Reed Miller

September 28, 2010

September 28, 2010 (Seoul, Korea) — Twelve-month results from the ZEST trial, comparing the safety and efficacy of a zotarolimus-eluting stent with a sirolimus-eluting stent and a paclitaxel-eluting stent, are now published in the October 5, 2010 issue of the Journal of the American College of Cardiology [1].

As reported by heartwire , the one-year ZEST results were announced by study coauthor Dr Seung-Jung Park (Asan Medical Center, Seoul, South Korea) at the American College of Cardiology 2009 Scientific Sessions in Orlando, FL.

The 19-center, single-blind, prospective trial led by Dr Duk-Woo Park (Asan Medical Center) randomized 2645 non-ST-elevation-MI patients with either stable angina or acute coronary syndromes to the Endeavor zotarolimus-eluting stent (Medtronic), the Cypher sirolimus-eluting stent (Johnson & Johnson/Cordis), or the Taxus Liberté paclitaxel-eluting stent (Boston Scientific).

The primary end point was a composite of major adverse cardiac events (MACE), including death, MI, and ischemia-driven target vessel revascularization at 12 months. The authors calculated a noninferiority comparison between the Endeavor and the Cypher and a superiority comparison between the Endeavor and Taxus for the primary end point at one year. The Endeavor group showed noninferior rates of MACE compared with the Cypher group (10.2% vs. 8.3%; p for noninferiority=0.01, p for superiority=0.17) and significantly fewer MACE than the Taxus group (10.2% vs. 14.1%; p for superiority=0.01). The incidence of death or MI was similar among the groups (Endeavor vs Cypher vs Taxus, 5.8% vs 6.9% vs 7.6%, respectively; p=0.31), but stent thrombosis was significantly less common in the Cypher group than in either the Endeavor or Taxus group (0% vs 0.7% vs 0.8%, respectively; p=0.02).

"The most consistent finding of the ZEST trial is that [the sirolimus-eluting stent] is associated with the lowest angiographic restenosis, with lowest need for [target lesion revascularization] TLR, and with the lowest risk of stent thrombosis among the three tested types of [drug-eluting stents] DES," the authors point out. "This might suggest that newer DES platforms are not always better than older ones."

ZEST's major findings were consistent across high-risk subpopulations, including patients with diabetes, long lesions, small vessels, and multivessel disease, so "the findings can be extended to a broader spectrum of patients and provide a high level of generalizability to routine clinical practice," Park et al explain. The authors point out that the ZEST results are similar to the recent results from the SORT OUT III study and ENDEAVOR IV trial. But larger studies with longer-term follow-up, such as the PROTECT study, are needed to provide a better picture of the stents' relative safety, Park et al note. PROTECT is enrolling 8800 patients at about 200 hospitals to evaluate whether the Endeavor stent protects against late stent thrombosis, resulting in fewer deaths and MIs over three years of follow-up.

The ZEST study was supported by the CardioVascular Research Foundation, Seoul, Korea, and Medtronic Vascular. Seung-Jung Park reports consulting fees from Cordis; lecture fees from Cordis, Medtronic, and Boston Scientific; and research support from Cordis and Medtronic.