Comparison of a Novel Biodegradable Polymer Sirolimus-Eluting Stent With a Durable Polymer Everolimus-Eluting Stent 5-Year Outcomes of the Randomized BIOFLOW-II Trial

OBJECTIVES The authors aimed to compare long-term data of an ultrathin cobalt-chromium stent with passive silicon carbide coating and an active biodegradable polymer that releases sirolimus (O-SES) (Orsiro, BIOTRONIK, Bulach, Switzerland) with the durable polymer-based Xience Prime everolimus-eluting stent (X-EES) (Abbott Vascular, Santa Clara, California). BACKGROUND Biodegradable polymer stents have been developed aiming to overcome long-term detrimental effects of durable polymer stents, ultimately leaving a bare-metal stent in the vessel. METHODS This multicenter, assessor-blinded trial randomized 452 patients with 505 lesions to either O-SES or X-EES in a 2: 1 fashion. Endpoints at 5 years were target lesion failure (TLF), its components, and stent thrombosis. RESULTS TLF occurred in 10.4% (n = 30) of O-SES patients versus 12.7% (n = 19) of X-EES patients (p = 0.473), overall stent thrombosis occurred in 0.7% (n = 2) versus 2.8% (n = 4) (p = 0.088), and definite stent thrombosis in 0% versus 0.7% (n = 1) (p = 0.341). Post hoc analysis was performed in diabetic patients (n = 128) and vessels <= 2.75 mm (n = 259). In diabetic patients, the O-SES group had numerically more target lesion revascularizations (13.5% vs. 4.5%; p = 0.138), but fewer cardiac deaths (1.3% vs. 6.9%; p = 0.089) and stent thrombosis (0% vs. 6.9%; p = 0.039). In small vessels, the O-SES group had a significantly lower 5-year mortality (3.7% vs. 11.3%; p = 0.022). CONCLUSIONS At 5 years, the biodegradable polymer O-SES demonstrated low TLF rates comparable to the durable polymer X-EES, confirming its long-term safety and performance. Particularly encouraging is the absence of definite stent thrombosis. (c) 2018 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).