Sparsentan dose dependently antagonizes the angiotensin II-induced pressor response with an ED ₅₀ value of 0.8 μmol/kg iv and 3.6 μmol/kg po. Sparsentan also shows efficacious and long acting in the big ET-1-induced pressor model. Sparsentan causes a significant lowering of blood pressure at the lowest dose tested (10 μmol/kg/day) in spontaneously hypertensive rats. Sparsentan shows good oral bioavailability in rats, dogs, and monkeys, averaging 40%, 86%, and 21% F, respectively. At 100 μmol/kg/day, Sparsentan reduces the blood pressure from 170 to less than 100 mmHg during the course of the drug’s pharmacokinetic duration. Sparsentan at 100 μmol/kg/day essentially converts the spontaneously hypertensive rats into normotensive rats during the course of its pharmacokinetic duration.