1) Manesh R. Patel, et al, Rivaroxaban versus warfarin in nonvalvular atrial fibrillation, N Engl J Med. 2011 Sep 8;365(10):883-91. doi: 10.1056/NEJMoa1009638. Epub 2011 Aug 10.
2) Masatsugu Hori, et al, Rivaroxaban vs. warfarin in Japanese patients with atrial fibrillation – the J-ROCKET AF study -, Circ J. 2012;76(9):2104-11. Epub 2012 Jun 5.
3) Masatsugu Hori, et al, Safety and efficacy of adjusted dose of rivaroxaban in Japanese patients with non-valvular atrial fibrillation: subanalysis of J-ROCKET AF for patients with moderate renal impairment, Circ J. 2013;77(3):632-8. Epub 2012 Dec 8.
1) Rivaroxaban versus warfarin in nonvalvular atrial fibrillation
The use of warfarin reduces the rate of ischemic stroke in patients with atrial fibrillation but requires frequent monitoring and dose adjustment. Rivaroxaban, an oral factor Xa inhibitor, may provide more consistent and predictable anticoagulation than warfarin.
In a double-blind trial, we randomly assigned 14,264 patients with nonvalvular atrial fibrillation who were at increased risk for stroke to receive either rivaroxaban (at a daily dose of 20 mg) or dose-adjusted warfarin. The per-protocol, as-treated primary analysis was designed to determine whether rivaroxaban was noninferior to warfarin for the primary end point of stroke or systemic embolism.
In the primary analysis, the primary end point occurred in 188 patients in the rivaroxaban group (1.7% per year) and in 241 in the warfarin group (2.2% per year) (hazard ratio in the rivaroxaban group, 0.79; 95% confidence interval [CI], 0.66 to 0.96; P<0.001 for noninferiority). In the intention-to-treat analysis, the primary end point occurred in 269 patients in the rivaroxaban group (2.1% per year) and in 306 patients in the warfarin group (2.4% per year) (hazard ratio, 0.88; 95% CI, 0.74 to 1.03; P<0.001 for noninferiority; P=0.12 for superiority). Major and nonmajor clinically relevant bleeding occurred in 1475 patients in the rivaroxaban group (14.9% per year) and in 1449 in the warfarin group (14.5% per year) (hazard ratio, 1.03; 95% CI, 0.96 to 1.11; P=0.44), with significant reductions in intracranial hemorrhage (0.5% vs. 0.7%, P=0.02) and fatal bleeding (0.2% vs. 0.5%, P=0.003) in the rivaroxaban group. CONCLUSIONS: In patients with atrial fibrillation, rivaroxaban was noninferior to warfarin for the prevention of stroke or systemic embolism. There was no significant between-group difference in the risk of major bleeding, although intracranial and fatal bleeding occurred less frequently in the rivaroxaban group. (Funded by Johnson & Johnson and Bayer; ROCKET AF ClinicalTrials.gov number, NCT00403767.) 2) Rivaroxaban vs. warfarin in Japanese patients with atrial fibrillation – the J-ROCKET AF study – BACKGROUND: The global ROCKET AF study evaluated once-daily rivaroxaban vs. warfarin for stroke and systemic embolism prevention in patients with atrial fibrillation (AF). A separate trial, J-ROCKET AF, compared the safety of a Japan-specific rivaroxaban dose with warfarin administered according to Japanese guidelines in Japanese patients with AF. METHODS AND RESULTS: J-ROCKET AF was a prospective, randomized, double-blind, phase III trial. Patients (n=1,280) with non-valvular AF at increased risk for stroke were randomized to receive 15 mg once-daily rivaroxaban or warfarin dose-adjusted according to Japanese guidelines. The primary objective was to determine non-inferiority of rivaroxaban against warfarin for the principal safety outcome of major and non-major clinically relevant bleeding, in the on-treatment safety population. The primary efficacy endpoint was the composite of stroke and systemic embolism. Non-inferiority of rivaroxaban to warfarin was confirmed; the rate of the principal safety outcome was 18.04% per year in rivaroxaban-treated patients and 16.42% per year in warfarin-treated patients (hazard ratio [HR] 1.11; 95% confidence interval 0.87-1.42; P<0.001 [non-inferiority]). Intracranial hemorrhage rates were 0.8% with rivaroxaban and 1.6% with warfarin. There was a strong trend for a reduction in the rate of stroke/systemic embolism with rivaroxaban vs. warfarin (HR, 0.49; P=0.050). CONCLUSIONS: J-ROCKET AF demonstrated the safety of a Japan-specific rivaroxaban dose and supports bridging the global ROCKET AF results into Japanese clinical practice. 3) Safety and efficacy of adjusted dose of rivaroxaban in Japanese patients with non-valvular atrial fibrillation: subanalysis of J-ROCKET AF for patients with moderate renal impairment BACKGROUND: In the Japanese Rivaroxaban Once-daily oral direct factor Xa inhibition Compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation (J-ROCKET AF) study, rivaroxaban 15 mg once daily was given to patients with creatinine clearance (CrCl) ≥ 50 ml/min (preserved renal function), and was reduced to 10mg once daily in patients with CrCl 30-49 ml/min (moderate renal impairment). The aim of this subanalysis was to assess the safety and efficacy of the adjusted dose of rivaroxaban compared with warfarin in a cohort with moderate renal impairment. METHODS AND RESULTS: Compared with patients with preserved renal function, those with moderate renal impairment (22.2% of all randomized patients) had higher rates of bleeding and stroke events irrespective of study treatment. Among those with moderate renal impairment, the principal safety endpoint occurred at 27.76%/year with rivaroxaban vs. 22.85%/year with warfarin (hazard ratio [HR], 1.22; 95% confidence interval [CI]: 0.78-1.91) and the rate of the primary efficacy endpoint was 2.77%/year vs. 3.34%/year (HR, 0.82; 95% CI: 0.25-2.69), respectively. There were no significant interactions between renal function and study treatment in the principal safety and the primary efficacy endpoints (P=0.628, 0.279 for both interactions, respectively). CONCLUSIONS: The safety and efficacy of rivaroxaban vs. warfarin were consistent in patients with moderate renal impairment and preserved renal function. 【開催日】 2014年11月19日(水)