Introduction: Venous thromboembolism (VTE) is a common, potentially fatal complication of major orthopaedic surgery. Although pharmacological thromboprophylaxis is recommended following total hip replacement (THR) for a minimum of 10 days, and up to 35 days, its extended use is not universally accepted – an effective, safe and convenient, oral anticoagulant would improve implementation of these recommendations. This trial compared short-term thromboprophylaxis using enoxaparin with extended thromboprophylaxis using rivaroxaban – a once-daily, oral, direct Factor Xa inhibitor – after THR, in the largest, prospective, randomized clinical trial conducted to date for the evaluation of the risk/benefit of extended prophylaxis.

Method: In this global, double-blind trial, 2509 patients undergoing THR were randomized to receive either subcutaneous enoxaparin 40 mg once daily (od), started the evening before surgery and continued for 10–14 days, followed by placebo until day 35±4 (short-term prophylaxis), or oral rivaroxaban 10 mg od, started 6–8 hours after surgery and continuing for 35±4 days (extended prophylaxis). Mandatory, bilateral venography was conducted on day 36±4. The primary efficacy endpoint was the composite of any deep vein thrombosis (DVT), non-fatal pulmonary embolism (PE), and all-cause mortality. The main secondary efficacy endpoint was major VTE (the composite of proximal DVT, non-fatal PE, and VTE-related death). Safety endpoints included the incidence of major and non-major bleeding.

Results: The incidence of the primary efficacy endpoint was significantly reduced with extended thromboprophylaxis with rivaroxaban compared with short-term enoxaparin (2.0% and 9.3%, respectively; p< 0.001; relative risk reduction [RRR] 79%), as was major VTE (0.6% versus 5.1%; p< 0.001; RRR 88%). The incidence of major bleeding was the same in both groups (0.1%). Non-major bleeding was reported in 6.5% of patients who received extended thromboprophylaxis with rivaroxaban and in 5.5% of those treated with short-term enoxaparin.

Conclusion: Extended duration thromboprophylaxis with rivaroxaban is both significantly more effective and adds no disadvantage, in terms of bleeding, when compared with short-term prophylaxis. These data suggest that extended thromboprophylaxis provides substantial benefits to patients undergoing THR and rivaroxaban provides a safe and effective option for this strategy.

Venous thromboembolism (VTE) is a potentially fatal complication after total hip replacement (THR) and may be associated with a considerable economic burden. In many centres, thromboprophylaxis using a subcutaneous (sc) anticoagulant in patients undergoing THR is restricted to 14 days or less. Rivaroxaban is a once-daily, oral, direct Factor Xa inhibitor in advanced clinical development for thromboprophylaxis after major orthopaedic surgery; it does not require monitoring or dose adjustment. In a phase III study, RECORD2, oral rivaroxaban 10 mg, given once daily for 35±4 days, significantly reduced the incidence of the primary endpoint (deep vein thrombosis, pulmonary embolism and all-cause mortality), compared with 40 mg sc enoxaparin, given for 14 days (2.0% vs 9.3%, respectively; relative risk reduction 79%; p< 0.001). The incidence of bleeding was low and similar in both groups, despite extended thromboprophylaxis with rivaroxaban. This analysis demonstrates the economic impact of extended thromboprophylaxis with oral rivaroxaban. The effect of rivaroxaban on healthcare costs was based on the primary efficacy results, and the associated reduced administration and monitoring costs, and includes non-drug costs only. The cost of symptomatic VTE was taken from published sources in the US and the UK 2007 NICE Guidelines. It was assumed that nurses spent 3 mins/day administering enoxaparin and training patients to self-inject for outpatient use. Hospital duration was 5 days. In the UK, full blood counts should be taken every 3 days when receiving enoxaparin. The total US health-care resource cost was $192/patient for enoxaparin and $39 for rivaroxaban (excluding drug costs). This saving of $153 was driven by reduced hospital costs associated with fewer VTEs when using rivaroxaban. In the UK, the total healthcare cost/patient was £44 with enoxaparin and £2 with rivaroxaban – savings driven equally by reduced hospitalization and monitoring costs with rivaroxaban prophylaxis. The different cost savings in the US and UK are due to higher US hospital costs. The costs of post-thrombotic syndrome (PTS) were excluded in this analysis. PTS has an estimated 5-year rate of 21% after asymptomatic VTE and 30% after symptomatic VTE, at a total cost/patient of more than $11,000 in the US and £4000 in the UK. Given the reduction in all VTE events with rivaroxaban, there are potential further healthcare cost savings due to reduced PTS. The RECORD2 study showed that extended prophylaxis (35 days) with rivaroxaban was significantly more effective than short-term enoxaparin (14 days) for the prevention of VTE, and was not associated with an increased risk of bleeding. This analysis illustrates an additional benefit of once-daily, oral rivaroxaban in the reduction in healthcare costs related to administration and monitoring.

Purpose: Venous thromboembolism (VTE) is a common, potentially fatal complication of major orthopaedic surgery. Pharmacologic thromboprophylaxis is recommended following total hip replacement (THR) for a minimum of 10 days, and up to 35 days. However, its extended use is not accepted universally – an effective, safe and convenient, oral anticoagulant would improve implementation of these recommendations. This study was conducted to compare short-term thromboprophylaxis with enoxaparin and extended thromboprophylaxis with the novel, oral, direct Factor Xa inhibitor rivaroxaban after THR. This was the largest, prospective, randomized clinical trial conducted to date for the evaluation of the risk/benefit of extended duration thromboprophylaxis.

Method: In this global, double-blind trial, 2509 patients undergoing THR were randomized to receive either subcutaneous enoxaparin 40 mg once daily (od), beginning the evening before surgery and continued for 10–14 days, followed by placebo until day 35±4 (short-term prophylaxis); or oral rivaroxaban 10 mg od beginning 6–8 hours after surgery and continuing for 35±4 days (extended prophylaxis). Mandatory, bilateral venography was conducted on day 36±4. The primary efficacy endpoint was the composite of any deep vein thrombosis (DVT), non-fatal pulmonary embolism (PE), and all-cause mortality. The main secondary efficacy endpoint was major VTE; the composite of proximal DVT, non-fatal PE, and VTE-related death. Safety endpoints included the incidence of major and non-major bleeding.

Results: Extended thromboprophylaxis with rivaroxaban significantly reduced the incidence of both the primary efficacy endpoint (2.0% versus 9.3%, respectively; p< 0.001; relative risk reduction [RRR] 79%) and major VTE (0.6% versus 5.1%, respectively; p< 0.001; RRR 88%), compared with short-term enoxaparin. The incidence of major bleeding was 0.1% in patients receiving either extended or short-term thromboprophylaxis. Non-major bleeding was reported in 6.5% of patients receiving extended prophylaxis with rivaroxaban and 5.5% of those receiving short-term enoxaparin.

Conclusion: Extended duration thromboprophylaxis with rivaroxaban was significantly more effective than short-term enoxaparin for the prevention of VTE in patients undergoing THR. Both regimens were associated with a similar incidence of bleeding. Extended thromboprophylaxis provides substantial benefits for patients undergoing THR and rivaroxaban provides a safe and effective option for this strategy.