Biodegradable polymer versus permanent polymer drug-eluting stents and everolimus- versus sirolimus-eluting stents in patients with coronary artery disease: 3-year outcomes from a randomized clinical trial

Objectives: The aim of this study was to compare the 3-year efficacy and safety of biodegradable polymer with permanent polymer stents and of everolimus-eluting stents (EES) with sirolimus-eluting stents (SES). Background: Biodegradable polymer drug-eluting stents (DES) offer potential for enhanced late outcomes in comparison with permanent polymer stents. In addition, there is increasing interest in the comparison of EES (Xience, Abbott Vascular, Abbott Park, Illinois) versus SES (Cypher, Cordis Corporation, Miami Lakes, Florida). Methods: The ISAR-TEST 4 (Intracoronary Stenting and Angiographic Results: Test Efficacy of 3 Limus-Eluting Stents-4) was a randomized clinical trial with broad inclusion criteria, enrolling 2,603 patients at 2 clinics in Munich, Germany. Patients were randomized to either biodegradable polymer (n = 1,299) or permanent polymer stents (n = 1,304); patients treated with permanent polymer stents were randomly allocated to EES (n = 652) or SES (n = 652). The primary endpoint was the composite of cardiac death, target vessel-related myocardial infarction, or target lesion revascularization. Results: Clinical events continued to accrue at a low rate out to 3 years in all groups. Overall, there was no significant difference between biodegradable polymer and permanent polymer DES with regard to the primary endpoint (20.1% vs. 20.9%, hazard ratio [HR]: 0.95, 95% confidence interval [CI]: 0.80 to 1.13; p = 0.59). Rates of definite/probable stent thrombosis were also similar in both groups (1.2% vs. 1.7%, respectively; HR: 0.71, 95% CI: 0.37 to 1.39; p = 0.32). In patients treated with permanent polymer stents, EES were comparable to SES with regard to the primary endpoint (19.6% vs. 22.2%, respectively; HR: 0.87, 95% CI: 0.68 to 1.11; p = 0.26) as well as definite/probable stent thrombosis (1.4% vs. 1.9%, HR: 0.75, 95% CI: 0.32 to 1.78; p = 0.51). Conclusions: Biodegradable polymer and permanent polymer DES are associated with similar clinical outcomes at 3 years. In addition, EES are comparable to SES in terms of overall clinical efficacy and safety. (Intracoronary Stenting and Angiographic Results: Test Efficacy of 3 Limus-Eluting STents [ISAR-TEST 4]: Prospective, Randomized Trial of 3-limus Agent-eluting Stents With Different Polymer Coatings; NCT00598676)