This article is more than 5 years old. Information may no longer be current.
Two studies demonstrate noninferiority of bioresorbable vascular scaffold system
Click Here to Manage Email Alerts
LONDON — In two studies of an everolimus-eluting bioresorbable vascular scaffold system, the technology was noninferior to metallic drug-eluting stents, according to presentations from the European Society of Cardiology Congress.
Results from the TROFI II study indicated that the bioresorbable system (Absorb, Abbott Vascular) was noninferior to an everolimus-eluting stent (Xience, Abbott Vascular), and findings from the ABSORB Japan study showed the bioresorbable system to be noninferior to cobalt chromium everolimus-eluting stents.
TROFI II
In TROFI II, Patrick W. Serruys, MD, PhD, and colleagues compared the arterial healing response of the bioresorbable system and the EES using optimal frequency domain imaging.
Vessel healing was evaluated with a score consisting of four components: intraluminal defect, malapposed and uncovered, uncovered but apposed, and malapposed but covered. A lower score was considered better, Serruys, emeritus professor of interventional cardiology at Imperial College, London, and Thoraxcenter, Erasmus University, Rotterdam, Netherlands, said here.
The researchers randomly assigned 191 patients with STEMI to receive either the bioresorbable system (n = 95) or the EES (n = 96). The primary endpoint was healing score at 6 months as determined by optimal frequency domain imaging.
The healing score for the bioresorbable system was noninferior and almost superior to that of the EES at 6 months (1.74 vs. 2.8; P for noninferiority < .001; P for superiority = .053), Serruys said.
“Frequency of malapposed and both malapposed and uncovered struts were lower in the Absorb arm, while there was no presence of intraluminal mass in both groups,” Serruys said at a press conference.
One patient in each group experienced in-segment binary restenosis (P = 1), while the groups differed with regard to in-device percent diameter stenosis (bioresorbable system, 18.3; EES, 14.5; P = .02), in-device late loss (bioresorbable system, 0.2 mm; EES, 0.08 mm; P = .02) and in-segment late loss (bioresorbable system, 0.16 mm; EES, 0.06 mm; P = .049), researchers found.
There were no clinical events at 6 months in the EES group and one in the bioresorbable group, a patient with subacute definite scaffold thrombosis, which led to MI and target lesion revascularization, Serruys said. He noted that 91.4% of patients in the bioresorbable group and 91.7% in the EES group were angina-free at 6 months.
ABSORB Japan
The ABSORB Japan trial, designed for regulatory approval in Japan, evaluated target lesion failure at 12 months in 400 patients with one or two de novo lesions. Researchers assigned patients to receive the bioresorbable system (n = 266) or a cobalt chromium EES (n = 134). The secondary endpoint was in-segment late lumen loss at 13 months.
At 12-months, the bioresorbable system was noninferior to EES in TLF, defined as cardiac death, MI in the target vessel or ischemia-driven TLR (bioresorbable system, 4.2%; EES, 3.8%; difference, 0.39%; upper one-sided 95% confidence limit, 3.95%; P for noninferiority < .0001), Takeshi Kimura, MD, said at the press conference. Stent/scaffold thrombosis rates were 1.5% in each group (P = 1) and TLR rates were 1.1% in the bioresorbable group and 1.5% in the EES group (P = 1), he said.
At 13 months, in-segment late lumen loss was 0.13 mm in the bioresorbable group and 0.12 mm in the EES group (difference, 0.1 mm; upper one-sided 95% confidence limit, 0.07; P for noninferiority < .0001).
“These positive results lay a solid foundation for continued evaluation of long-term outcomes in patients undergoing [PCI] with Absorb BVS,” Kimura, from the department of cardiovascular medicine at Kyoto University Hospital, Kyoto, Japan, said.
The ABSORB Japan results were simultaneously published in the European Heart Journal. – by Erik Swain
References:
Kimura T, et al.
Serruys, PW, et al. Hot Line VI: Coronary Artery Disease. Both presented at: European Society of Cardiology Congress; Aug. 29-Sept. 2; London.
Disclosures: TROFI II was sponsored by the European Cardiovascular Research Institute with grants from Abbott Vascular and Terumo. Serruys reports serving on an advisory board for Abbott Vascular. ABSORB Japan was funded by Abbott Vascular. Kimura reports serving on advisory boards for Abbott Vascular and Abbott Vascular Japan.