Adriforant hydrochloride is an antagonist of histamine H4 receptor.

H4 receptor func:1.56 nM (ki), H4 receptor bind:ki:2.4 nM

Adriforant in vitro IC50 on human native isolated eosinophils assessing actin polymerisation is 1.16 nM and assuming need 10 times the IC50 for >90% receptor occupancy (and therefore near complete inhibition of the response) suggested a concentration of 12 nM. The data in the whole blood GAFS assay demonstrates that the imetit induced shape change is completely blocked at a total blood concentration of 30 nM (which correcting for PPB and blood partitioning equates to approximately 10 nM free). For the purpose of dose projection and safety margin calculation, a Ceff/Cmin concentration of 10-15 nM is used