The main purpose of this study is to compare how one 50mg tablet of SB-497115 is broken down in the body by healthy subjects versus subjects with mild, moderate or severe liver problems. The study is also being done to 1) check on how well the study drug is tolerated by healthy subjects versus those with liver problems and 2) to check if liver impairment affects how the study drug binds to protein in the blood.

Inclusion criteria:

• Healthy or have liver impairment
• Females(the following requirement applies only if able to have children): agree to doctor approved birth control methods, or partner has had a vasectomy.
• Body mass index (BMI-within acceptable range)
• Negative drug, alcohol, and HIV tests

Exclusion criteria:

• Taking a medication or therapy not approved by the study doctor
• Rapidly changing liver function
• Kidneys not working well
• Drug or alcohol abuse within past 6 months
• Used an investigational drug in the past 30 days
• Females that are pregnant or nursing
• Have active hepatitis B or C
• History of blood disorders
• History of various heart conditions (as noted by study doctor)
• Blood clotting problems or blood abnormalities