ZES Match or Exceed Performance of Earlier DES

SAN FRANCISCO, CALIF.—With the completion of several studies involving zotarolimus-eluting stents (Endeavor, Medtronic), the overall trend suggests a favorable safety profile and durable efficacy.  David E. Kandzari, MD, director of interventional cardiology at the Piedmont Heart Institute in Atlanta, Georgia, discussed the accumulated evidence on ZES at a scientific symposia session on Monday.

Kandzari said the ENDEAVOR trials show a pattern of stability in safety and efficacy outcomes over long-term follow-up. “I regard the Endeavor stent very much as a dark horse,” he said. “It is not the stent that is perhaps expected to win with regard to angiographic outcomes in the first term… but at the final finish line it is a stent that performs at least competitively to alternative DES.”

The ENDEAVOR clinical trials program has encompassed 13 trials, including five randomized controlled trials, and more than 20,000 ZES-treated patients. The ENDEAVOR III trial, which compared 323 ZES patients with 113 sirolimus-eluting stent patients (Cypher, Cordis), found a 5-year composite rate of death, MI, and target lesion revascularization of 21.8% for the SES patients and 13.6% for the ZES patients; this did not reach significance, but Dr. Kandzari called it a “strong statistical trend” (P=.054) (see Figure).

That study also found similar rates of TLR between the two groups at 5 years (P=.547). There were differences between the groups, though, with regard to the change in event rates between 9 months and 60 months of follow-up: the ZES group had an increase in MACE rate of 7.5% to 14.0% between those time points, and the SES group increased from 7.1% to 22.2%.

In the ENDEAVOR IV trial, there were 773 ZES patients and 775 paclitaxel-eluting stent (Taxus, Boston Scientific) patients, and again a clinical benefit was seen with ZES at 5 years. The rate of cardiac death or MI was 9.1% for PES and 6.4% for ZES (P=.048). Kandzari noted one interesting sub-analysis from the ENDEAVOR trials, in that women did better by some outcome measures than men; these included percentage neointimal obstruction and target vessel revascularization.

Seung-Jeung Park, MD, PhD, chief of cardiology at the Asan Medical Center in Seoul, discussed results of the recent LONG-DES IV trial during the same symposia session. LONG-DES  IV compared 250 patients who received ZES with 250 patients who received SES; all patients had lesions of at least 25 mm in length. The study met its non-inferiority primary endpoint of in-segment late loss at 9 months (P=.03), and there were no significant differences between the groups in terms of clinical outcomes at either 1 month or 12 months of follow-up. At the later time point, the MACE rate was 14.4% for the ZES patients and 16.0% for the SES patients (P=.65). Dr. Park concluded that the stents appear equally effective at treating long coronary artery lesions.