A Study Evaluating ABI-H0731+ Entecavir vs Entecavir Alone for the Treatment of Viremic HBeAg-positive Participants With Chronic Hepatitis B Virus Infection (cHBV)

Key Inclusion Criteria: * Male or female between ages 18 and 70 years * HBeAg-positive at screening * In good general health except for cHBV * HBV viral load ≥2×105 IU/mL * Hepatitis B surface antigen (HBsAg) \>1000 IU/mL at screening Key Exclusion Criteria: * Any prior treatment with lamivudine or telbivudine, previous treatment with an investigational agent for HBV other than ABI-H0731; or any other SOC treatment for \>4 weeks * Co-infection with HIV, hepatitis C virus (HCV), hepatitis E virus (HEV) or hepatitis D virus (HDV) * History or evidence of hepatic decompensation (including gastrointestinal bleeding or esophageal varices) at any time prior to or at time of screening * Clinically significant cardiac or pulmonary disease, chronic or recurrent renal or urinary tract disease, liver disease other than HBV, endocrine disorder, autoimmune disorder, diabetes mellitus requiring treatment with insulin or hypoglycemic agents, neuromuscular, musculoskeletal, or mucocutaneous conditions requiring frequent treatment, seizure disorders requiring treatment, or other medical conditions requiring frequent medical management or pharmacologic or surgical treatment that in the opinion of the Investigator or the Sponsor makes the participant unsuitable for the study * Previous treatment with an investigational agent for HBV other than ABI-H0731 in the last 6 months before screening * History of hepatocellular carcinoma (HCC) * Females who are lactating or pregnant or wish to become pregnant are excluded from the study * Exclusionary laboratory parameters at screening: * Platelet count \<100,000/mm3 * Albumin \<lower limit of normal (LLN) * Direct bilirubin \>1.2×upper limit of normal (ULN) * Alanine aminotransferase (ALT) \>10×ULN at screening * Serum alpha fetoprotein (AFP) ≥100 ng/mL. If AFP at Screening is \>ULN but \<100 ng/mL, participant is eligible if a hepatic imaging study prior to the initiation of study drug reveals no lesions suspicious of possible HCC * International Normalized Ratio (INR) \>1.5×ULN * Glomerular filtration rate (GFR) \<60 mL/min/1.73 m2 by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation