PTR-36

PTR-36 is an orally bioavailable small molecule antagonist of the CRTH2 (Chemoattractant receptor-homologous molecule expressed on Th2 cells) receptor, also known as the DP2 (Prostaglandin D2 receptor 2). Developed by Teijin Pharma Limited through a licensing agreement with Pulmagen Therapeutics, PTR-36 is currently in clinical development for the treatment of bronchial asthma. The CRTH2 receptor is a G protein-coupled receptor expressed on key inflammatory cells, including Th2 lymphocytes, eosinophils, and basophils. Activation of CRTH2 by prostaglandin D2 (PGD2) promotes the recruitment and activation of these cells, driving the type 2 inflammation characteristic of allergic asthma. By blocking this pathway, PTR-36 aims to reduce airway inflammation and provide a systemic, non-steroidal treatment option for patients whose asthma is not adequately controlled by inhaled corticosteroids or combination therapies.