The aim was to compare in a noninferiority trial the efficacy and safety of 2 contemporary drug-eluting stents (DESs): a novel, durable polymer-coated stent versus an established bioabsorbable polymer-coated stent.

The BIONYX trial (ClinicalTrials.gov-no.NCT02508714) is an investigator-initiated, prospective, randomized, patient- and assessor-blinded, international, multicenter study in all-comer patients with all types of clinical syndromes and lesions who require percutaneous coronary interventions with DES. Patients at 7 study sites in the Netherlands, Belgium, and Israel were randomly assigned (1:1, stratified for gender and diabetes mellitus) to treatment with the novel, zotarolimus-eluting, durable polymer-coated Resolute Onyx stent that has a radiopaque, thin-strut, CoreWire stent platform versus the sirolimus-eluting, bioresorbable polymer-coated Orsiro stent (reference device) that has a very thin-strut, cobalt-chromium stent backbone. The primary end point is the 1-year incidence of the composite clinical end point target vessel failure consisting of cardiac death, target vessel–related myocardial infarction, or clinically indicated target vessel revascularization. A power calculation, assuming a target vessel failure rate of 6.0% (noninferiority margin 2.5%), revealed that 2,470 study patients would give the study 80% power (α level 5%), allowing for up to 3% loss to follow-up. The first patient was enrolled on October 7, 2015; on December 23, 2016, the last patient entered the study.

BIONYX is a large-scale, prospective, randomized, international, multicenter trial comparing a novel DES with durable coating versus a reference DES with biodegradable coating in all-comers. The study is the first randomized assessment of the Resolute Onyx stent, which is an often-used DES outside the United States.