ABSORB IV: BVS noninferior to metallic DES if implanted optimally

Gregg W. Stone

SAN DIEGO — A polymeric bioresorbable vascular scaffold when implanted properly in the optimal patient population was noninferior to a metallic drug-eluting stent regarding target lesion failure and angina at 30 days and 1 year, according to data presented at TCT 2018.

Device thrombosis at 1 year was numerically but not significantly higher in patients with stable CAD or ACS assigned the BVS (Absorb, Abbott Vascular) vs. the everolimus-eluting stent (Xience, Abbott Vascular) in the ABSORB IV trial.

“This is the largest randomized head-to-head trial of Absorb vs. Xience,” Gregg W. Stone, MD, director of cardiovascular research and education at the Center for Interventional Vascular Therapy at NewYork-Presbyterian/Columbia University Irving Medical Center, said during the press conference.

Researchers analyzed data from 2,604 patients who underwent PCI for stable CAD or ACS at 147 sites. The findings were simultaneously published in The Lancet.

The intervention was performed in up to three de novo native coronary artery lesions in up to two epicardial coronary arteries. Lesions in these patients were at least 24 mm long and the reference vessel diameter was between 2.5 mm and 3.75 mm. Those with biomarker-positive ACS, planned three-lesion treatment or angiographic thrombus were also included in the trial.

In previous ABSORB trials, some patients had a reference vessel diameter of 2.25 mm or smaller, which is smaller than intended for the BVS, and some implantations were done with suboptimal techniques, but ABSORB IV was designed to show the performance of the BVS in patients with the proper reference vessel diameter implanted with optimal techniques, such as postdilatation with a noncompliant balloon, according to the researchers.

“There are some unique things about this trial,” Stone said during the press conference. “For the first time, we promoted enrollment of biomarker-positive non-STEMI and STEMI. We enrolled up to three target lesions, so we actually expanded the number of lesions, although most patients enrolled had just one lesion.”

Patients were assigned the BVS (n = 1,296; mean age, 63 years; 72% men) or the EES (n = 1,308; mean age, 62 years; 72% men).

Follow-up was conducted at 30 days, 90 days, 180 days, 270 days, 1 year and annually thereafter, where patients were asked about the presence and severity of interim clinical events, presence and severity of angina or anginal-equivalent symptoms and the use of CV medication. Quality of life was assessed with the Seattle Angina Questionnaire-7 form and the EuroQoL 5D survey.

The primary endpoint was TLF at 30 days, defined as a composite of target vessel MI, cardiac death or ischemia-driven target lesion revascularization, with a prespecified margin of 2.9% for risk difference. Major secondary endpoints were rates of TLF and adjudicated angina at 1 year.

Non-ABSORB III-like characteristics were seen in 26% of patients, and 24% of patients had biomarker-positive ACS. Of the 2,893 lesions that were treated, 3% of those had a diameter of less than 2.25 mm.

At 30 days, TLF occurred in 5% of patients assigned the BVS vs. 3.7% assigned the EES (risk difference = 1.3%; upper 97.5% confidence limit, 2.89; P for noninferiority = .0244). At 1 year, this outcome was seen in 7.8% in the BVS group compared with 6.4% in the EES group (risk difference = 1.4%; upper 97.5% confidence limit, 3.4; P for noninferiority = .0006).

Angina at 1 year occurred in 20.3% of patients assigned the BVS vs. 20.5% of those assigned the EES (risk difference = –0.3%; 95% CI, –3.4 to 2.9; P for noninferiority = .0008; P for superiority = .8603).

At 1 year, device thrombosis occurred in 0.7% of patients in the BVS group vs. 0.3% in the EES group (P = .1586).

“These data, although a little better, but consistent with the earlier ABSORB trials, emphasize the need for further advancements in device technology and improvements in technique such as routine intravascular imaging to further improve the early safety profile of BVS if the benefits of late scaffold bioresorption are to be realized,” Stone said during the press conference. – by Darlene Dobkowski

References:

Stone GW, et al. Late-Breaking Trials 5. Presented at: TCT Scientific Symposium; Sept. 21-25, 2018; San Diego.

Stone GW, et al. Lancet. 2018;doi:10.1016/S0140-6736(18)32283-9.

Disclosures: The trial was funded by Abbott Vascular. Stone reports he received consultant fees from Ablative Solutions, Claret, HeartFlow, Gore, Matrizyme, Miracor, Neovasc, Reva, Robocath, Shockwave, TherOx, V-wave, Valfix and Vascular Dynamics; holds equity/options in Ancora, Aria, Biostar family of funds, Cagent, Caliber, MedFocus family of funds, Qool Therapeutics and SpectraWave; and his employer, Columbia University, receives royalties from Abbott for the sale of the MitraClip. Please see the study for all other authors’ relevant financial disclosures.