Combining Plavix, a costly "super-aspirin," with regular aspirin proved to be no more effective than aspirin alone for preventing heart disease.
In fact, the combination nearly doubled the death rate from heart disease among patients who had not had heart attacks but were at risk for them.
A study on the effects of Plavix divided over 15,000 patients with heart disease into two groups -- one that took Plavix and aspirin, and one that took aspirin with a placebo.
The only major difference was that almost 4 percent of those who took Plavix and had not had a heart attack died over the course of the study, as opposed to just over 2 percent of those who took only aspirin.
Plavix, which costs $3 to $4 a pill, has made more than $3 billion in sales since its approval in 2000.