東京日和＠元勤務医の日々

By Susan Kelly

CHICAGO (Reuters) - Boston Scientific Corp.'s (BSX.N: Quote, Profile , Research) stock slid to a 4-1/2-year low on Monday while shares of Abbott Laboratories Inc. (ABT.N: Quote, Profile , Research) jumped after a study showed Abbott's drug-coated stent was better at treating clogged heart arteries.

"Over the weekend, the competitive landscape in drug-eluting stents was effectively turned on its head," JP Morgan analyst Michael Weinstein said in a note to clients.

Abbott released data at a major medical meeting on Saturday that showed its Xience drug-eluting stent was superior to Boston Scientific's market-leading Taxus stent in both its primary goal of reduced reclogging and a secondary goal of fewer adverse cardiac events.

Shares of Boston Scientific fell $1.15 or 7.56 percent to $14.07 in trade on the New York Stock Exchange, while Abbott's stock was up $2.64 or 4.9 percent to $56.50, also on the NYSE.

The study results, which will be used to seek U.S. approval for the device, were presented at a meeting of cardiologists in New Orleans.

Johnson & Johnson (JNJ.N: Quote, Profile , Research) also sells drug-coated stents in the United States, while Abbott and Medtronic Inc. (MDT.N: Quote, Profile , Research) sell them in overseas markets and are preparing to sell them here.

"Results from Abbott's U.S. and European DES trials should catapult the company's Xience product into a leadership position in both markets come 2008," Weinstein said.

Weinstein and other analysts raised their earnings estimates for Abbott Laboratories following the results.

Morgan Stanley analyst Glenn Reicin said Xience will likely gain market share at the expense of Taxus.

"The Spirit III results reinforce the view that Xience will likely be viewed as the 'best in class' DES for the remainder of the decade," Reicin said.

BMO Capital Markets analyst Joanne Wuensch cut her investment rating on Boston Scientific to "market perform" from "outperform" on Monday, citing the study and renewed worries about the overall health of the market for the wire-mesh devices that emit drugs to prevent vessels from narrowing again.

Pricier stents coated with drugs virtually replaced bare-metal stents when introduced over three years ago, generating almost 90 percent of all stent sales by early 2006. Now, some physicians are switching back to bare metal amid evidence that the drug-eluting versions carry a small but serious risk of blood clots forming long after the stents are implanted.

The percentage of patients receiving drug-eluting models has fallen to just above 70 percent, according to Boston Scientific.

There is also concern that a large study of patients with coronary artery disease and chest pain, also due to be presented at the medical meeting, will suggest that stents are being overprescribed.