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11:17
Rapid Point-of-Care Assay of Enoxaparin Anticoagulant Efficacy in Whole Blood
Published on: October 12, 2012
Apixaban or enoxaparin for thromboprophylaxis after knee replacement
Michael Rud Lassen1, Gary E Raskob, Alexander Gallus
1Department of Orthopedics, Spine Clinic, Clinical Trial Unit, Hørsholm Hospital, University of Copenhagen, Hørsholm, Denmark.
The New England Journal of Medicine
|August 7, 2009
Summary
Apixaban did not prove noninferior to enoxaparin for preventing clots after knee replacement. However, apixaban showed significantly lower bleeding rates, suggesting a potentially safer option for thromboprophylaxis.
Area of Science:
- Orthopedic Surgery
- Pharmacology
- Vascular Medicine
Background:
- Optimal thromboprophylaxis after major joint replacement remains undefined.
- Low-molecular-weight heparins (LMWHs) like enoxaparin target Factor Xa and thrombin.
- Apixaban, a selective Factor Xa inhibitor, offers potential for effective prophylaxis with reduced bleeding risk.
Purpose of the Study:
- To compare the efficacy and safety of apixaban versus enoxaparin for thromboprophylaxis in patients undergoing total knee replacement.
- To evaluate apixaban's noninferiority against enoxaparin in preventing venous thromboembolism.
Main Methods:
- A double-blind, double-dummy, randomized study involving 3195 patients undergoing total knee replacement.
- Patients received either oral apixaban (2.5 mg twice daily) or subcutaneous enoxaparin (30 mg every 12 hours) for 10-14 days post-surgery.
- Primary efficacy outcome: composite of deep-vein thrombosis (DVT), pulmonary embolism (PE), and all-cause death; followed for 60 days.
Main Results:
- The primary efficacy event rate was 9.0% for apixaban versus 8.8% for enoxaparin (Relative Risk: 1.02; 95% CI: 0.78-1.32), failing to meet noninferiority criteria.
- Clinically relevant bleeding occurred in 2.9% of the apixaban group compared to 4.3% in the enoxaparin group (P=0.03).
- Adverse event profiles were similar between the two treatment groups.
Conclusions:
- Apixaban did not achieve noninferiority compared to enoxaparin for thromboprophylaxis after knee replacement.
- Apixaban demonstrated a statistically significant reduction in clinically relevant bleeding events.
- The study suggests apixaban may offer a safer alternative with comparable efficacy and adverse event profiles.
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