GSK704838

GSK704838 (also known as GSK704838C) is a potent, pan-active muscarinic acetylcholine receptor (mAChR) antagonist developed by GSK. It was investigated as a long-acting bronchodilator for the once-daily treatment of chronic obstructive pulmonary disease (COPD). As a pan-active antagonist, it inhibits multiple subtypes of muscarinic receptors (M1, M2, M3, M4, and M5) to prevent acetylcholine-induced bronchoconstriction in the airways. Clinical development included Phase 1 studies to evaluate its safety, tolerability, and pharmacokinetics in comparison to tiotropium bromide. Development appears to have stalled after early-phase clinical trials.