 A randomized, double-blind two-way crossover study of three cumulative doses of arformoterol 7.5 ug per nebulization and levalbuterol 0.63 mg per nebulization given over a one hour period, followed by a single open-label treatment day with three cumulative doses of arformoterol 15 ug in subjects 2-11 years of age with asthma. This study was previously posted by Sepracor Inc. In October 2009, Sepracor Inc. was acquired by Dainippon Sumitomo Pharma., and in October 2010, Sepracor Incs name was changed to Sunovion Pharmaceuticals Inc. 