An experimental anti-clotting drug that Merck & Co. is developing was found to increase risk of dangerous internal bleeding in a second study, meaning it's unlikely to achieve the blockbuster status once expected — if it's even approved.
Vorapaxar is part of a new generation of
anti-clotting drugs meant to prevent the death and disability strokes
and heart attacks cause in the millions of people at risk for them.
Drugmakers have generally touted their compounds as more effective and
safer than Coumadin, known chemically as warfarin, the standard
treatment for decades despite the need for frequent blood tests because
getting the dosage right is so tricky.