A Study of AB-161 Following Oral Administration in Healthy Subjects

To evaluate the safety and tolerability of AB-161 following oral administration of single doses to healthy subjects To be assessed by monitoring - The frequency and severity of treatment-emergent adverse events (TEAEs) will be coded to the Medical Dictionary for Regulatory Activities (MedDRA) - Discontinuations due to adverse events (AEs) will be coded to the Medical Dictionary for Regulatory Activities (MedDRA) - Laboratory (Clinical Chemistry, Hematology, Coagulation and Urinalysis): blood sample collection and analysis by pathology lab - 12-lead Electrocardiogram (ECG) - Vital sign abnormalities (systolic/diastolic BP - sphygmomanometer/blood pressure monitor; heart rate - stethoscope; respiratory rate - pulse oximeter; body temperature - thermometer) The Investigator will assess intensity for each AE and SAE reported during the study using the Division of AIDS (DAIDS) Table for Grading the Severity of Adult and Pediatric Adverse Events (DAIDS Table)

The study drug AB-161 is being developed as a potential new treatment for chronic hepatitis B (CHB) infection. This is the first clinical study where AB-161 will be given to humans. The main goal is to determine whether AB-161 is safe and well tolerated when given at different doses. The levels of the study drug will also be measured at different times. The study may have up to 9 cohorts with 10 healthy volunteers per cohort. The first cohort will start with a conservative dose and dose escalation for each cohort will only occur after review of safety, tolerability, and pharmacokinetics data. The first two subjects in each cohort (except for the food effect panel) will be dosed in a 1:1 ratio of AB-161 to placebo. If the safety profile of the first two subjects is acceptable, the remainder of the subjects will be dosed in a 7:1 ratio of AB-161 to placebo. A separate dosing panel (food effect panel) will evaluate the effect food has on how AB-161 behaves in the body. Subjects will be dosed in a 8:2 ratio of AB-161 to placebo in the food effect panel. The food effect panel will be conducted after cohort 5 at a dose level considered safe and well tolerated.