POLYMER-FREE amphilimus-eluting stents (AES) were found to be non-inferior to biodegradable-polymer everolimus-eluting stents (EES) at one-year follow-up in patients undergoing percutaneous coronary intervention (PCI), though with a higher incidence of early stent thrombosis.
Percutaneous coronary intervention (PCI) is a common procedure for patients with coronary artery disease, often requiring the implantation of drug-eluting stents to maintain vessel patency. While biodegradable-polymer everolimus-eluting stents (EES) are widely used, polymer-free amphilimus-eluting stents (AES) have been proposed as an alternative to reduce long-term polymer-related complications. This study aimed to assess whether polymer-free AES are as effective and safe as biodegradable-polymer EES in an all-comer PCI population.
A randomised, assessor-blind, non-inferiority trial was conducted across 14 hospitals in Italy, enrolling 2,107 patients with 3,042 coronary lesions between January 2020 and June 2022. Participants were randomly assigned to receive either polymer-free AES (1,051 patients) or biodegradable-polymer EES (1,056 patients). The primary endpoint was a device-oriented composite of cardiovascular death, target vessel myocardial infarction, or target lesion revascularisation at one year. At follow-up, the primary endpoint occurred in 8.2% of patients with polymer-free AES compared to 7.2% with biodegradable-polymer EES (risk difference 1%, upper 95% confidence interval [CI] limit 2.9%; p for non-inferiority=0.041). There was no significant difference in individual components of the primary endpoint; however, definite or probable stent thrombosis was more frequent in the polymer-free AES group (1.0% vs 0.3%; hazard ratio 3.72, 95% CI: 1.04–13.33; p=0.044), primarily due to an increased risk within the first 30 days post-procedure.
These findings suggest that polymer-free AES are a viable alternative to biodegradable-polymer EES in terms of overall clinical outcomes at one year. However, the increased early stent thrombosis risk raises concerns regarding short-term safety, which may influence clinical decision-making. Further studies are warranted to explore strategies for mitigating early thrombosis risk and to assess longer-term outcomes. Clinicians should weigh the potential benefits of polymer-free stents against the observed early risk when selecting devices for PCI patients.
Katrina Thornber, EMJ
Reference
Piccolo R et al. Polymer-free versus biodegradable-polymer drug-eluting stent in patients undergoing percutaneous coronary intervention: an assessor-blind, non-inferiority, randomised controlled trial. 2025;21:58-72.
