Tysabri, the MS Drug Haunted by Deadly Side Effect, Doesnt Look So Deadly Anymore
Summary
But now with three years of data from more than 60,000 patients worldwide who have taken natalizumab (Tysabri) under strict monitoring by physicians, a new picture is emerging that shows PML is still very much a serious threat, but that it isn’t nearly as deadly as first feared.This drug, an antibody treatment designed to block certain white blood cells that cause MS when they attack nerves, has a history of also making patients vulnerable to infection.But legions of patients still demanded the drug, considered to be the most effective medicine on the market at reducing the disabling nerve damage from multiple sclerosis flare-ups.The FDA allowed the drug to return to the market in July 2006 after determining its benefits outweighed the risks, but it also forced doctors into a strict monitoring program to keep an eye out for the early signs of PML.(The importance of this drug is one reason why investors get so ticked at Biogen when it isn’t exactly forthcoming about every newly diagnosed case, but that’s a bone to pick another day.)