NEW YORK (TheStreet) -- Bristol-Myers Squibb (BMY) and Pfizer's (PFE) apixaban drug showed promise in preventing strokes in a clinical study, the companies said Sunday.

In a Phase 3 trial, the drug, which has the commercial name ELIQUIS, was compared with another drug, warfarin, in 18,201 patients with atrial fibrillation and at least one risk factor for stroke.

Compared with warfarin, apixaban reduced the risk of stroke or systemic embolism by 21%, major bleeding by 31% and mortality by 11%, the companies said.

The companies are developing the drug to prevent and treat blood clots.

"The risk for stroke in patients with atrial fibrillation is a major public health concern in an aging population," Dr. Christopher B. Granger, a professor of medicine at Duke University Medical Center and lead investigator of the study, was quoted saying in a news release from Bristol-Myers and Pfizer.

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"We are therefore encouraged by the outcome of the ARISTOTLE trial, which showed that apixaban, as compared with warfarin, significantly reduced the risk of stroke or systemic embolism, major bleeding, and mortality," Granger said.

The clinical trial results were presented at a medical conference in Paris and published in The New England Journal of Medicine.

Shares of Bristol-Myers Squibb closed Friday up 24 cents at $28.72, while shares of Pfizer ended the session up 25 cents at $18.21.

This article was written by a staff member of TheStreet.

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