November 5, 2019
Five-Year Results From ABSORB BTK Trial Presented
November 6, 2019—The 5-year results of the ABSORB BTK trial—a prospective, nonrandomized, single-center study evaluating a novel bioresorbable, drug-eluting scaffold for the treatment of peripheral artery disease below the knee—were presented by Ramon L. Varcoe, MBBS, MS, PhD, during a late-breaking clinical trial session at VIVA 2019, the Vascular InterVentional Advances meeting held November 4–7 in Las Vegas, Nevada. Prof. Varcoe is Associate Professor of Vascular Surgery at the University of New South Wales in Sydney, Australia.
The ABSORB BTK trial enrolled 48 patients who fulfilled the inclusion criteria (72.7% with critical limb ischemia). A total of 71 everolimus-eluting bioresorbable vascular scaffolds (Abbott) were used to treat 55 limbs across the trial patients. Most scaffolds were implanted in arteries of the proximal area of the calf, and the mean lesion length was 20.1 mm (range, 5–50 mm). The procedural and technical success was 100%.
According to the late-breaking trial summary, over the 5-year follow-up period, there was a 38% mortality rate, all due to causes unrelated to the procedure or study device; 95% of patients had sustained clinical improvement. Complete wound healing occurred in 90% of those treated for tissue loss, with no major amputations and a limb salvage rate of 100%. Using Kaplan-Meier estimates at 12, 36, and 60 months, primary patency (defined as freedom from peak systolic velocity ratio > 2.0 or target vessel occlusion) was 89.2%, 80.3%, 72.9%; freedom from clinically driven target lesion revascularization rates were 97.2%, 90.7%, 90.7%, respectively. No late or very late scaffold thromboses were observed.
Prof. Varcoe concluded by announcing that a new multicenter international randomized trial (LIFE-BTK) evaluating the Esprit bioresorbable stent versus percutaneous transluminal angioplasty below the knee is in preparation. Its leadership will include Prof. Varcoe; Sahil Parikh, MD, FACC, FSCAI; and Brian DeRubertis, MD, FACS.