A single oral dose study in subjects with hepatic impairment and healthy control subjects. Subjects will stay at the clinical facility where interval blood samplings will be obtained and examined for drug effect.

Inclusion Criteria:

• Males and females, ages 18 to 70 years, inclusive
• BMI: 18.5 to 38 kg/m2
• Body weight great or equal to 45.5 kg
• Subjects with hepatic impairment
• Subjects with hepatic impairment must be on a stable dose of medication and/or treatment regimen
• Healthy subjects to the extent possible matched to the first four subjects with hepatic impairment with regard to age, body weight, and sex, as determined by no clinically significant deviation from normal in medical history, physical examination, ECGs, and clinical laboratory determinations

Exclusion Criteria:

• Any major surgery within 4 weeks of study drug administration
• Donation of blood to a blood bank or in a clinical study (except a screening visit) within 4 weeks of study drug administration (within 2 weeks for plasma only)
• Subject has required additional medication for hepatic encephalopathy within 12 months (6 months for severe hepatic impairment) prior to dosing
• Presence of severe ascites or edema in subjects, as judged by the PI