BIIF 1149 BS

BIIF 1149 BS is a small molecule antagonist of the leukotriene B4 receptor 1 (BLT1), developed by Boehringer Ingelheim for the treatment of inflammatory respiratory diseases, including asthma and allergic rhinitis. It is the active moiety (or a specific salt form) of the prodrug BIIL 284 (amelubant). By selectively binding to the BLT1 receptor, BIIF 1149 BS inhibits the biological actions of leukotriene B4 (LTB4), a potent chemoattractant and activator of neutrophils, eosinophils, and macrophages. This inhibition is intended to reduce the airway inflammation and hyperresponsiveness characteristic of asthma and allergic rhinitis. Although the compound was evaluated in Phase 1 clinical trials for safety, tolerability, and pharmacokinetics, further development of the LTB4 antagonist program by Boehringer Ingelheim was discontinued after later-stage candidates failed to demonstrate sufficient clinical efficacy.