Final 3-Year Results Published for the SPIRIT Clinical Trials of Abbott Vascular's Xience V EES

September 18, 2013—George D. Dangas, MD, et al published the final 3-year results of the SPIRIT clinical trials program in the Journal of the American College of Cardiology (JACC): Cardiovascular Interventions (2013;6:914–922). The SPIRIT program is a clinical evaluation of the Xience V everolimus-eluting coronary stent system (EES; Abbott Vascular, Santa Clara, CA) for the treatment of patients with de novo native coronary artery lesions. This study sought to investigate whether the Xience V EES is superior to a paclitaxel-eluting stent (PES) with respect to long-term individual clinical outcomes.

The investigators concluded that in this large dataset with 3-year follow-up, coronary implantation of EES compared with PES resulted in reduced rates of all-cause mortality, myocardial infarction (MI), ischemia-driven target lesion revascularization, stent thrombosis, and target lesion failure.

According to the investigators, the background of the evaluations is that individual studies have indicated a clinical advantage of coronary EES compared with PES with respect to restenosis and the composite endpoint of major adverse cardiac events; however, these trials were not powered for superiority in low-frequency event rates and have reported limited data beyond 1-year follow-up.

As summarized in JACC: Cardiovascular Interventions, the investigators conducted a meta-analysis of the final 3-year results from the international SPIRIT II, III, and IV clinical trials. Individual patient data from 4,989 patients who were prospectively randomized to treatment with EES (n = 3,350) or PES (n = 1,639) were pooled for analysis.

The investigators reported that at 3-year follow-up, EES was superior to PES in reducing the following event rates: target lesion failure, 8.9% vs 12.5% (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.59–0.85; P = .0002); all-cause mortality, 3.2% vs 5.1% (HR, 0.65; 95% CI, 0.49–0.86; P = .003); MI, 3.2% vs 5.1% (HR, 0.64; 95% CI, 0.48–0.85; P = .002); cardiac death or MI, 4.4% vs 6.3% (HR, 0.7; 95% CI, 0.54–0.9; P = .005); ischemia-driven target lesion revascularization, 6% vs 8.2% (HR, 0.72; 95% CI, 0.58–0.9; P = .004); stent thrombosis, 0.7% vs 1.7% (HR, 0.45; 95% CI, 0.2– 0.78; P = .003); and major adverse cardiac events, 9.4% vs 13% (HR, 0.71; 95% CI, 0.6–0.85; P = .0002).

Additionally, no interaction was present between stent type and the 3-year relative rates of target lesion failure across a broad range of subgroups, with the exception of diabetes and vessel (left anterior descending vs other).

Further research is warranted to characterize possible interactions between stent type, diabetes, and vessel, advised the investigators in JACC: Cardiovascular Interventions.