A dual antagonist for chemokine CCR3 receptor and histamine H1 receptor.

Eosinophilic chemokines and histamine play distinct but important roles in allergic diseases. Inhibition of both eosinophilic chemokines and histamine, therefore, is an ideal strategy for the treatment of allergic inflammation, such as asthma, allergic rhinitis, and atopic dermatitis. YM-344484 was found to potently inhibit both the CCL11-induced Ca2+ influx in human CCR3-expressing cells (Kb=1.8 nM) and histamine-induced Ca2+ influx in histamine H1 receptor-expressing PC3 cells (Kb=47 nM). YM-344484 also inhibited the CCL11-induced chemotaxis of human CCR3-expressing cells (IC50=6.2 nM) and CCL11-induced eosinophil-derived neurotoxin release from human eosinophils (IC50=19 nM). Orally administered YM-344484 inhibited the increase in histamine-induced vascular permeability in mice (82% inhibition at a dose of 10 mg/kg) and the accumulation of eosinophils in a mouse asthma model (74% at a dose of 300 mg/kg). These results indicate that YM-344484, a novel and functional dual antagonist for chemokine CCR3 receptor and histamine H1 receptor, is an attractive candidate for development as a novel anti-allergic inflammation drug.