Original Title: Polymer-Free Biolimus A9-Coated Stents in the Treatment of De Novo Coronary Lesions4- and 12-Month Angiographic Follow-Up and Final 5-Year Clinical Outcomes of the Prospective, Multicenter BioFreedom FIM Clinical Trial CME. Reference: Ricardo A. Costa et al. J Am Coll Cardiol Intv. 2016;9(1):51-64.

The purpose of this study was to assess the efficacy and long term outcomes of the new polymer free biolimus coated stent in patients with de novo coronary lesions.

The BioFreedom stent incorporates a low profile stainless steel scaffold with a surface that has been modified to create a selective abluminal micro structure that allows the adhesion and further release of Biolimus A9 (Biosensors Europe SA, Morges, Switzerland).

A total of 182 patients were randomized 1:1:1 to the new polymer free stent with a standard dose of the drug vs. the same stent with a low dose vs. the first generation paclitaxel eluting stent, in 4 cities, in Germany.

Baseline and procedural characteristics were well balanced between the 3 groups.

At 4 month angiographic follow up, there was significantly lower lumen loss with the standard and lower doses biolimus releasing stents vs. the paclitaxel eluting stent (0.08 y 0.12 mm vs. 0.37 mm, respectively; p < 0.0001 for the biolimus eluting stent with standard dose vs. paclitaxel eluting stent, and p=0.002 for the biolimus eluting stent with low dose vs. paclitaxel eluting stent).

At 12 months, late lumen loss (primary end point) was 0.17 mm for the biolimus eluting with standard dose vs. 0.35 mm for the paclitaxel ES, reaching both non inferiority (p=0.001) and superiority (p=0.11). The low dose biolimus eluting stent did not reach non inferiority compared to the paclitaxel eluting stent.

At 5 years, there were no significant differences in major cardiac events between the three groups (23.8%, 26.4% and 20.3%) or the ischemia driven target lesion revascularization (10.8%, 13.4% and 10.2%). There were no reports of definite / probable thrombosis in the study.

Conclusion
The polymer free biolimus eluting stent with standard dose showed non inferiority compared to the first generation paclitaxel eluting stent in terms of late lumen loss at 12 months but not for the low dose biolimus eluting stent. At 5 years clinical events were similar and in low numbers, with no definite/ probable thrombosis events.