Two studies sharpen the debate about the potential benefits and risks of a new anti-clotting drug.The drug, sold as Exanta (ximelagatran), is a potential replacement for Coumadin (warfarin), which can, among other things, prevent stroke in people with the heartbeat abnormality known as atrial fibrillation. While Coumadin is widely prescribed it is also notoriously difficult to manage, requires frequent blood tests to monitor clotting levels, and has adverse reactions with a number of other drugs.Exanta has none of those problems. However, the U.S. Food and Drug Administration (FDA) has not approved its use in this country, and several European countries have approved the drug only for limited purposes, because some people who take it experience increases in levels of an enzyme associated with liver damage.The studies in the Feb. 9 issue of the Journal of the American Medical Association try to tackle this issue; one looked at people with atrial fibrillation and the other reported on those with deep vein thrombosis.
