The (-)-enantiomer with the S-absolute configuration was responsible for the high aromatase inhibitory activity of (R)-Fadrozole[1].

(R)-fadrozole (0.24 and 1.2 mg/kg; daily; oral) and (S)-fadrozole similarly decreases plasma aldosterone levels, whereas urinary aldosterone excretion rate was reduced only by S-fadrozole[2]. (R)-fadrozole (0.24 and 1.2 mg/kg; daily; oral) effectively reverses preexistent left ventricular interstitial fibrosis by 50% (vs. 42% for canrenoate), S-fadrozole was devoid of an antifibrotic effect[2]. Animal Model: SHHF rats[2]Dosage: 0.24 and 1.2 mg/kg Administration: Daily; oral Result: Decreased plasma aldosterone levels and reversed preexistent left ventricular interstitial fibrosis.