Ifetroban is a long-acting thromboxane A2 receptor antagonist, with antiplatelet activity. IC50 & Target: Thromboxane A2 receptor^[1] In Vitro: Ifetroban is a long-acting thromboxane/prostaglandin endoperoxide receptor antagonist, with antiplatelet activity^[1]. In Vivo: Ifetroban (20, 40 mg/kg/day, i.p.) shows no effect on the blood pressure in stroke-prone spontaneously hypertensive rats^[1]. Ifetroban (BMS 180,291; 1 and 3 mg/kg, p.o.) inhibits aggregation and antagonizes TP-receptor in monekys. Ifetroban (3 mg/kg, i.v.) causes only marginal and transient hemodynamic effects in anesthetized African green monkeys^[2].