The attached article was on the BBC website today.
The drug is not currently used for MS but Dacluzimab which is also an anti-transplant rejection drug is in trial. The moral of the story is that while you can affect the immune system by using heavy duty drugs there is always a price to pay - in this story the price is skin cancer. We are now aware of bad side effects (including death) from heavy immune suppressing drugs such as Tysabri and Campath. Hopefully future treatments will be more focused and not wreck the entire immune system. Tovaxin looks more promising in this respect.