Thromb Haemost 2012; 108(05): 896-902
DOI: 10.1160/TH12-04-0267
Blood Coagulation, Fibrinolysis and Cellular Haemostasis
Schattauer GmbH

Plasma factor Xa inhibition can predict antithrombotic effects of oral direct factor Xa inhibitors in rabbit atherothrombosis models

Toshiyuki Funatsu
1   Applied Pharmacology Research Laboratories, Ibaraki, Japan
,
Atsushi Yamashita
2   Department of Pathology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
,
Seiji Kaku
1   Applied Pharmacology Research Laboratories, Ibaraki, Japan
,
Yoshiyuki Iwatsuki
1   Applied Pharmacology Research Laboratories, Ibaraki, Japan
,
Yujiro Asada
2   Department of Pathology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
› Author Affiliations
Further Information

Publication History

Received: 28 April 2012

Accepted after major revision: 16 August 2012

Publication Date:
29 November 2017 (online)

Preview

Summary

We evaluated the relationship between antithrombotic effects and pharmacodynamic (PD) marker changes produced by the novel factor (F)Xa inhibitors darexaban (YM150) and rivaroxaban in a rabbit model of plaque disruption-induced arterial thrombosis. Animals were subjected to catheter-induced endothelial denudation via the femoral artery followed by a two-week high-cholesterol diet. Plaque disruption was induced by balloon angioplasty, and then stasis was achieved by ligation at the distal side of the injured segment. Darexaban and rivaroxaban were administered orally 1 hour (h) before and 9 h after plaque disruption, and their antithrombotic effects were evaluated 24 h after the initiation of ligation. Prothrombin time (PT), activated partial thromboplastin time (APTT), and plasma FXa activity were measured using blood samples collected before and 1 h after administration. Darexaban and rivaroxaban significantly reduced thrombus formation. The thrombus weight obtained in the 30 mg/kg darexaban group was comparable to that in the 1 mg/kg rivaroxaban group (2.17 ± 0.63 and 3.23 ± 1.64 mg, respectively, vs. 8.01 ± 1.08 mg in the control group). Plasma FXa activity correlated with the antithrombotic effects of darexaban and rivaroxaban, while PT only correlated with those of darexaban. Our findings suggest that the degree of plasma FXa inhibition may be useful for predicting antithrombotic effects of darexaban and rivaroxaban in arterial thrombosis. PT may also be useful in evaluating antithrombotic effects of darexaban in particular.