Drug-eluting Stents Prove More Effective, Equally As Safe As Bare-metal Stents

The study, HORIZONS-AMI (Harmonizing Outcomes with RevascularIZatiON and Stents in Acute Myocardial Infarction), showed that in heart attack patients undergoing angioplasty, the use of paclitaxel-eluting stents reduces rates of target lesion revascularization (TLR) and binary angiographic restenosis when compared to the use of bare-metal stents after 1 year.

Additionally, the primary safety measure of major adverse cardiovascular events (MACE), including death, reinfarction, stent thrombosis and stroke established the non-inferiority of drug-eluting stents with respect to safety through 1 year.

The study, led by Gregg W. Stone, M.D., of the Cardiovascular Research Foundation and professor of medicine at Columbia University Medical Center/New York-Presbyterian Hospital, was sponsored and managed by the Cardiovascular Research Foundation with research grant support from Boston Scientific Corporation and The Medicines Company.

In the trial, the use of paclitaxel-eluting stents resulted in a significant reduction of ischemia-driven target-lesion revascularization (TLR) at 12 months (4.5% vs. 7.5%). TLR, which was the primary efficacy endpoint of the trial, refers to the rate at which a particular lesion re-narrows following stent implantation severely enough to require either a repeat angioplasty or bypass surgery operation.

The use of paclitaxel-eluting stents also resulted in a significant reduction in binary restenosis after 13 months, which is the rate at which the artery re-narrows at least 50% following implantation of the stent, and was the secondary efficacy endpoint of the trial. The paclitaxel-eluting stent had a rate of 10.0% and the bare metal stent had a rate of 22.9%.

"Outcomes from prior registry and randomized trials of drug-eluting stents compared to bare metal stents in heart attack patients have been conflicting. These results now provide definitive evidence that paclitaxel-eluting stents are superior in efficacy to bare metal stents and have a comparable safety profile at 1 year," said Dr. Stone. "The findings from the HORIZONS-AMI trial will have a major impact on how decisions are made regarding drug-eluting and bare metal stents in the highest risk patients, those in the early hours of a heart attack. This study removes much of the uncertainty and concern about the efficacy and safety of drug-eluting stents in this clinical setting. Moreover, all of the patients in this trial will be followed long-term to ensure that these favorable results are maintained."

The HORIZONS-AMI trial, a prospective, open-label, multicenter, controlled study, enrolled 3,602 heart attack patients at 123 centers in 11 countries, 3,006 of whom were randomized to paclitaxel-eluting stents versus otherwise identical bare metal stents.