Ralinepag

Ralinepag is a potent, orally bioavailable and non-prostanoid prostacyclin (IP) receptor agonist, with EC₅₀s of 8.5 nM, 530 nM and 850 nM for human and rat IP receptor and human DP1 receptor, respectively. IC50 & Target:EC50: 8.5 nM (Human IP receptor), 530 nM (Rat IP receptor), 850 nM (Human DP1 receptor)^[1] In Vitro: Ralinepag is a potent non-prostanoid prostacyclin receptor agonist, with EC₅₀s of 8.5 nM, 530 nM and 850 nM for human and rat IP receptor and human DP1 receptor, respectively. Ralinepag (5c) has potent receptor binding affinity at prostaglandin receptor, with K_is of 1.2 nM, 3 nM, 76 nM, and 256 nM for monkey, human, rat, and dog IP receptor (ligand, [³H]-iloprost), and 2.6 μM, 9.6 μM, 610 nM, 143 nM, and 678 nM for human DP1, EP1, EP2, EP3v6 and EP4 receptors (ligand, [³H]-PGE2), respectively. Moreover, Ralinepag shows no effect on cytochrome P450 enzymes (IC₅₀ > 50 μM for CYPs 1A2, 2D6, 3A4 2C8, 2C9, and 2C19) or hERG channel functional activity in a patch clamp assay (IC₅₀ > 30 μM). Ralinepag also inhibits the ADP-induced human platelet aggregation, with an IC₅₀ of 38 nM^[1]. In Vivo: Ralinepag (30 mg/kg, p.o.) markedly reduces the monocrotaline (MCT)-induced increase in pulmonary arterial pressure and pulmonary vessel wall thickness in rats^[1].