Therapeutic efficacy of AM156, a novel prostanoid DP2 receptor antagonist, in murine models of allergic rhinitis and house dust mite-induced pulmonary inflammation

Prostaglandin D2 (PGD2) is derived from arachidonic acid and binds with high affinity to the G protein coupled receptors prostanoid DP1 and DP2. Interaction with DP2 results in cell chemotaxis, eosinophil degranulation, eosinophil shape change, adhesion molecule upregulation and Th2 cytokine production. In allergic rhinitis and allergic asthma PGD2 is released from mast cells in response to allergen challenge and may trigger symptoms such as sneezing, rhinorrhea, pruritus, mucus hypersecretion and pulmonary inflammation. In Japan, ramatroban, a dual prostanoid DP2/prostanoid TP receptor antagonist, is marketed for allergic rhinitis while selective DP2 antagonists are currently under investigation as therapeutics for asthma and allergic rhinitis. In the studies described herein, we investigated the efficacy of AM156, a novel selective prostanoid DP2 receptor antagonist, in murine models of allergic rhinitis and asthma. AM156 inhibited sneezing and nasal rubs in a model of allergic rhinitis. AM156 inhibited pulmonary inflammation and mucus hypersecretion induced by chronic inhalation of house dust mite. These results suggest that selective prostanoid DP2 receptor antagonists such as AM156 may provide beneficial effects for the clinical treatment of diseases such as allergic rhinitis and asthma.