Novel anti-cholinergics in COPD.

Anti-cholinergics have been considered the first-choice bronchodilator therapy in the routine management of stable COPD. Muscarinic cholinergic receptors are expressed on most cell types and mediate cellular signalling via the natural ligand, acetylcholine. Antagonising cholinergic receptors may not only result in bronchodilation, but also have associated localised activity. Until recently the licensed anti-cholinergics were limited to ipatropium bromide, oxitropium bromide and tiotropium bromide; the latter being the only once-daily anti-cholinergic. With the patents expired or due to expire shortly several companies have reinitiated efforts to develop safer, long-acting agents potentially improving concordance and pharmaceutical marketing opportunities. The present article reviews a number of novel anti-cholinergics that have been recently licensed and those undergoing development, some in innovative delivery devices.