Description
Rivaroxaban is an oral, direct inhibitor of Factor X, being developed for the prevention and treatment of arterial and venous thrombosis with a Ki of 0.4 nM. Rivaroxaban also inhibits prothrombinase activity (IC50 = 2.1 nM). Rivaroxaban also shows a similar affinity to purified human (IC50 = 0.7 nM) and rabbit Factor X (IC50 = 0.8 nM), but a lesser potency against purified rat Factor X (IC50 = 3.4 nM). Endogenous human and rabbit Factor X in plasma is inhibited to a similar extent by Rivaroxaban (IC50 = 21 nM and 21 nM, respectively), while 14-fold higher concentrations are required in rat plasma (IC50 = 290 nM). Rivaroxaban exhibits high permeability and polarized transport across Caco-2 cells as a substrate of the P-gp, but exhibits no inhibitory effect on P-gp-mediated drug transport up to concentrations of 100 µM in vitro