BACKGROUND: Gender differences in the thrombotic and bleeding risk have been suggested to condition the benefits of antithrombotic therapies in Acute Coronary Syndrome (ACS) patients, and mainly among those undergoing percutaneous coronary interventions with drug eluting stents (DES). The impact of gender on the optimal duration of dual antiplatelet therapy (DAPT) in ACS patients is still unexplored and was, therefore, the aim of the present sub-study. METHODS: REDUCE was a prospective, multicenter, randomized investigator-initiated study designed to enroll 1500 ACS patients after treatment with the COMBO Dual Stent Therapy, based on a noninferiority design. Patients were randomized in a 1:1 fashion to either 3 or 12 months of DAPT. Primary study endpoint was a composite of all-cause mortality, myocardial infarction, definite/probable stent thrombosis (ST), stroke, target-vessel revascularization (TVR) and bleedings (BARC II, III, V) at 12 months. Secondary endpoints were cardiovascular mortality and the individual components of the primary endpoint within 24 months. RESULTS: From June 2014 to May 2016 300 women and 1196 men were included in the study. Among them, 43.7% of females and 51.9% of males were assigned to the 3 months DAPT treatment. Baseline characteristics were well matched between the two arms, with the exception of a lower rate of TIMI flow < 3 (p = 0.04), lower systolic blood pressure (p = 0.05) and use of spironolactone (p = 0.006) among women and a more advanced age (p = 0.05) among men receiving a short-term DAPT. At a mean follow-up of 525 (± 198) days, no difference in the primary endpoint was observed according to DAPT duration in both females [6.9% vs 5.9%, HR (95% CI) = 1.19 (0.48-2.9), p = 0.71] and males [8.2% vs 9%, HR (95% CI) = 0.92 (0.63-1.35), p = 0.67; p INT = 0.20]. Results were confirmed after correction for baseline differences [females: adjusted HR (95% CI) = 1.12 (0.45-2.78), p = 0.81; males: adjusted HR (95% CI) = 0.90 (0.61-1.32), p = 0.60]. Comparable rates of survival, thrombotic (MI, stent thrombosis, TVR, stroke) and bleeding events were observed with the two DAPT strategies, with no impact of gender. CONCLUSIONS: The present study shows that among ACS patients randomized in the REDUCE trial, a 3 months DAPT strategy offers comparable results as compared to a standard 12 months DAPT at 2-years follow-up in both male and female gender.