Thin- versus thick-strut polymer-free biolimus-eluting stents: the BioFreedom QCA randomised trial

The BioFreedom drug-coated stent with a stainless steel platform (BF-SS) has been demonstrated to be efficacious in patients at high bleeding risk and receiv-ing only one-month dual antiplatelet therapy. The aim of this study was to evaluate the efficacy of the new BioFreedom Ultra drug-coated stent with a thin-strut cobalt-chromium platform (BF-CoCr) compared to the BF-SS in an all-comers population undergoing percutaneous coronary intervention (PCI). This was a prospective, multicentre, non-inferiority trial. The primary endpoint was in-stent late lumen loss (LLL) as determined by quantitative coronary angiography at nine-month follow-up. Clinical evaluation was performed at one year. A total of 200 patients were randomised (1:1) to either the BF-CoCr or the BF-SS stent at eight centres in Spain and Denmark. Baseline clinical and lesion characteristics were similar between the groups. Mean age was 66 years and 23% were female. The mean number of stents implanted per patient was 1.5. At nine-month follow-up, mean in-stent LLL was 0.34±0.49 mm in the BF-CoCr group versus 0.29±0.37 mm in the BF-SS group, p=0.005 for non-inferiority. At one year, target lesion failure was similar between the groups (7.3% in BF-CoCr vs 9.3% in the BF-SS group; p=0.60). The BF-CoCr was non-inferior to the BF-SS in terms of in-stent LLL at nine months. Larger studies powered for clinical endpoints are warranted to compare the efficacy of this new platform with currently available DES.