Pharmacological Profile of AZD8871 (LAS191351), a Novel Inhaled Dual M3 Receptor Antagonist/β2-Adrenoceptor Agonist Molecule with Long-Lasting Effects and Favorable Safety Profile

AZD8871 is a novel muscarinic antagonist and β2-adrenoceptor agonist in development for chronic obstructive pulmonary disease. This study describes the pharmacological profile of AZD8871 in in vitro and in vivo assays. AZD8871 is potent at the human M3 receptor (pIC50 in binding assays: 9.5) and shows kinetic selectivity for the M3 (half-life: 4.97 hours) over the M2 receptor (half-life: 0.46 hour). It is selective for the β2-adrenoceptor over the β1 and β3 subtypes (3- and 6-fold, respectively) and shows dual antimuscarinic and β2-adrenoceptor functional activity in isolated guinea pig tissue (pIC50 in electrically stimulated trachea: 8.6; pEC50 in spontaneous tone isolated trachea: 8.8, r…