LY3127760

LY3127760 is a potent and selective antagonist of the prostaglandin E4 (EP4) receptor, developed as an oral small molecule. It exhibits high affinity for the human EP4 receptor (binding Ki of 58 nM; cAMP IC50 of 5.6 nM) and shows exquisite selectivity over other EP receptors, with no detectable binding to EP1, EP2, or EP3[1]. The drug demonstrated analgesic and anti-inflammatory efficacy in preclinical models such as rat monoiodoacetate-induced pain, adjuvant arthritis, and migraine models[2]. In clinical studies involving healthy volunteers, LY3127760 was well tolerated with a safety profile similar to celecoxib. Pharmacodynamically, it increased ex vivo TNF-alpha release after LPS/prostaglandin E2 stimulation in a dose-dependent manner—consistent with blockade of the EP4 receptor—and had effects on prostacyclin synthesis and renal sodium retention comparable to celecoxib[2][3][6]. Developed by Eli Lilly for potential use in inflammatory conditions such as rheumatoid arthritis and pain management, its development reached phase 1/phase 2 trials but has not been approved for any indication[5].