BAY-298 is an orally active and selective luteinizing hormone receptor (LH-R) antagonist with IC 50 s of 96 nM, 23 nM and 78 nM for hLH (human LH) and rLH (rat LH) and cLH (cynomolgus monkey LH), respectively. BAY-298 is the first nanomolar hLH-R antagonist reducing sex hormone levels in vivo[1].

LH (cynomolgus monkey):78 nM , LH (rat):46nM , LH (human):185 nM

BAY-298 (oral; 4.5-72 mg/kg/day; for 8 days) dose-dependently reduces serum estradiol levels in proestrus [1]. BAY-298 (iv of 0.5 mg/kg or po of 2 mg/kg) has t 1/2 s of 31 hours and 33 hours for iv and po. And the C max s are 0.28 kg/L and 0.066 kg/L for iv and po [1]. Animal Model: Intact female rats [1] Dosage: 4.5, 9, 18, 36, 72 mg/kg Administration: Oral; for 8 days Result: Dosedependently lowered serum estradiol levels in proestrus. Animal Model: Female and male Wistar rats [1] Dosage: 0.5 mg/kg of iv or 2 mg/kg of po Administration: Iv or po Result: Has t 1/2 s of 31 hours and 33 hours for iv and po. And the C max s are 0.28 kg/L and 0.066 kg/L for iv and po.