AZD3778

AZD3778 is an investigational small molecule dual antagonist targeting the CC-chemokine receptor-3 (CCR3) and the histamine H1 receptor. Developed by AstraZeneca, it was designed to treat seasonal allergic rhinitis by combining anti-eosinophilic and antihistamine mechanisms. CCR3 is a G protein-coupled receptor expressed on key cells involved in allergic inflammation, including eosinophils, basophils, mast cells, and Th2-lymphocytes. By blocking CCR3, the drug aims to reduce eosinophil recruitment and activation, while its H1 receptor antagonism addresses immediate allergic symptoms. In Phase II clinical trials, AZD3778 demonstrated statistically significant reductions in nasal symptom scores and eosinophil cationic protein (ECP) levels compared to placebo and loratadine, suggesting that its dual mechanism provides therapeutic benefits beyond standard antihistamines.