- Subjects with severe renal failure at the Screening-Ext visit (as defined by glomerular filtration rate < 30 mL/min/1.73 m2 by Cockroft und Gault calculation • Clinically significant laboratory abnormalities, confirmed by repeat measurement, which may interfere with the assessment of safety and / or efficacy of the study drug, other than hyperglycemia and glycosuria at the Screening-Ext Visit.