This is a non-randomized, 2-part, open-label, drug-drug interaction (DDI) study to evaluate the effect of concomitant administration of itraconazole or rifampin on the pharmacokinetics and safety of EDP-305 in healthy human volunteers.

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 55 years, inclusive.
• Female subjects must be of non-childbearing potential.

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.
• Participation in a clinical trial within 30 days prior to the first dose of study drug.