Shares of drug giants Pfizer (PFE) and Bristol-Myers Squibb (BMY) posted solid gains Thursday morning amid enthusiasm for the results of a trial on a key blood thinner.

Late Wednesday Bristol-Myers and Pfizer said the drug, Eliquis, successfully met primary and key secondary endpoints in a Phase III study compared with Warfarin.

New York-based Bristol-Myers said it plans to submit regulatory filings in the U.S. and Europe for the drug in the third or fourth quarter after releasing detailed results in August.

The drug companies already received regulatory approval for Eliquis for the prevention of venous thromboembolic events in adult patients who have undergone hip or knee replacement surgery in the European Union.

Bristol-Myers and Pfizer reached a deal in 2007 to collaborate on developing and commercializing the drug.

Shares of Bristol-Myers jumped 5.34% to $29.21 Thursday morning and earlier hit a 52-week high of $29.54. Pfizer, the worlds largest drug maker, gained 2.17% to $20.73.

The positive news about Eliquis means increased competition for Xarelto, a drug that is awaiting FDA approval and was developed by Bayer and Johnson & Johnson (JNJ). 

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