The present invention is directed to novel polymorphic crystal forms of a 5-{2-{[6-(2,2-difluoro-2-phenylethoxy)hexyl]amino}-1-(R)-hydroxyethyl)-8-hydroxyquinolin-2(1H)-one, heminapadisylate. The invention is also directed to pharmaceutical compositions comprising said polymorphic crystal forms, methods of using them to treat respiratory diseases associated with ²2 adrenergic receptor activity and a process for preparing such polymophic crystal forms.