CRTH2-IN-1 is a selective prostaglandin D2 receptor DP2 (CRTH2) antagonist, a Ramatroban analog, with an IC50 of 6 nM in the human DP2 binding assay.

CYP3A4:7 μM, DP1 (human):1 μM, DP2 (human):6 nM, CYP2C9:5 μM

CRTH2-IN-1 (Ramatroban analog) is a new type of prostaglandin D2 receptor DP2 (CRTH2) antagonist with IC50 of 7 nM in human whole blood eosinophil deformation assay (hESC). It has efficacy in a mouse model of allergic rhinitis. Using 3H-PGD2 and human platelet membrane for human prostaglandin D1 receptor (hDP1) binding. Human thromboxane receptor (hTP) binding was performed using human platelet membrane and 3H-SQ-29,548. HIP / 293 membrane and 3Hiloprost were used for human prostacyclin receptor (hIP) binding. CRTH2-IN-1 inhibits hDP1 binding with IC50 of 1 μM. CRTH2-IN-1 inhibits the combination of hTP and hIP with IC50 greater than 100 μM. CRTH2-IN-1 inhibits human CYP subtypes CYP3A4, CYP 2C9 and CYP2D6 with IC50 of 7, 5 and> 30 μM, respectively.