Randomized, double-blind, multicenter study of the Endeavor zotarolimus-eluting phosphorylcholine encapsulated stent for treatment of native coronary artery lesions:: Clinical and angiographic results of the ENDEAVOR II trial

Background - The use of the Endeavor stent might reduce restenosis and stent thrombosis at 9 months. Methods and Results - Patients (n = 1197) treated for single coronary artery stenosis were enrolled in a prospective, randomized, double-blind study and randomly assigned to receive the Endeavor zotarolimus-eluting phosphorylcholine polymer - coated stent (n = 598) or the same bare metal stent but without the drug or the polymer coating (n = 599). The 2 groups were well matched in baseline characteristics. Diabetes was present in 20.1% of patients; the mean reference vessel diameter was 2.75 mm; and the mean lesion length was 14.2 mm. The primary end point of target vessel failure at 9 months was reduced from 15.1% with the bare metal stent to 7.9% with the Endeavor (P = 0.0001), and the rate of major adverse cardiac events was reduced from 14.4% with the bare metal stent to 7.3% with the Endeavor (P = 0.0001). Target lesion revascularization was 4.6% with Endeavor compared with 11.8% with the bare metal stent (P = 0.0001). The rate of stent thrombosis was 0.5% with the Endeavor, which was not significantly different from 1.2% with the bare metal stent. In 531 patients submitted to angiographic follow-up, late loss was reduced from 1.03 +/- 0.58 to 0.61 +/- 0.46 (P < 0.001) in stent and from 0.72 +/- 0.61 to 0.36 +/- 0.46 (P < 0.001) in segment. The rate of in-segment restenosis was reduced from 35.0% to 13.2% with Endeavor (P < 0.0001). There was no excessive edge stenosis, aneurysm formation, or late acquired malapposition by intravascular ultrasound imaging. Differences in clinical outcome were maintained at 12 and 24 months ( P < 0.0001). Conclusions - Compared with bare metal stents, the Endeavor stent is safe and reduces the rates of clinical and angiographic restenosis at 9, 12, and 24 months.