GSK2485852 is a Hepatitis C NS5B site IV non-nucleoside polymerase inhibitor being developed for the treatment of chronic HCV infection. HBI115040 is the first administration of GSK2485852 in humans to establish the initial safety, tolerability, pharmacokinetic, and antiviral profile. The study design is a fusion of single and repeat dosing cohorts in HCV infected subjects to evaluate the safety, pharmacokinetics, and antiviral activity of GSK2485852.