Randomized, double‐blind, multicenter study of the polymer‐based 17‐β estradiol‐eluting stent for treatment of native coronary artery lesions: Six‐month results of the ETHOS I trial

Abstract

The ETHOS I trial was the first in-human experience evaluating the safety and efficacy of two different release formulations of the 17-beta estradiol-eluting R-Stent versus uncoated control stents for the treatment of patients with single de novo native coronary lesions. Estrogens were reported to inhibit neointimal proliferation and to accelerate endothelial regeneration after coronary angioplasty and thus could be an ideal compound to deliver on a stent for the purpose of reducing in-stent restenosis. Ninety-five patients were randomized to receive a slow-release (n = 32) or the moderate release (n = 31) formulations or the bare metal stent (n = 32). The primary end point was the 6-month percent in-stent volume obstruction by intravascular ultrasound (IVUS). Diabetes was present in 29.5% of patients; the mean reference vessel diameter was 2.90 mm; and the mean lesion length was 13.5 mm. Primary endpoint, 6-month percent in-stent volume obstruction by IVUS, did not differ significantly between the 3 groups (31% +/- 14%, 33% +/- 11%, and 31% +/- 14%, P = 0.83). Secondary endpoints also did not differ significantly between the groups including 6-month rates of in-lesion binary angiographic restenosis (13.3%, 14.3%, and 12.5%, P = 0.98), in-stent late loss (0.82 +/- 0.49 mm, 0.86 +/- 0.53 mm, and 0.84 +/- 0.46 mm, P = 0.97), target lesion revascularization (12.5%, 6.9%, and 6.5%, P = 0.64), and major adverse cardiac events (18.8%, 10.3%, and 6.5%, P = 0.31). In this first-in-man randomized trial, the 17-beta estradiol-eluting R-Stent, in either slow- or moderate-release formulations, was well-tolerated, but showed no benefit for treatment of coronary lesions when compared to controls.