BI-671800 (S0495-GRP)

BI-671800 (AP-761, Cmpd A) is a highly specific and potent antagonist of chemoattractant receptor-homologous molecule on Th2 cells (DP2/CRTH2) with IC50 of 4.5 nM and 3.7 nM for PGD2 binding to human CRTH2 and murine CRTH2, respectively. BI-671800 is associated with a small improvement in FEV1 in symptomatic controller-naïve asthma patients, and in patients on ICS.