A Drug-Drug Interaction Study to Evaluate the Effects of Itraconazole, Carbamazepine, Quinidine and Fluconazole on the Pharmacokinetics and Safety of EDP-323.

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. * Screening body mass index (BMI) of 18 to 30 kg/m2 with a minimum body weight of50 kg * Female subjects of childbearing potential must agree to use two effective methods of contraception from the date of Screening until 30 days after the last dose of EDP-323. A male participant who has not had a vasectomy and is sexually active with a woman of childbearing potential must agree to use effective contraception from the date of Screening to 90 days after his last dose of study drug. 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 exceeding protocol limits * Participation in a clinical trial within 28 days prior to the first dose of study drug * For Part 2 and Part 3 participants, the following cardiovascular abnormalities: * QRS duration \>110 ms * Incomplete right bundle branch block or any complete bundle branch block * Heart rate \<40 or \>90 beats per minute (per vital sign capture while rested) * History of unexplained syncope, structural heart disease, or clinically significant arrhythmias * Personal or family history of long QT syndrome (genetically proven or suggested by sudden death of a close relative due to cardiac causes at a young age) or Brugada syndrome * PR interval \>220 ms or any 2nd or 3rd degree AV block * Ventricular pre-excitation * Other exclusions for Part 2 (carbamazepine) participants * Participants of Asian ancestry with HLA allele B\*1502 in this population * Platelets, white blood cell count or hemoglobin below the lower limit of normal, due to reported incidence of agranulocytosis and aplastic anemia with carbamazepine