TUESDAY, April 22, 2008 (HealthDay News) -- A new kind of drug-coated stent was better at keeping arteries open than an older stent in the first large-scale U.S. study of the device, researchers report.
"This study suggests that in terms of overall safety and effectiveness, the Xience stent is superior to the Taxus stent, in terms of reduction of major cardiovascular events such as heart attacks at the time of the procedure," said study author Dr. Gregg W. Stone, director of cardiovascular research and education at the Center for Interventional Vascular Therapy, New York-Presbyterian Hospital/Columbia University Medical Center.
But, Stone added, "it is still too early to say whether this translates into a reduction of overall deaths. All we can say is that it is superior to the Taxus stent with a one-year follow-up."
The findings are published in the April 23/30 issue of the Journal of the American Medical Association.
The Xience stent, developed by a division of Abbott Laboratories, is not yet available for use in the United States. An advisory panel of the U.S. Food and Drug Administration has recommended approval, and action is expected later this year.
If approved, the Xience stent would be the fourth drug-coated stent on the American market. It would compete with the Cypher, which is coated with the drug sirolimus and marketed by Johnson and Johnson; Taxus, a Boston Scientific product coated with paclitaxel; and the newest entry, Medtronic's Endeavor, coated with ABT-578, a chemical relative of sirolimus. The Xience stent is coated with a drug called everolimus.
All the drug-coated stents are designed to reduce the risk that the opened coronary artery will close again. It's not yet possible to say which one is superior, Stone said.
"It's very difficult to rank them 1, 2, 3, 4," he said. "That will be a personal decision based on performance, price and each physician's interpretation of the data."
But the Xience stent does have advantages, because both the stent itself and its drug coating are thinner than other products, Stone said. "In addition to this study, which suggested a better outcome, it is also flexible and easily usable, which makes it a very attractive option for physicians," he said.
The study was financed by Abbott. The journal report noted that the company had "the right to a nonbinding review of the manuscript," but that "approval of the sponsor was not required prior to submission."
"They did not have final approval as to what I wrote in this manuscript," Stone said.
In the study, 669 people with blocked coronary arteries were given the Xience stent and 333 got the Taxus stent. At nine months, 7.2 percent of the arteries with the newer stent had closed again, compared to 9 percent of those with the paclitaxel-coated stent. The overall incidence of major adverse events such as heart attacks at 12 months was 6 percent among the people getting the Xience stent and 10.3 percent in those getting the Taxus stent.
Dr. Manesh R. Patel, assistant professor of medicine at Duke University School of Medicine and co-author of an accompanying editorial in the journal, called the new research a good start but said the review process is still unfolding.
"We have to be careful in what we recommend," Patel said. "What we have now is information in this study that the everolimus-eluting stent is slightly better than the paclitaxel stent out to one year. We don't know the long-term results."
The people in the trial had relatively simple artery blockages, Patel noted. "In those patients, there was a clinical benefit, small but significant, but we need to be cautious as we apply it to a wider array of patients," he said.
The FDA has asked for a longer follow-up review of the new stent, which is appropriate, Patel said. "There is a possibility of a step forward, but I await future studies," he said. "I want to have the data in before I say that this one overtakes the other one."
A review of drug-coated stents is offered by the U.S. Food and Drug Administration.