MK-2894 is a highly potent and selective inhibitor of EP4 receptor with IC50 value of 2.5 nM [1].

MK-2894 is a highly selective and potent second generation EP4 antagonist with a Ki of 0.56±0.1nM in the radio ligand binding assay using membranes prepared from human EP1-4 overexpressed HEK 293 cell lines. And the EP4 functional assay measures the inhibition of PGE2-induced cAMP accumulation with IC50 of 2.5±0.7nM. In the AIA model and GI tolerability model in male SD rats, MK-2894 shows a dose-dependent inhibition of pain response with ED50 of 0.36 mg/kg. It also has the potent activity in inhibiting chronic pawswelling with ED50 of 0.02 mg/kg/day. Overall, MK-2894 displays the desired potency, selectivity, pharmacokinetic, and GI tolerability profile for further development and represents a potential safer alternative for treating pain and inflammation than traditional NSAIDs and coxibs [1].

References:
[1] Marc Blouin, Yongxin Han, Jason Burch, Julie Farand, Christophe Mellon, Mireille Gaudreault, Mark Wrona, Jean-Francois Levesque, Danielle Denis, Marie-Claude Mathieu, Rino Stocco, Erika Vigneault, Alex Therien, Patsy Clark, Steve Rowland, Daigen Xu, Gary O’Neill, Yves Ducharme and Rick Friesen. The Discovery of 4-{1-[({2,5-Dimethyl-4-[4-(trifluoromethyl)benzyl]-3-thienyl}carbonyl)amino]cyclopropyl}benzoic Acid (MK-2894), A Potent and Selective Prostaglandin E2 Subtype 4 Receptor Antagonist. J. Med. Chem. 2010, 53: 2227–2238.