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Tests may boost Boston Scientific stent rival

MUNICH -- Medtronic Inc. will report today that its stent for preventing heart attacks didn't cause blood clots in tests, increasing the company's chances of expanding its share of the $5.4 billion-a-year worldwide market.

The results, to be presented at a scientific meeting in Barcelona, suggest that experimental devices may be safer than those sold by Johnson & Johnson and Boston Scientific Corp. Research reported last year found that marketed models of the tiny tubes that prop open clogged coronary arteries can cause clots and may be no more useful than drug therapy.

Medtronic's Endeavor, designed to mimic a natural cell membrane, hasn't shown signs of clots after three- and four-year studies, said Andreas Zeiher, head of the cardiology unit at the University of Frankfurt. Medtronic and Abbott Laboratories, also developing a new type of stent, may take half the market from the current industry leaders next year, analysts say.

Stents are tiny metal mesh tubes that keep arteries open after doctors have cleared clogged vessels with tiny inflatable balloons. To suppress the growth of scar tissue that can block the blood vessel, device makers started coating stents with drugs used to suppress the immune system in cancer patients.

For the past year, the coated stents have raised concerns about blood clots, damaging sales of U S -approved stents made by Boston Scientific of Natick and New Brunswick, N.J. -based J&J, called Taxus and Cypher. Doctors reduced their use of coated stents and returned to the older, bare-metal versions to reduce risks in the sickest heart patients. The coating may be one reason for the clots, doctors say.

Endeavor, which belongs to the second generation of drug-coated stents, didn't perform worse than Cypher and Taxus stents in comparable studies, Zeiher said. Abbott Park, Ill. -based Abbott's Xience is thinner and more flexible than competitors, said Samin Sharma, director of interventional cardiology at Mount Sinai Medical Center in New York.

After a trial this spring showed Abbott's Xience stent is superior to Taxus in keeping treated blood vessels open, Abbott will present data in Barcelona to show the device is safe.

Boston Scientific has the right to use the Xience patents on its own brand, Promus, and the company said it will market both Promus and Taxus.