Long-term clinical and economic analysis of the Endeavor zotarolimus-eluting stent versus the cypher sirolimus-eluting stent: 3-year results from the ENDEAVOR III trial (Randomized Controlled Trial of the Medtronic Endeavor Drug [ABT-578] Eluting Coronary Stent System Versus the Cypher Sirolimus-Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions).

Objectives: The aim of this study was to evaluate clinical and economic outcomes for subjects receiving zotarolimus-eluting (ZES) (n = 323) versus sirolimus-eluting stents (SES) (n = 113) in the ENDEAVOR III (Randomized Controlled Trial of the Medtronic Endeavor Drug [ABT-578] Eluting Coronary Stent System Versus the Cypher Sirolimus-Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions) clinical trial.

Background: Although previous clinical trials have evaluated long-term clinical outcome for drug-eluting stents, none considered their economic implications.

Methods: We analyzed case report form information with quality-of-life adjustment and Medicare cost weights applied from secondary sources; compared differences in clinical outcomes, quality-adjusted survival, medical resource use, and medical costs; and evaluated cost-effectiveness through 3-year follow-up.

Results: The use of ZES versus SES reduced the 3-year rates/100 subjects of death or myocardial infarction (3.9 vs. 10.8; difference, -6.9; 95% confidence interval [CI]: -13.0 to 0.8; p = 0.028), with no difference in target vessel revascularization rates (17.9 vs. 12.2; difference, 5.7; 95% CI: -3.7 to 15.1; p = 0.23) but greater use of coronary artery bypass graft (CABG) surgery (3.5 vs. 0.0; difference 3.5; 95% CI: 1.3 to 5.7; p = 0.002). After discounting at 3% per annum, total medical costs for ZES versus SES were similar ($23,353 vs. $21,657; difference, $1,696; 95% CI: -$1,089 to $4,482, p = 0.23), and the 3-year cost-effectiveness ratio was $57,002/quality-adjusted life year.

Conclusions: Despite a reduction in death or myocardial infarction and no difference in total revascularizations, medical costs were not decreased due to increased CABG repeat revascularization procedures for subjects receiving ZES versus SES. If future trials observe similar differences, improved safety with no difference in medical costs, the use of ZES versus SES will be a clinically and economically attractive treatment strategy. (The Medtronic Endeavor III Drug Eluting Coronary Stent System Clinical Trial [ENDEAVOR III]; NCT00217256).