AM103 is an effective and selective inhibitor of FLAP (IC50 = 4.2 nM).

AM103 is against the 5 most common CYP isoforms with IC50s >30 μM for CYP2D6 and >50 μM for CYP3A4, CYP2C9, CYP2C19, and CYP1A2[1]. AM103 shows IC50s of 350, 113, and 117 nM against human, rat, and mouse whole-blood ionophore-stimulated LTB4 production, respectively[2].

AM103 has high bioavailability of 64%, low clearance of 2.9 mL/min/kg, low volume of distribution of 0.41 L/kg, and a long i.v. half-life of 5.2 h in dogs. AM103 (10 mg/kg) inhibits the increase in CysLTs and EPO by approximately 60% and reduces the level of IL-5[1]. In a model of chronic lung inflammation using ovalbumin-primed and challenged BALB/c mice, AM103 reduces eosinophil peroxidase, CysLTs, and IL-5 in the bronchoalveolar lavage fluid. AM103 increases survival time in mice exposed to a lethal intravenous injection of platelet-activating factor. In the rat lung challenged in vivo with calcium ionophore, AM103 inhibits LTB4 and cysteinyl leukotriene production with ED50 values of 0.8 and 1 mg/kg, respectively[2].