AHA: Edoxaban Noninferior to Warfarin for Stroke Prevention
Two additional studies discuss use of pharmacogenetic-guided dosing of warfarin
TUESDAY, Nov. 19, 2013 (HealthDay News) -- Once-daily edoxaban is noninferior to warfarin for prevention of stroke or systemic embolism; and genotype-guided dosing of warfarin may be beneficial, according to three studies published online Nov. 19 in the New England Journal of Medicine. The research was published to coincide with the American Heart Association's 2013 Scientific Sessions, held from Nov. 16 to 19 in Dallas.
Robert P. Giugliano, M.D., from Brigham and Women's Hospital and Harvard Medical School in Boston, and colleagues compared once-daily regimens of edoxaban with warfarin in 21,105 patients with atrial fibrillation. The researchers found that the primary end point of stroke or systemic embolism was 1.50 percent with warfarin versus 1.18 percent with high-dose edoxaban (hazard ratio, 0.79; P < 0.001 for noninferiority) and 1.61 percent for low-dose edoxaban (hazard ratio, 1.07; P = 0.005 for noninferiority).
Stephen E. Kimmel, M.D., from the Center for Therapeutic Effectiveness Research in Philadelphia, and colleagues randomized 1,015 patients to receive genotype-guided dosing of warfarin or clinical variable-based dosing. The researchers observed no significant difference in the mean percentage of time in the therapeutic range between the groups at four weeks (adjusted mean difference, −0.2; P = 0.91). Munir Pirmohamed, Ph.D., from the University of Liverpool in the United Kingdom, and colleagues found that genotype-guided therapy correlated with a higher percentage of time in the therapeutic international normalized ratio range for patients with atrial fibrillation or venous thromboembolism initiating warfarin (67.4 versus 60.3 percent; P < 0.001).
"Whether this will translate into improved clinical outcomes is unclear," Pirmohamed and colleagues write.
Several authors from the Giugliano study disclosed financial ties to pharmaceutical companies, including Daiichi Sankyo Pharma Development, which funded the study.