ABSORB III: Bioresorbable scaffold noninferior to cobalt-chromium stent

SAN FRANCISCO — An everolimus-eluting bioresorbable vascular scaffold was noninferior to a cobalt-chromium everolimus-eluting stent for target lesion failure in patients with noncomplex obstructive CAD at 1 year in the ABSORB III trial.

Perspective from Sanjit S. Jolly, MD, MSc

“The primary endpoint for this trial has been met,” Dean J. Kereiakes, MD, FACC, medical director at The Christ Hospital Heart and Vascular Center/The Lindner Research Center, Cincinnati, and a member of the Cardiology Today’s Intervention Editorial Board, said in a presentation. “The [TLF] components of cardiac death, target vessel MI and ischemia-driven target lesion revascularization were not significantly different between the devices.”

Dean J. Kereiakes

The large-scale multicenter trial randomly assigned 2,008 patients with stable or unstable angina in a 2:1 ratio to an everolimus-eluting bioresorbable vascular scaffold (Absorb, Abbott Vascular; n = 1,322) or a cobalt-chromium everolimus-eluting stent (Xience, Abbott Vascular; n = 686).

The investigators sought TLF including CV death, target vessel MI or ischemia-driven TLR as primary endpoints, testing for noninferiority at a margin of 4.5 percentage points for risk difference as well as superiority.

At 1 year, 7.8% of patients with bioresorbable scaffold experienced TLF vs. 6.1% of patients with cobalt-chromium stent (difference, 1.7 percentage points; 95% CI, –0.5 to 3.9).

No differences were observed between the bioresorbable scaffold and cobalt-chromium stent groups for CV death (0.6% vs. 0.1%; P = .29), target vessel MI (6% vs. 4.6%; P = .18) or ischemia-driven TLR (3% vs. 2.5%; P = .5).

The powered secondary endpoints of angina, all revascularization and ischemia-driven TVR were similar between the devices. Similar results were seen for device thrombosis, occurring in 1.5% of patients with bioresorbable scaffold and 0.7% of patients with cobalt-chromium stent (P = .13).

“The ABSORB III trial has demonstrated safety and efficacy of Absorb [bioresorbable vascular scaffold] at 1 year in patients with stable CAD and stabilized ACS,” Kereiakes said. “Longer-term evaluation is ongoing to determine if Absorb improves late outcomes compared to Xience.” – by Allegra Tiver

References:

Ellis SG, et al. N Engl J Med. 2015;doi:10.1056/NEJMoa1509038.

Kereiakes DJ. Am Heart J. 2015;doi:10.1016/j.ahj.2015.07.013.

Kereiakes DJ. ABSORB III: A prospective randomized trial of an everolimus-eluting bioresorbable scaffold vs. an everolimus-eluting metallic stent in patients with coronary artery disease. Presented at: TCT 2015; Oct. 11-15, 2015; San Francisco.

Disclosure: Kereiakes reports multiple financial relationships in consulting, research and speakers capacities with Abbott Vascular, Boston Scientific Corp. and Svelte Medical Systems Inc., as well as using the off-label bioresorbable vascular scaffold to treat atherosclerosis.

Perspective

Sanjit S. Jolly, MD, MSc

ABSORB III was really a very important trial comparing the BVS platform to standard everolimus stents. People have been looking for this trial — first to show that that it’s as safe as standard metallic stents, and then to see whether it’s better.

The BVS met the noninferiority margin, and it achieved its primary objective. But the flip side is that as a clinician, BVS is much more challenging to deploy, and it’s much more expensive.

You would think the bar would be set much higher, that it needs to in some way reduce angina or improve other outcomes over time. We’ll just have to wait and see. We really need longer-term data and a larger sample size for BVS to change practice at the average physician level over the long term.

We are going to have more data from ABSORB IV and the combined data set from ABSORB III/IV. There is a hypothesis that the major benefit of BVS is going to happen beyond 1 year because the stent goes away. It’s a theoretical benefit. We have to really see whether that’s the case.

As a clinician, I really want to see that long-term data before switching my practice to BVS because we have been burnt in the past before, switching to newer devices without longer-term data.

Sanjit S. Jolly, MD, MSc

Associate professor of medicine and interventional cardiologist

McMaster University, Hamilton, Ontario, Canada

Disclosures: Jolly reports receiving grant support from the Canadian Institutes of Health Research, CANNeCTIN and Medtronic, and receiving personal fees from AstraZeneca and St. Jude Medical.