A Study to Assess the Effect of Hepatic Function on the Pharmacokinetics and Safety of ASP1941

Inclusion Criteria: * Subjects with Moderate Hepatic Impairment * Agrees to practice highly effective birth control until 7 days post dose. If female, two years post-menopausal, surgically sterile, and not pregnant or lactating * Weights at least 45 kg * Body mass index between 18 and 34 kg/m2 * Meets criteria for moderate hepatic impairment defined by Child-Pugh method * Subjects with Normal Hepatic Function * Agrees to practice highly effective birth control until 7 days post dose. If female, two years post-menopausal, surgically sterile, and not pregnant or lactating * Weights at least 45 kg * Body mass index between 18 and 34 kg/m2 * Must have normal hepatic function defined by Child-Pugh method Exclusion Criteria: * Subjects with Moderate Hepatic Impairment * Has history or presence of biliary obstruction or biliary disease, hepatic encephalopathy, advanced ascites, portal hypertension, esophageal /gastric variceal bleeding, hepatocellular carcinoma, previous liver transplantation. * Has severe or moderate renal dysfunction * Known to be human immunodeficiency virus (HIV) positive * Has clinically significant history or presence of illness, malignancy or immunodeficiency * Has had a blood transfusion or donated / lost 450 mL of blood or more within 60 days of study drug administrations or donated plasma within 7 days prior to clinical check-in * Has history of alcoholism or drug/chemical/substance abuse within past 2 years * Subjects with Normal Hepatic Function * Has severe or moderate renal dysfunction * Known to be human immunodeficiency virus (HIV) positive * Has clinically significant history or presence of illness, malignancy or immunodeficiency * Has had a blood transfusion or donated / lost 450 mL of blood or more within 60 days of study drug administrations or donated plasma within 7 days prior to clinical check-in * Has history of alcoholism or drug/chemical/substance abuse within past 2 years