Objective To investigate the efficacy and safety of 6-month and 12-month oral dual-antiplatelet therapy This work was supported by the National Key Technology Research and Development Program in the Twelfth Five-year Plan of China (2011BAIl1B07) and the Military Clinical Key Technology and Development Program (2010gxjs001)(DAPT) on patients implanted with biodegradable polymer-coated and drug-eluted long stents (BP-DES).Methods In the I-LOVE-IT 2 trial,574 patients implanted with biodegradable polymer-coated and sirolimus-eluted long stent (BP-SES) (total stent length ≥50mm) were randomized to accepting either 6-month (n=270) or 12-month (n=304) DAPT.The primary endpoint of present study was 12-month target lesion failure (TLF),including cardiac death,target vessel myocardial infarction and clinically indicated target lesion revascularization (CI-TLR).The major secondary endpoint was 12-month net adverse clinical events (NACE),including all-causes of death,myocardial infarction,stroke,all revascularization (CI-TLR plus clinically indicated nontarget lesion revascularization) and bleeding.Results For the patients implanted with BP-SES of total stent length≥ 50mm,the total stent length was 73.0 ± 22.5mm and 69.8 ± 19.4mm in the 6-month DAPT group and 12-month group,respectively (P=0.07).No significant difference existed in the incidence of 12-month TLF between 6-month DAPT group and 12-month DAPT group (11.1％ vs.9.2％,P=0.47).The incidence of NACE was similar between the 2 groups (21.9％ vs.19.7％,P=0.57).The incidence of revascularization was lower in 12-month DAPT group (5.6％) than in 6-month DAPT group (11.1％,P=0.01).Furthermore,6-month landmark analysis showed that 12-month DAPT was associated with significantly lower risk of TLF (2.6％ vs.6.3％,P=0.03) at a cost of slightly increased risk of all bleeding events (1.6％ vs.0.7％,Log-rank P=0.32) between 6 and 12-months compared to 6-month DAPT.Conclusions In patients treated with BP-SES of total stent length ≥ 50mm,12-month DAPT have similar impacts on 12-month clinical outcomes except for all revascularization.However,12 months DAPT decreased the incidence of TLF and total revascularization between 6 months to 12 months after PCI.