Ximelagatran--recent comparisons with warfarin.
Recently, ximelagatran and warfarin have been compared for stroke prevention in the Stroke Prevention using an Oral Thrombin Inhibitor in Atrial Fibrillation (SPORTIF) V trial in patients with non-valvular atrial fibrillation, and for the treatment of deep vein thrombosis in the Thrombin Inhibitor in Venous Thromboembolism (THRIVE) trial. In a mean follow-up of 20 months in SPORTIF V, the primary end point of stroke or systemic embolic events occurred in 37 patients in the warfarin group (of 1962) and 51 in the ximelagatran group (1960 patients). There was no difference between the groups in major bleeding. The rates of elevated alanine aminotransferase were much higher in the ximelagatran group (6%) than in the warfarin group (0.8%). In THRIVE, the primary efficacy end point of recurrent venous thromboembolism occurred in 26/1240 ximelagatran patients and 24/1249 patients in the enoxaparin/warfarin group. The incidence of alanine aminotransferase levels greater than three times the upper limit of normal was much higher with ximelagatran than with enoxaparin/warfarin (9.6 and 2.0%, respectively). In conclusion, although the trials comparing ximelagatran with warfarin as prophylaxis for stroke in atrial fibrillation and in the treatment of venous thromboembolism show noninferiority, concerns about the hepatic safety of ximelagatran remain.
Doggrell
Sheila A
SA
Health Practice Division, Auckland University of Technology, Akoranga Campus, Northcote, Auckland, New Zealand. s.doggrell@xtra.co.nz