Six versus 12 months of dual antiplatelet therapy after implantation of biodegradable polymer sirolimus-eluting stent: Randomized substudy of the I-LOVE-IT 2 trial

Background - There are no reports on a large-scale randomized trial exploring optimal dual antiplatelet therapy (DAPT) duration after biodegradable polymer sirolimus-eluting stent implantation. We sought to report the outcomes of a randomized substudy of the prospective Evaluate Safety and Effectiveness of the Tivoli DES and the Firebird DES for Treatment of Coronary Revascularization (I-LOVE-IT 2) trial. Methods and Results - In the prospective noninferiority randomized I-LOVE-IT 2 trial, 1829 patients allocated to the biodegradable polymer sirolimus-eluting stent group were also randomized to receive either 6-month (n=909) or 12-month DAPT (n=920). The primary end points of this noninferiority substudy were 12-month target lesion failure (composite of cardiac death, target vessel myocardial infarction or clinically indicated target lesion revascularization), and the major secondary end points were 12-month net adverse clinical and cerebral events (composite of all-cause death, all myocardial infarction, stroke, or major bleeding [Bleeding Academic Research Consortium type ≥3]). The 12-month target lesion failure in 6-month DAPT group was comparable with the 12-month DAPT group (6.8% versus 5.9%; difference and 95% confidence interval, 0.87% [-1.37% to 3.11%], P for noninferiority=0.0065). Further follow-up at 18 months showed that incidence of target lesion failure and net adverse clinical and cerebral events were similar between the 2 groups (7.5% versus 6.3%, log-rank P=0.32; 7.8% versus 7.3%, log-rank P=0.60; respectively), as well as their individual end point components. Conclusions - This study indicated noninferiority in safety and efficacy of 6-month versus 12-month DAPT after implantation of a novel biodegradable polymer sirolimus-eluting stent.