NE 52-QQ57 is a selective, and orally available GPR4 antagonist with an IC50 of 70 nM. NE 52-QQ57 has anti-inflammatory activity.IC50 & Target: IC50: 70 nM (GPR4).In Vitro: NE 52-QQ57 effectively blocks GPR4-mediated cAMP accumulation (IC50 26.8?nM in HEK293?cells)[2].In Vivo: NE 52-QQ57 (Compound 13) shows a significant anti-inflammatory effect in the rat antigen induced arthritis model after oral administration at 30 mg/kg bid for 20 days.NE 52-QQ57 (30 mg/kg bid po for 4 days) also prevents angiogenesis in the mouse chamber model as well as pain as demonstrated in the rat complete Freund’s adjuvant model.