RECORD3 was a multicentre, phase III study designed to investigate the efficacy and safety of rivaroxaban – a novel, oral, once-daily, direct Factor Xa inhibitor – compared with subcutaneous enoxaparin for thromboprophylaxis in patients undergoing total knee arthroplasty (TKA). Patients scheduled to undergo TKA (N=2,531) were randomized to receive either rivaroxaban 10 mg once daily (initiated 6–8 hours after surgery) or enoxaparin 40 mg once daily (initiated the evening before surgery, then given 6–8 hours after surgery), and daily thereafter for 10–14 days. The primary efficacy outcome was the composite of any deep vein thrombosis (DVT; symptomatic or asymptomatic detected by mandatory, bilateral venography), non-fatal pulmonary embolism (PE) and all-cause mortality within 13–17 days after surgery. Rivaroxaban significantly reduced the incidence of the primary efficacy outcome compared with enoxaparin (9.6% vs 18.9%, respectively; p<
0.001; relative risk reduction [RRR] 49%). Rivaroxaban significantly reduced the incidence of major VTE (the composite of proximal DVT, non-fatal PE and VTE-related death) compared with enoxaparin (1.0% vs 2.6%, p=0.01; RRR 62%), and the incidence of symptomatic VTE (0.7% vs 2.0%, p=0.005; RRR 66%). The incidence of bleeding events was similar in both groups (major bleeding: 0.6% and 0.5% in the rivaroxaban and enoxaparin groups, respectively; any on-treatment bleeding: 4.9% and 4.8%, respectively; haemorrhagic wound complications [the composite of excessive wound haematoma and surgical-site bleeding]: 2.0% and 1.9%, respectively). There were no deaths or PEs in the rivaroxaban group during the treatment period, and two deaths and four PEs in the enoxaparin group. Rivaroxaban was significantly more effective than enoxaparin for the prevention of VTE after TKA, with a similar rate of bleeding. The oral, direct Factor Xa inhibitor rivaroxaban, given once daily as a fixed, unmonitored dose of 10 mg, has the potential to change clinical practice for thromboprophylaxis after TKA.