Bristol-Myers Squibb and Pfizer said Thursday that federal regulators have expanded approval of their blood thinner Eliquis to treat two types of dangerous blood clots.

The Food and Drug Administration cleared the drug for patients suffering from or at risk of deep vein thrombosis and pulmonary embolism. The drug was originally approved in 2012 to treat a common form of irregular heartbeat, atrial fibrillation, in patients at risk for strokes or dangerous clots.

Eliquis, known chemically as apixaban, is manufactured by Bristol-Myers Squibb and co-marketed with Pfizer. Both companies are based in New York.

Deep vein thrombosis occurs when blood clots form in one of the large, deep veins, usually in the legs. Pulmonary embolism most commonly occurs when part or all of a thrombosis dislodges and travels to the lung, via the heart, where it can partially or completely block a branch of the pulmonary artery. Each year up to 900,000 Americans experience one of the clots, resulting in up to 300,000 deaths.

Xarelto, another blood thinner from rival Johnson & Johnsons, was approved to treat the same conditions in 2012.