No Gender Gap Found for Clot-Busting Drug

Nov. 10 -- MONDAY, Nov. 9 (HealthDay News) -- The widely used clot-dissolving drug Plavix (clopidogrel) works about the same in women as in men, an analysis of major clinical trials has found.

"After this study, I can say we can be confident in treating both men and women with this very important drug," said Dr. Jeffrey S. Berger, director of cardiovascular thrombosis at New York University Langone Medical Center in New York City and lead author of a report in the Nov. 17 issue of the Journal of the American College of Cardiology.

Clopidogrel acts by preventing blood cells called platelets from forming clots that block arteries. It is one of several antiplatelet drugs; aspirin is another. Clopidogrel is commonly prescribed to prevent clots in people with the abnormal heartbeat called unstable angina, or after a heart attack or the implant of a stent, a thin tube put in to keep arteries open.

The study looked at data from five major clinical trials of clopidogrel involving nearly 60,000 people, 30 percent of them women. Leaders of the trials worked together to determine how the drug worked in men and women.

"There have been a lot of preliminary suggestive data that men and women respond differently to antiplatelet medications," Berger said. "Up to this point, there have been no data on the benefits and risks of clopidogrel in women and in men. Is there a difference? Overall, we can say the answer is no."

The study is the latest example of the growing attention being paid to cardiovascular problems such as heart attack and stroke in women, a subject often overlooked in the past. Attention is being paid, Berger said, because a third to half of all heart attacks occur in women. Two recent studies reported that the incidence of heart attacks has increased in American women in the past two decades, while their chance of surviving heart attacks has improved.

At first glance, the raw data from the studies would seem to indicate a difference in male vs. female response to Plavix. The drug reduced cardiovascular events by 16 percent in men and 7 percent in women. The chief benefit for women was reduction of heart attack risk; for men it was reduction of strokes and cardiovascular deaths.