P4pal10 is an antagonist for protease-activated receptor 4 ( PAR4 ). P4pal10 inhibits the platelet aggregation, inhibits tissue factor (TF)-induced thrombin generation, and exhibits anticoagulant and antithrombotic activities. P4pal10 reduces the oedema and the granulocyte infiltration induced by Carrageenan. P4pal10 ameliorates the injury in mice myocardial ischemia/reperfusion (I/R) models.