Biofreedom Prospective Multicenter Observational Registry

Percutaneous coronary intervention (PCI) and related interventional cardiology field are rapidly growing in current era. First generation drug eluting stent (DES) needed long-term dual antiplatelet therapy (DAPT) for preventing future stent thrombosis. But, second generation DES showed better clinical outcomes in terms of target lesion revascularization and stent thrombosis. Later, polymer technology that was used to release drugs gradually improved. BASKET-PROVE II trial compared biodegradable polymer (BP) DES (Nobori, Terumo) with durable polymer DES (Xience Prime, Abbott Vascular) and bare metal stent (ProKinetik, Biotronik) for the safety and efficacy in 2-year follow-up. BP-DES showed 7.6% of event rates in composite endpoint including cardiac death, myocardial infarction (MI), clinically indicated target-vessel revascularization (TVR) which was non-inferior to DP-DES(6.8%) and superior to bare metal stent (12.7%). There were no statistical differences for the event rates of stent thrombosis, MI and cardiac death among three groups in 1-year follow-up. Biodegradable polymer has begun to emerge and suggested the possibility of shortening the duration of DAPT. LEEDERS-FREE trial was designed to confirm the safety and efficacy of polymer-free drug-coated stent (Biofreedom, Biosensors International Technologies, Singapore) compared to bare metal stent (Gazelle stent, Biosensors International Technologies, Singapore) in patients with high bleeding risk. During 390 days, drug coated stent showed significant superiority to bare metal stent for the safety composite endpoint (cardiac death, MI or stent thrombosis) (9.4% vs. 12.9%, P=0.0005). Clinically-driven target-lesion revascularization also showed significant differences between drug-coated stent (5.1%) and bare metal stent (9.8%) (P<0.001). This results provided new therapeutic options that DAPT duration could be shortened to 1 month in patients with high bleeding risk. The rate of cardiovascular events was relatively higher than second generation DES. However, this result should be carefully interpreted because the main purpose of LEADERS-FREE trial is to enroll high bleeding risk patients who are generally excluded in second generation DES studies. Additional studies are needed because there are limited clinical evidences for extending these findings of LEADERS-FREE trial to generalized patients who are eligible to PCI.

• Biofreedom drug-coated stent (Device): BioFreedom (Biosensors International Technologies, Singapore) is the only polymer- and carrier-free drug coated stent with Biolimus A9 in a selectively micro-structured abluminal surface. It is a stainless steel bare metal surface with 120 micron thick corrugated ring strut.

Primary outcomes

• Device-oriented composite end point (TLF) [12 months]: Composite of cardiac death, any myocardial infarction not clearly attributable to a nontarget vessel, and clinically indicated target-lesion revascularization

Secondary outcomes

• Patient-oriented composite end point [12 months]: Composite of any death, any myocardial infarction, and any revascularization
• Cardiac death [12 months]
• Non-cardiac death [12 months]
• Any myocardial infarction [12 months]
• Any myocardial infarction not clearly attributable to a non-target vessel [12 months]
• Any revascularization [12 months]
• Clinically indicated target-lesion revascularization [12 months]
• Clinically indicated target-vessel revascularization [12 months]
• ARC defined stent thrombosis [12 months]

Sex: All, ages: 19 Years to any

Inclusion Criteria:

* Subject with ≥ 19 years
* Subject implanted with Biofreedom DCS within 1 month
* Subject who decided to participation and signed informed consent

Exclusion Criteria:

* Known intolerance to heparin, aspirin, clopidogrel, biolimus, cobalt chromium or contrast media (Subject with hypersensitivity to contrast media controlled by steroid and pheniramine can be included this study, but subject with anaphylaxis to contrast media will be excluded).
* Pregnancy
* Woman who have a plan of pregnancy during study period
* Subject with life expectancy less than 12 months
* Subject with cardiogenic shock
* Subject treated with other drug-eluting stent (DES), bioresorbable vascular scaffold (BVS) or bare metal stent (BMS)
* Subject participating in other randomized controlled study with DES, BVS or BMS

• Junghan Yoon, MD, PhD, Study director, Yonsei University