851723-84-7

OC000459 is a potent and selective D prostanoid receptor 2 (DP2) antagonist with IC50 of 13 nM.IC50 Value: 13 nM( Ki for hrCRTH2); 3 nM( Ki for Rat rCRTH2);13 nM(Ki for human native CRTH2)Target: D prostanoid receptor 2CRTH2 (chemoattractant receptor expressed on T-helper (Th) type 2 cells) is a G-protein-coupled receptor expressed by Th2 lymphocytes and eosinophils that mediates prostaglandin (PG)D(2)-driven chemotaxis[1]. CRTH2 mediates activation of Th2 cells, eosinophils and basophils in response to prostaglandin D(2). The CRTH2 antagonist OC000459 has been demonstrated to reduce airway inflammation and improve lung function in moderate persistent asthma[2].in vitro: OC000459 is an indole-acetic acid derivative that potently displaces [3H]PGD2from human recombinant DP2 (Ki = 0.013 μM), rat recombinant DP2 (Ki = 0.003 μM), and human native DP2 (Th2 cell membranes; Ki = 0.004 μM) but does not interfere with the ligand binding properties or functional activities of other prostanoid receptors (prostaglandin E1-4 receptors, D prostanoid receptor 1, thromboxane receptor, prostacyclin receptor, and prostaglandin F receptor). OC000459 inhibited chemotaxis (IC50 = 0.028 μM) of human Th2 lymphocytes and cytokine production (IC50 = 0.019 μM) by human Th2 lymphocytes. OC000459 competitively antagonized eosinophil shape change responses induced by PGD2 in both isolated human leukocytes (pKB = 7.9) and human whole blood (pKB = 7.5) but did not inhibit responses to eotaxin, 5-oxo-eicosatetraenoic acid, or complement component C5a. OC000459 also inhibited the activation of Th2 cells and eosinophils in response to supernatants from IgE/anti-IgE-activated human mast cells. OC000459 had no significant inhibitory activity on a battery of 69 receptors and 19 enzymes including cyclooxygenase 1 (COX1) and COX2[3] .in vivo: OC000459 was found to be orally bioavailable in rats and effective in inhibiting blood eosinophilia induced by 13,14-dihydro-15-keto-PGD2 (DK-PGD2) in this species (ED50 = 0.04 mg/kg p.o.) and airway eosinophilia in response to an aerosol of DK-PGD2 in guinea pigs (ED50 = 0.01 mg/kg p.o.) [3].Clinical trial: N/A.