Blog #11

Stone, G. W. et al. “Randomized comparison of everolimus-eluting and paclitaxel-eluting stents: two-year clinical follow-up from the Clinical Evaluation of the Xience V Everolimus Eluting Coronary Stent System in the Treatment of Patients with de novo Native Coronary Artery Lesions (SPIRIT) III trial.” Epubmed February 10 (2009): 119(5): 680-6.

http://www.ncbi.nlm.nih.gov/pubmed/19171853?ordinalpos=&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.SmartSearch&log$=citationsensor

Nikolosky E, et al. “SPIRIT IV trial design: a large-scale randomized comparison of everolimus-eluting stents and paclitazel-eluting stents in patients with coronary artery disease.” American Heart Journal. October 2009: 520-526.

http://www.ncbi.nlm.nih.gov/pubmed/19781409?ordinalpos=&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.SmartSearch&log$=citationsensor

As our understanding and usage of drug-eluting stents continues to improve and advance, better treatments for coronary artery lesions are surfacing. In a recent (2009) randomized comparison in the treatment of patients with de novo native coronary artery lesions known as the SPIRIT III trial, it was found that everolimus-eluting stents show better results than paclitaxel-eluting stents. Paclitaxel-eluting stents (PES) are currently widely used, but one could safely say that these will soon be replaced by everolimus-eluting stents (EES). Paclitaxel is a mitotic inhibitor used in cancer therapy, whereas everolimus, like sirolimus and zotolimus, works as an mTOR (mammalian target of rapamycin) inhibitor and is used as an immunosuppressant to prevent rejection of organ transplants. The comparison study found that patients treated with EES experienced statistically significant reduction in angiographic in-segment late loss at eight months, a surrogate marker for restenosis, and noninferior rates of target vessel failure (cardiac death, myocardial infarction, or target vessel revascularization) at 1 year. Additionally, these patients experienced significantly improved event-free survival at a 2-year follow-up in the SPIRIT III trial. Although further study is needed, the trends show that EES-treated patients are experiencing fewer stent thrombosis episodes after six months than PES-treated patients.

In a follow-up article on the comparison of EES and PES in the SPIRIT III trial, researchers argue that the trial was not powered for superiority for clinical end points and the routine performance of angiographic follow-up may have artificially exaggerated the absolute benefits of EES. Therefore, an additional SPIRIT IV trial is currently underway to find more conclusive evidence on the subject. This trial is a prospective, active-controlled, single-blinded, multicenter clinical trial with 3690 patients with native coronary artery disease. We already assume that EES is superior to PES, but we should not base our knowledge on under supported evidence. Due to its size and controls, the results of this study will more aptly determine the efficacy and side effects of everolimus and paclitaxel-eluting stents and further define their clinical utilities.