PF-04418948 NLT 98%

PF-04418948 is a novel, potent and selective prostaglandin EP2 receptor antagonist with IC50 of 16 nM, displays >2000-fold functional selectivity for the human EP2 receptor over antagonist activity against the human EP1, EP3, EP4, DP1 and CRTH2 receptors. IC50 value: 16 nM Target: EP2 in vitro: PF-04418948 inhibits prostaglandin E2 (PGE2)-induced increase in cAMP in cells expressing EP2 receptors with a functional KB value of 1.8 nM. In human myometrium, PF-04418948 produced a parallel, rightward shift of the butaprost-induced inhibition of the contractions induced by electrical field stimulation with an apparent KB of 5.4 nM. [1] in vivo: In dog bronchiole and mouse trachea, PF-04418948 produced parallel rightward shifts of the PGE2-induced relaxation curve with a KB of 2.5 nM and an apparent KB of 1.3 nM respectively. Reversal of the PGE2-induced relaxation in the mouse trachea by PF-04418948 produced an IC50 value of 2.7 nM. Given orally, PF-04418948 attenuated the butaprost-induced cutaneous blood flow response in rats. [1] PF-04418948 competitively inhibits relaxations of murine and guinea pig trachea induced by ONO-AE1-259 and PGE2 respectively.[2]