1396006-71-5

Oral dosing of LPA1 receptor antagonist 1 in mice causes a dose-dependent reduction in serum histamine levels induced following intravenous LPA stimulation. When mice are orally dosed with LPA1 antagonist 1 (100 mg/kg, aqueous suspension) prior to intravenous LPA injection, the LPA-induced histamine level is significantly blocked A clear PK/PD relationship is demonstrated by the correlation between the levels of LPA1 receptor antagonist 1 and LPA-induced histamine concentrations in plasma. Although AM095 almost completely blocks histamine release (100 mg/kg), analysis of plasma samples revealed more than 65-fold higher concentrations of AM095 than LPA1 receptor antagonist 1 (100 mg/kg). The ability of LPA1 receptor antagonist 1 to block histamine release at much lower plasma concentration suggests that further improvement of pharmacokinetic properties of this chemical class could lower the effective dose^[1].