October 14, 2020
Pilot Randomized PROSPECT ABSORB Trial Evaluates Safety of PCI of Nonflow-Limiting Vulnerable Plaques
October 14, 2020—New data from PROSPECT ABSORB, a pilot randomized trial of percutaneous coronary intervention (PCI) of nonflow-limiting vulnerable plaques in native coronary arteries, found that PCI was safe, substantially enlarged follow-up lumen areas, and was associated with favorable long-term clinical outcomes.
The PROSPECT ABSORB study was an investigator-sponsored, multicenter, single-blinded, active-treatment-controlled randomized trial that was embedded into the PROSPECT II natural history study. PROSPECT II enrolled 902 patients at 16 sites between June 10, 2014 and December 20, 2017. Gregg W. Stone, MD, and David Erlinge, MD, served as study co-chairs.
The findings were reported at TCT Connect, the 32nd annual Transcatheter Cardiovascular Therapeutics scientific symposium of the Cardiovascular Research Foundation (CRF) held online October 14–18, 2020. The findings were published simultaneously online ahead of print by Drs. Stone and Erlinge, et al in Journal of the American College of Cardiology.
As summarized in the TCT announcement, three-vessel imaging was performed with a combination near-infrared spectroscopy and intravascular ultrasound (NIRS-IVUS) intracoronary imaging catheter after successful PCI of all flow-limiting coronary lesions in 898 patients presenting with myocardial infarction (MI). Of those 898 patients, 182 patients with an angiographically nonobstructive stenosis not intended for PCI but with IVUS plaque burden ≥ 65% were randomized to treatment of the lesion with a bioresorbable vascular scaffold (BVS) plus guideline-directed medical therapy (GDMT; n = 93) versus GDMT alone (n = 89).
The primary effectiveness endpoint was the IVUS-derived minimum lumen area (MLA) at protocol-driven 25-month follow-up.
The primary (nonpowered) safety endpoint was target lesion failure (TLF; composite of cardiac death, target vessel-related MI, or clinically driven target lesion revascularization) at 24 months. Angiographic follow-up at 25 months was completed in 167 patients (91.8%), and median clinical follow-up was 4.1 years.
The investigators reported the following:
- Follow-up MLA in BVS-treated lesions was 6.9 ± 2.6 mm2 compared with 3.0 ± 1.0 mm2 in GDMT alone-treated lesions (least square means difference, 3.9 mm2; 95% CI, 3.3-4.5; P < .0001).
- TLF at 24 months occurred in similar rates of BVS-treated and GDMT alone-treated patients (4.3% vs 4.5%; P = .96).
- The secondary (nonpowered) clinical effectiveness endpoint of randomized lesion-related MACE to the time of latest follow-up occurred in 4.3% of BVS-treated patients versus 10.7% of GDMT alone-treated patients (odds ratio, 0.38; 95% CI, 0.11-1.28; P = .12).
“The results from PROSPECT ABSORB indicate that PCI of vulnerable plaques may safely enlarge the lumen and change the structure of the lesion, theoretically reducing its propensity for thrombosis and progression,” commented Dr. Stone in the TCT press release. “The favorable randomized lesion-related MACE rates observed after BVS treatment compared with medical therapy alone warrants the performance of an adequately powered randomized trial to determine whether PCI treatment of vulnerable plaques improves patient outcomes.”