Tysabri reports 10 more brain disease cases

THE owners of multiple sclerosis drug Tysabri have reported a further 10 cases of the rare brain disease PML as a side-effect of using the treatment.

The latest monthly update on cases shows that eight of the cases — identified among Tysabri users in January — were in patients in Europe, with the other two in the US.

Tysabri is jointly owned by US pharmaceutical firm Biogen Idec and Ireland’s Elan. The Dublin-headquartered company doesn’t comment on PML numbers but is currently working on trials for a new blood test to determine the existence of the JC virus in MS sufferers.