Setipiprant (ACT-129968, KYTH-105) is a potent, selective and orally available CRTH2 antagonist with IC50 of 6 nM.
Setipiprant is selective for CRTH2/DP2 over DP1 in a radioligand binding assay (IC50=1,290 nM) and the prostaglandin E2 receptor subtypes EP2 and EP4 in a β-arrestin assay (IC50s=2,600 and >10,000 nM, respectively).
Setipiprant inhibited PGD2-induced calcium flux in HEK293 cells expressing human CRTH2/DP2 (IC50 = 30 nM) and PGD2-induced shape change in human eosinophils (IC50=235 nM).
Setipiprant reduced both the allergen-induced LAR and the associated AHR in allergic asthmatics.
