Three-year EXCEL Data Evaluate Abbott Vascular's EES in Left Main CAD

October 31, 2016—Three-year results from the EXCEL trial were presented at TCT 2016, the 28th annual Transcatheter Cardiovascular Therapeutics scientific symposium in Washington, DC, and simultaneously published online ahead of print by Gregg W. Stone, MD, et al in The New England Journal of Medicine.

EXCEL is a large-scale randomized trial examining percutaneous coronary intervention (PCI) versus coronary artery bypass graft surgery (CABG) in patients with left main coronary artery disease (CAD) and low-intermediate SYNTAX score. The EXCEL trial was funded by Abbott Vascular and used the company’s Xience Prime EES, Xience V EES, Xience Xpedition EES, or Xience Pro EES (used only outside the United States) to compare PCI and CABG.

The EXCEL investigators found that there was no significant difference in 3-year outcomes between the two treatments, with a reduction in 30-day major adverse events with PCI.

Dr. Stone, the trial's lead investigator, commented in the TCT announcement, “The historical gold standard therapy for left main CAD has been open heart surgery with CABG. However, improved outcomes with the newest generation of drug-eluting stents allows a less invasive approach to complex coronary artery disease for many patients.” He continued, “EXCEL is the first large-scale study to examine whether patients with left main CAD and low or intermediate CAD complexity can be safely treated with everolimus-eluting stents, which have been associated with low rates of stent thrombosis, rather than CABG.”

As summarized in the TCT press release, the EXCEL study recruited patients with left main CAD at 126 sites in 17 countries between September 2010 and March 2014. The investigators enrolled 2,905 patients, including 1,905 randomized and 1,000 registry patients. Eligible patients (n = 1,905) with left main CAD and low or intermediate CAD complexity (SYNTAX score ≤ 32) were randomized to revascularization with fluoropolymer-based cobalt-chromium everolimus-eluting stents (EES; n = 948) or CABG (n = 957).

The primary endpoint was the 3-year composite rate of death, stroke, or myocardial infarction (MI), powered for noninferiority testing. Major secondary outcomes included this endpoint at 30 days, and the composite rate of death, stroke, MI, or ischemia-driven revascularization at 3 years.

At 3 years, the primary endpoint of death, stroke, or MI occurred in 15.4% of EES patients and 14.7% of CABG patients (difference = 0.7%; upper 97.5% confidence limit, 4%; P_{noninferiority} = .018; hazard ratio, 1.0; 95% confidence interval, 0.79, 1.26; P_superiority = .98). The secondary endpoint of death, stroke, or MI at 30 days occurred in 4.9% of EES patients and 7.9% of CABG patients (P_superiority = .008). Death, stroke, MI or ischemia-driven revascularization at 3 years occurred in 23.1% of EES patients and 19.1% of CABG patients (P_{noninferiority} = .01; P_superiority = .1).

The data showed that patients treated with PCI rather than CABG had fewer MIs, and less bleeding, infections, arrhythmias, and renal failure within 30 days, although more repeat revascularization procedures at 3 years. Fewer patients developed definite stent thrombosis after PCI than symptomatic graft occlusion after PCI at 30 days and 3 years.

Dr. Stone concluded, “The 3-year follow-up results from EXCEL suggest that PCI with EES is an acceptable or even preferred alternative to CABG in selected patients with left main CAD. Longer-term follow-up is needed to examine whether additional differences between the two treatments emerge over time.”