PARIS – The Xience everolimus-eluting coronary stent is widely considered the current standard treatment, implanted by interventional cardiologists far more often than any other drug-eluting stent (DES). But judging from the results of the TARGET All Comers trial, some serious competition may be headed Xience’s way in the form of the new Firehawk rapamycin-eluting, thin-strut stent featuring a biodegradable polymer drug delivery system.
What’s more, the Firehawk offers a theoretical advantage in that the rapamycin is delivered via a polymer that’s fully absorbed by 9 months, leaving behind a bare metal stent made of cobalt chromium. This structure is believed to be less proinflammatory, atherogenic, and thrombogenic over the long haul, compared with a permanent durable polymer, such as that employed in the Xience stent. This should translate into less late restenosis and in-stent thrombosis.
Also, the Firehawk features thin, 86-mcm struts and the rapamycin, also known as sirolimus, is contained in abluminal grooves directed specifically to the vessel wall. As a result, this DES exposes patients to only one-third as much active drug as other DESs. Ninety percent of the rapamycin is released within 90 days after implantation, according to Dr. Baumbach, director of interventional research at Barts Heart Centre in London and president of the European Association of Percutaneous Cardiovascular Interventions.
The TARGET All Comers trial is a prospective, open-label, noninferiority trial comparing the safety and efficacy of the Firehawk with those of Xience stents in 1,656 DES-eligible patients with symptomatic coronary artery disease randomized at 21 centers.
The primary endpoint was the 12-month composite of target lesion failure, comprising rates of cardiac death, target vessel MI, or ischemia-driven target lesion revascularization. In an intention-to-treat analysis, the rate was 6.1% in the Firehawk patients and 5.9% in the Xience recipients. Results for each of the three components of the composite endpoint were similar in the two groups as well.
A secondary endpoint was in-stent late loss as measured by quantitative coronary angiography at 13 months in a 137-patient subgroup. The rate was 0.17 mm in the Firehawk recipients and similar at 0.11 mm in those receiving the Xience stent, again, which provided solid evidence of noninferiority.
The rate of definite stent thrombosis at 1 year was 1.2% in both study arms.
Discussant Giulio Guagliumi, MD, an interventional cardiologist at Pope Giovanni XXIII Hospital in Bergamo, Italy, pronounced the results “quite reassuring.” But where, he asked, is the evidence of late benefit for the completely biodegradable polymer utilized in the Firehawk?
“We would expect to see such an effect later on, after the stent in question becomes a simple bare metal stent as opposed to a stent with a durable polymer. But we don’t have the ultimate answer yet. In this trial we will have an extended follow-up out to 5 years to see whether there is any translation of these differences into clinical benefit,” Dr. Baumbach replied.