Pfizer (PFE) and Bristol-Myers Squibb (BMY) announced on Sunday strong study results for their drug used to prevent strokes and systemic embolisms.

In a study with more than 18,200 patients with atrial fibrillation and at least one risk factor for stroke, the drug, called eliquis, significantly reduced the risk of stroke or systemic embolism by 21%, major bleeding by 31% and mortality by 11% when compared with warfarin.

The risk for stroke in patients with atrial fibrillation is a major public health concern in an aging population, said Dr. Christopher Granger, professor at the Duke University Medical Center, and lead investigator of the study.

The drugs team, he said, was encouraged by the outcome of the trial.

Eliquis is part of a class of agents being studied as a potential prevention and treatment of blood clots. The drug is not currently approved for the prevention of stroke or systematic embolism in patients with atrial fibrillation in any country.

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