Two-year results presented at ACC from the Medtronic ENDEAVOR III trial confirm the positive clinical profile of the Endeavor drug-eluting coronary stent. Nearly 1,300 Endeavor patients have had at least two years of follow-up, none of whom have developed late stent thrombosis based on independent, pre-specified clinical trial protocol definitions for thrombosis.
Those in the 436-patient ENDEAVOR III trial are being followed out to five years. The clinical data reported at ACC as part of the study design indicate that the Endeavor stent continues to exhibit an excellent safety profile while delivering sustained efficacy and a low need for repeat procedures that is consistent with the overall Endeavor clinical program.
At two years, the rate of Major Adverse Cardiac Events — a composite safety measure of death, repeat procedures and myocardial infarction (MI) — was reported to be 9.3 percent for Endeavor and 11.6 percent for the Cypher stent also studied in the ENDEAVOR III trial (p = 0.47). There was no statistically significant difference in the need for repeat procedures, or Target Lesion Revascularization (7.0 percent and 4.5 percent for Endeavor and Cypher, respectively, p = 0.50), or all-cause mortality (1.6 percent for Endeavor and 4.5 percent for Cypher, p = 0.14). However, fewer patients experienced heart attacks (MI) when treated with the Endeavor stent (0.6 percent vs. 3.6 percent for Cypher, p = 0.04) and the combined rate of heart attack and death also was statistically significantly lower among patients randomized to the Endeavor stent (2.2 percent vs. 7.1 percent for Cypher, p = 0.013).
Confidence in Endeavor safety
Worldwide, Medtronic has approximately 2,100 Endeavor patients enrolled in its multiple clinical trials, and the growing volume of positive data and number of patients with long-term follow-up continues to reinforce the stent’s favorable safety and efficacy profile. The Endeavor stent is not yet approved for use in the United States.
“With two years of follow-up in nearly 1,300 patients and the volume of positive clinical data we’ve seen to date, we can continue to have confidence in Endeavor’s clinical performance,” said Martin Leon, M.D., principal investigator of the ENDEAVOR III clinical trial and Professor of Medicine at Columbia University School of Medicine. “As the Endeavor clinical program has matured, it has provided evidence that consistent and predictable patient outcomes are being sustained through time.”
Scott Ward, senior vice president at Medtronic and president of the Vascular business, added: “The Endeavor clinical program continues to generate strong cumulative evidence regarding Endeavor’s overall performance. Patients have been 99.7 percent free from overall stent thrombosis and we’ve seen no late stent thrombosis in our pooled clinical trials. In addition, Endeavor has demonstrated a sustained reduction in repeat procedures of 61 percent compared to the Medtronic Driver bare metal stent and Endeavor’s death/MI rates have been trending lower than bare metal stents.”
Medtronic will present additional long-term data on Endeavor in the coming months. At the EuroPCR meeting in May, Medtronic will provide updated four-year and three-year results from the ENDEAVOR I and ENDEAVOR II trials respectively, as well as new data on the next-generation Endeavor Resolute drug-eluting stent. Results from the ongoing ENDEAVOR IV trial, another large randomized trial (1,548 patients) evaluating Endeavor against the Taxus stent made by Boston Scientific, are expected to be presented in the fall.
The Endeavor stent is made of a cobalt alloy and has a unique modular architecture designed to enhance deliverability over standard bare metal stents. In addition to the proprietary drug compound Zotarolimus, the Endeavor stent is coated with phosphorylcholine (PC), a polymer designed to simulate the outside surface of a red blood cell and mimic the structure of the natural cell membrane.