Inspire Pharmaceuticals is launching a Phase I clinical trial for a proposed drug to fight blood clots often associated with heart bypass surgery.

More than 500,000 Americans undergo bypass surgery each year, according to the American Heart Association.

Inspire has also filed a new drug application with the Food and Drug Administration for the drug, which is called INS50589.

A minimum of 28 healthy volunteers will be tested for safety and tolerability of the drug, which will be delivered intravenously.

“There is a distinct medical need for a platelet aggregation inhibitor that is rapidly reversible and that could potentially reduce complications arising from surgeries such as coronary artery bypass graft and valve replacements,” said Christy Shaffer, CEO of Inspire, in a statement. “This product candidate broadens and strengthens the depth of our pipeline. We look forward to announcing the results of this trial in mid-2005.”

Platelets contribute to the formation of blood clots to stop bleeding. The drug is designed to block the factor that activates platelets. Inspire noted that platelets can be activated during bypass surgery as blood is moved outside the body.

Inspire said the effects of its drug are rapidly reversible.