"As of the 30th November there have been 312 confirmed cases of Natalizumab-related PML! Slide 5, 6 and 19 give you the latest risk stratification figures."
"If you are on natalizumab or considering starting it please ask your MS team to arrange a serological test to see if you are JCV sero-positive or negative. Your JCV serostatus is an important component of the risk stratification tool."
Source: Biogen-Idec
CoI: multiple