Sparsentan (RE-021) effectively blocks angiotensin II-induced blood pressure increases, with an effective dose (ED50) of 0.8 µmol/kg when administered intravenously and 3.6 µmol/kg orally. Additionally, Sparsentan has shown effectiveness and a prolonged action in the big ET-1-induced pressor model, significantly reducing blood pressure at the lowest dose tested (10 µmol/kg/day) in spontaneously hypertensive rats. It exhibits favorable oral bioavailability across various species—rats, dogs, and monkeys—with bioavailability percentages averaging 40%, 86%, and 21%, respectively. At a dosage of 100 µmol/kg/day, Sparsentan can reduce blood pressure significantly, effectively normalizing blood pressure levels in spontaneously hypertensive rats over its pharmacokinetic duration^[1].