Endeavor® vs. Taxus®: Medtronic’s Drug-Eluting Coronary Stent Linked to Fewer Heart Attacks at Two Years Post Implant

Latest Data from ENDEAVOR-IV Also Highlight Extremely Low Rates of Very Late Stent Thrombosis with Endeavor DES

Two-year results from the ENDEAVOR-IV clinical trial show that the Endeavor drug-eluting stent (DES) from Medtronic, Inc. (NYSE: MDT), is associated with statistically fewer heart attacks than Boston Scientific’s Taxus® DES.

Dr. Martin B. Leon, founder and chairman emeritus of the Cardiovascular Research Foundation and principal investigator of ENDEAVOR-IV, presented the results today at the Transcatheter Cardiovascular Therapeutics (TCT) meeting as part of a late-breaking clinical trials session.

“Through two years of follow up in the ENDEAVOR-IV clinical trial, the Endeavor drug-eluting stent has proven to be statistically safer than Taxus on the important measure of myocardial infarction, and no different in terms of efficacy as measured by the need for repeat procedures,” said Dr. Leon. “The latest data clarify the comparative safety and efficacy of these two drug-eluting stents beyond one year. As importantly, the data also show that Endeavor is associated with numerically fewer instances of very late stent thrombosis.”

Referencing the long-term follow-up in the extensive ENDEAVOR clinical program, Dr. Leon added: “These safety and efficacy findings are remarkably consistent across the complete set of randomized trials, registries and pooled datasets that have featured the Endeavor stent.”

In ENDEAVOR-IV, only one of the Endeavor patients (n=742) experienced a very late stent thrombosis (ARC definite/probable), compared to six of the Taxus patients (n=739): 0.1 percent vs. 0.8 percent (p=0.069). Very late stent thrombosis (VLST) is a rare but potentially fatal complication in which a blood clot forms around the stent a year or more after implant. VLST usually causes death or myocardial infarction (MI).

Differences in duration of dual-antiplatelet therapy (DAPT) between the two groups underscore the safety benefits of the Endeavor stent. While a significantly greater proportion of patients randomized to the Taxus stent received DAPT to two years of follow-up (p=0.02), the Taxus patients experienced a 50 percent increased incidence of MI (p=0.02) and a six-to-one higher ratio of VLST (p=0.06).

Similarly to the VLST rates, the two-year follow-up on the primary endpoint of target vessel failure (TVF) – a composite of death, MI and target lesion revascularization (TLR) – favored Endeavor patients numerically compared to Taxus patients: 11.1 percent (82/742) vs. 13.1 percent (97/739) (p=0.232), driven by a 34 percent reduction in cardiac death and MI to two years.

Sean Salmon, vice president and general manager of the Coronary and Peripheral Vascular business at Medtronic, summed up the head-to-head trial’s findings: “The results of ENDEAVOR-IV suggest that for every 1,000 patients treated with either Endeavor or Taxus, similar numbers would need a repeat procedure by two years; but compared to the Taxus patients, the Endeavor patients would experience eight fewer heart attacks between one year and two years post implant. While these calculations assume a population of patients like those in ENDEAVOR-IV, the data increase the body of knowledge with which clinicians are armed when making important therapy-selection decisions for their patients.”