We designed a large scale clinical trial to compare a novel thin strut , cobalt-chromium drug-eluting stent with silicon carbide-coating releasing sirolimus from a biodegradable polymer ( O-SES , Orsiro ; Biotronik , Blach , Switzerland ) with the durable polymer-based Xience Prime/Xpedition everolimus-eluting stent ( EES ) ( Xience Prime/Xpedition stent , Abbott Vascular , IL ) in an all-comers patient population .