von Birgelen C, et al. - Researchers conducted the first randomized clinical trial to assess the effectiveness and safety of the Resolute Onyx stent vs the Orsiro stent, which has ultrathin cobalt–chromium struts. At 1-year follow-up in allcomers, the Resolute Onyx stent was non-inferior to Orsiro for a combined safety and efficacy endpoint. The low event rate in the Resolute Onyx group and the Orsiro group indicates the safety of both stents.

Methods

• For this investigation, researchers conducted an investigator-initiated, assessor-blinded and patient-blinded, randomized non-inferiority trial in an allcomers population at seven independently monitored centers in Belgium, Israel, and the Netherlands.
• Eligibility criteria included participants who were 18 years or older and required percutaneous coronary intervention with drug-eluting stents.
• Members of the catheterization laboratory team used web-based computer-generated allocation sequences to randomly assign patients (1:1) to either the Resolute Onyx or the Orsiro stent after guide wire passage, with or without predilation.
• By sex and diabetes status, randomization was stratified.
• After that, patients and assessors were masked to allocated stents, but treating clinicians were not.
• Target vessel failure (a composite of cardiac death, target-vessel-related myocardial infarction, and target vessel revascularization) at 1 year was the primary endpoint, and was assessed by intention to treat (non-inferiority margin 2.5%) on the basis of outcomes adjudicated by an independent event committee.

Results

• Two thousand, five hundred sixteen subjects were selected, 2,488 of whom were included in the intention-to-treat analysis (28 withdrawals or screening failures) between October 7, 2015 and December 23, 2016.
• One thousand, two hundred forty-three study participants were assigned to the Resolute Onyx group, and 1,245 study participants were assigned to the Orsiro group.
• It was observed that 1,765 (70.9%) participants presented with acute coronary syndromes and 1,275 (51.2%) had myocardial infarctions.
• For 2,478 (99.6%) patients, 1-year follow-up was available.
• It was noted that the primary endpoint was met by 55 (4.5%) patients in the Resolute Onyx group and 58 (4.7%) in the Orsiro group.
• Thus, non-inferiority of Resolute Onyx to Orsiro was established (absolute risk difference -0.2% [95% CI -1.9 to 1.4]; upper limit of the one-sided 95% CI 1.1%; p _{non-inferiority}=0.0005).
• Findings revealed that definite or probable stent thrombosis occurred in one (0.1%) participant in the Resolute Onyx group and 9 (0.7%) in the Orsiro group (hazard ratio 0.11 [95% CI 0.01–0.87]; p=0.0112).