The “powerful” arthritis drug Bextra from drug giant Pfizer increases a patients’ risk of heart attack and stroke, according to preliminary results of a study presented yesterday at the American Heart Association meeting in New Orleans, the New York Times reported on Wednesday.

The study found that patients taking Bextra experienced twice the number of heart attacks or strokes compared with those given placebos.

“The magnitude of the signal with Bextra is even higher than what we saw in Vioxx,” Dr. Garret A. FitzGerald, a cardiologist and pharmacologist at the University of Pennsylvania, said in an interview after presenting the data. “This is a time bomb waiting to go off.”

In a press release, Pfizer responded to the New York Times article by asserting that it draws unsubstantiated conclusions about the cardiovascular safety of Bextra and is based on information that has not been published in a medical journal or subject to independent scientific review.

However, Pfizer disclosed in October that two studies in a high-risk surgery known as coronary artery bypass graft, an increase in cardiovascular events was observed in patients taking Bextra alone or in combination with an injectable pro drug of Bextra.

*Pfizer emphasized that Bextra is not approved for use in any surgical setting in the United States.

(via New York Times)