Increased competition in the $2 billion U.S. market for drug-coated heart stents has coincided with price declines among older devices sold by Boston Scientific Corp. (BSX) and Johnson & Johnson (JNJ).

The companies, which were early adopters in the market for the tiny heart devices, have noted price declines in recent quarterly reports. The domestic market became more crowded last year when both Medtronic Inc. (MDT) and Abbott Laboratories (ABT) entered the fray.

The highly profitable tools, which prop open clogged heart arteries and use medication to fight renarrowing, generally cost around $2,100 each. J&J brought the first coated stent to the U.S. in 2003 and Boston Scientific followed suit in 2004.

Samuel Leno, Boston Scientific's chief financial officer, noted on a call with analysts Tuesday that U.S. prices for the company's Taxus stents were down 7% from a year ago, which is in-line with the company's estimates and doesn't mean it's cheaper than other devices. Boston Scientific has two different coated-stent lines now, and the Taxus line is the older one, although it was recently refreshed with an updated version.

Meantime, Johnson & Johnson said last week that the estimated U.S. price for its Cypher stents declined 5% in the first quarter compared with the year-earlier period. That follows a 6% year-over-year decline in the fourth quarter.

Though Taxus has maintained a relatively strong market position - Boston Scientific believes the device is tied with an Abbott stent for the domestic lead - its estimated 27% U.S. market share is down sharply from the days it commanded more than half the market. J&J's Cypher has also seen its U.S. market share plummet due to fresher competition.

Abbott's Xience stent has been the main culprit, as Medtronic's Endeavor device has staked out a much smaller market position. John Thomas, the vice president of investor relations at Abbott, indicated last week that Xience prices haven't recently changed.

There is "a little bit of pricing pressure" in the market, Thomas said on Abbott's first-quarter earnings call, while noting J&J's comments. Some products "have to compete on price," he said.

Medtronic, which is on an unusual fiscal calendar and will next report quarterly results in May, didn't have figures immediately available on its stent prices.

While Taxus prices may be lower, James Tobin, Boston Scientific's chief executive, noted on Tuesday that prices for Taxus and the company's newer Promus stents are still $100 above the competition.

Tobin cited data from research firm Millennium Research Group, and said Boston Scientific's broad offering of products including two stents "lets us not have to compete on price as directly as the guy that has one."

Millennium declined to share its data on stent prices from the most recent quarter. According its "Interventional Cardiology Marketrack data", coated stents in the U.S. sold for an average $2,091 in the fourth quarter.

The firm also declined to say whether, on average, overall prices have been heading up or down, although Boston Scientific said in January that for the fourth quarter, average selling prices in the U.S. were down 8% for the entire industry compared with the year-earlier period.

Boston Scientific shares the profits from Promus stents with Abbott, which makes them under an agreement tied to the 2006 purchase of Guidant Corp. Promus and Xience are the same devices sold under different names.

-By Jon Kamp, Dow Jones Newswires; 617-654-6728; jon.kamp@dowjones.com