title: Rivaroxaban versus enoxaparin for thromboprophylaxis after total knee arthroplasty.
abstract: BACKGROUND
  We investigated the efficacy of rivaroxaban, an orally active direct factor Xa inhibitor, in preventing venous thrombosis after total knee arthroplasty.
  
  
  METHODS
  In this randomized, double-blind trial, 2531 patients who were to undergo total knee arthroplasty received either oral rivaroxaban, 10 mg once daily, beginning 6 to 8 hours after surgery, or subcutaneous enoxaparin, 40 mg once daily, beginning 12 hours before surgery. The primary efficacy outcome was the composite of any deep-vein thrombosis, nonfatal pulmonary embolism, or death from any cause within 13 to 17 days after surgery. Secondary efficacy outcomes included major venous thromboembolism (i.e., proximal deep-vein thrombosis, nonfatal pulmonary embolism, or death related to venous thromboembolism) and symptomatic venous thromboembolism. The primary safety outcome was major bleeding.
  
  
  RESULTS
  The primary efficacy outcome occurred in 79 of 824 patients (9.6%) who received rivaroxaban and in 166 of 878 (18.9%) who received enoxaparin (absolute risk reduction, 9.2%; 95% confidence interval [CI], 5.9 to 12.4; P<0.001). Major venous thromboembolism occurred in 9 of 908 patients (1.0%) given rivaroxaban and 24 of 925 (2.6%) given enoxaparin (absolute risk reduction, 1.6%; 95% CI, 0.4 to 2.8; P=0.01). Symptomatic events occurred less frequently with rivaroxaban than with enoxaparin (P=0.005). Major bleeding occurred in 0.6% of patients in the rivaroxaban group and 0.5% of patients in the enoxaparin group. The incidence of drug-related adverse events, mainly gastrointestinal, was 12.0% in the rivaroxaban group and 13.0% in the enoxaparin group.
  
  
  CONCLUSIONS
  Rivaroxaban was superior to enoxaparin for thromboprophylaxis after total knee arthroplasty, with similar rates of bleeding. (ClinicalTrials.gov number, NCT00361894.)
authors.affiliation: Nordsjaellands Hospital, Hørsholm, Denmark. mirula@noh.regionh.dk
authors.forename: Michael R
authors.initials: MR
authors.lastname: Lassen
authors.forename: Walter
authors.initials: W
authors.lastname: Ageno
authors.forename: Lars C
authors.initials: LC
authors.lastname: Borris
authors.forename: Jay R
authors.initials: JR
authors.lastname: Lieberman
authors.forename: Nadia
authors.initials: N
authors.lastname: Rosencher
authors.forename: Tiemo J
authors.initials: TJ
authors.lastname: Bandel
authors.forename: Frank
authors.initials: F
authors.lastname: Misselwitz
authors.forename: Alexander G G
authors.initials: AG
authors.lastname: Turpie
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000009:adverse effects / Q000627:therapeutic use*; D019645:Arthroplasty, Replacement, Knee; D004311:Double-Blind Method; D017984:Enoxaparin / Q000009:adverse effects / Q000627:therapeutic use*; D065427:Factor Xa Inhibitors; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009025:Morpholines / Q000009:adverse effects / Q000627:therapeutic use*; D011655:Pulmonary Embolism / Q000453:epidemiology / Q000517:prevention & control; D000069552:Rivaroxaban; D013876:Thiophenes / Q000009:adverse effects / Q000627:therapeutic use*; D054556:Venous Thromboembolism / Q000453:epidemiology / Q000401:mortality / Q000517:prevention & control*; D020246:Venous Thrombosis / Q000453:epidemiology / Q000517:prevention & control
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin; D065427:Factor Xa Inhibitors; D009025:Morpholines; D013876:Thiophenes; D000069552:Rivaroxaban