Due to adverse safety signals in Part 1 (HV)

Part 1 is a randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, and pharmacokinetics of single and multiple ascending doses of EDP-721 in healthy subjects.

Part 2 is a randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, pharmacokinetics and antiviral activity of EDP-721 in combination with EDP-514 in patients with chronic hepatitis B virus infection.

Part 1 (HV Population):

Inclusion Criteria:

• An informed consent document signed and dated by the subject.
• Healthy male and female subjects of any ethnic origin between the ages of 18 and 65 years, inclusive.

Exclusion Criteria:

• Clinically relevant evidence or history of illness or disease.
• Pregnant or nursing females.
• History of febrile illness within 7 days prior to the first dose of study drug or subjects with evidence of active infection.
• A positive urine drug screen at screening or Day -1.
• Current tobacco smokers or use of tobacco within 3 months prior to screening.
• Any condition possibly affecting drug absorption (e.g., gastrectomy, cholecystectomy).
• History of regular alcohol consumption.
• Receipt of any vaccine, an investigational agent or biological product within 28 days or 5 times the t½, whichever one is longer, prior to first dose.

Part 2 (CHB Population)

Inclusion Criteria (Nuc-Suppressed CHB Population)

• An informed consent document signed and dated by the subject.

• Healthy male and female subjects of any ethnic origin between the ages of 18 and 70 years, inclusive

• HBsAg detectable in serum/plasma at Screening and in the most recent HBsAg serum/plasma testing at least 6 months previously.

• HBV DNA levels:

  • A Screening HBV DNA level in serum/plasma that is \