Biochem/physiol Actions
Abarelix (PPI-149) is a gonadotropin releasing hormone (GnRH)/luteinizing hormone releasing hormone (LHRH) receptor (GnRHR, LHRHR) antagonist with low histamine release induction propensity (EC50 = 100 μg/mL; rat mast cells). Abarelix exhibits good in vivo efficacy via iv. or sc. in suppressing LH levels in castrated male rats (plasma LH = 12/1.2/0.9/1.2 ng/mL 6 hrs post 0/12.5/50/200 μg/kg in 5% mannitol sc.) and in lowering testosterone among intact male rats (plasma testosterone = 1.64/0.29 ng/mL 6 hrs post 0/3 μg/kg sc.).
Gonadotropin releasing hormone (GnRH)/ luteinizing hormone releasing hormone (LHRH) receptor (GnRHR, LHRHR) antagonist.