeatedly in the past or on their literature that expect more cases of PMl in the future.
But it also intersting that they say that the one individual is recovering at home as in the past there has been no succesful treatment for individuals with ms who contact pml. From what I have read they have been getting the tysabri out of their systems quickly through a plasma exchange. So that would be wonderful if they are able to figure out how to treat PML's.
Diagnosed April 2007
Started betaseron -- May 2007 -- experienced allergic reactions after 2 weeks
Started copaxone -- June 2007 -- stopped after 4 1/2 months;experienced severe 5 IPIR's
Started tysabri -- December 2007
Stopped tysabri -- April 2008 (developed antibodies/severe reactions)