Heart stent with new polymer matches Abbott top seller in study

(Reuters) - A drug-coated heart stent from Japan's Terumo Corp with a dissolving polymer proved just as effective as Abbott Laboratories' top-selling Xience stent at preventing a second procedure to clear the artery, a large study found.

Stents are small wire-mesh structures inserted into narrowed coronary arteries to restore proper blood flow. Many models are coated with a polymer that slowly releases a drug designed to prevent another blockage and repeat procedure.

New drug-coated stents with dissolving polymers are being developed in response to data showing the older so-called durable polymers may trigger an inflammatory reaction that raises a patient's stroke risk.

In the study of more than 3,200 patients, Terumo's Nobori stent met its primary goal of non-inferiority to the Xience stent one year after implantation, with 4.2 percent of patients in both groups requiring a repeat procedure.

Patients also had low similar rates of stent thrombosis, or device-related blood clot formation, with both the Nobori and Xience stents. The study, sponsored by Terumo and conducted by researchers at Kyoto University, was presented Sunday at the American College of Cardiology scientific meeting in San Francisco.

Abbott's Xience stent is the market leader in Japan with a 50 percent share and the top-selling U.S. drug-coated stent with a 40 percent share.

The company is developing a new stent, called Absorb, that completely dissolves away in the body. It will present data on that device at the ACC meeting on Monday.

Abbott's U.S. stent rivals are Boston Scientific Corp and Medtronic Inc.

(Reporting By Susan Kelly in Chicago; Editing by Diane Craft)