Betrixaban (PRT-054021) is a highly potent, selective, and orally efficacious factor Xa inhibitor with IC50 of 1.2 nM(inhibition of Factor 10a).
IC50 value: 1.2 nM [1]
Target: Factor Xa
Betrixaban (PRT-054021) is an anticoagulant drug which acts as a direct factor Xa inhibitor. It is potent, orally active and highly selective for factor Xa, being selected from a group of similar compounds for its low hERG affinity. Betrixaban has undergone human clinical trials for prevention of embolism after knee surgery, and prevention of stroke following atrial fibrillation, with promising results.
Betrixaban, the fifth novel oral anticoagulant in line for the Food and Drug Administration (FDA) approval, possesses some unique pharmacokinetic characteristics in comparison with the currently available novel anticoagulants, including limited renal excretion, minimal metabolism through the cytochrome p450 system and a long half-life. This pharmacokinetic profile may allow greater flexibility for use in patients with poor renal function, offer the convenience of once daily dosing, and exhibit less drug interactions. Betrixaban is currently being evaluated for prophylaxis against venous thromboembolic disease (VTED) and the prevention of stroke and systemic embolism associated with nonvalvular atrial fibrillation, its role in the management of acute VTED and acute coronary syndromes is yet to be defined based on clinical data and evaluation. Of interest, a factor Xa decoy, PRT4445, is currently under evaluation in conjunction with betrixaban, and may be a universal reversal agent for all anticoagulants with anti-Xa activity. Currently, there are no specific reversal agents for the novel anticoagulants. The availability of an effective reversal agent would be very attractive for the management of associated bleeding, bleeding due to trauma, or the need for emergent surgery.

5-R-Rivaroxaban

5-R-Rivaroxaban is (R) enantiomer of Rivaroxaban. Rivaroxaban (Xarelto; BAY 59-7939) is a novel, oral, direct Factor Xa (FXa) inhibitor in late-stage development for the prevention and treatment of thromboembolic disorders.
IC50 value:
Target: Factor Xa
Rivaroxaban (Xarelto; BAY 59-7939) inhibits clot-associated,free FXa activity,and prothrombinase activity, in addition, it reduces thrombin generation. Rivaroxaban (Xarelto; BAY 59-7939) is useful for antithrombotic agent.