Treatment of Exacerbations of Asthma/COPD
MN-221 is a novel, highly selective ß2-adrenergic receptor agonist being developed for the treatment of exacerbations of asthma/COPD. We licensed MN-221 from Kissei Pharmaceutical Co., Ltd. Preclinical studies conducted in vitro and in vivo showed MN-221 to be highly selective for the ß2-adrenergic receptor. In these studies, the ß1-adrenergic receptor stimulating activity of MN-221 was less than that of other ß2-adrenergic receptor agonists in isolated rat atrium and in vivo cardiac function tests in rats, dogs and sheep, thereby suggesting that MN-221 may stimulate the heart less than older, less selective ß2-adrenergic receptor agonists. In addition, in vitro studies also suggested that MN-221 may act as only a partial ß1-adrenergic receptor agonist in cardiac tissue, while acting as a full ß2-adrenergic receptor in lung tissue. We believe that this improved receptor binding and functional selectivity may result in fewer cardiovascular side effects than are commonly observed with other ß2-adrenergic receptor agonists used to treat these conditions.