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

A Non-Randomized, Open-Label, Drug-Drug Interaction Study to Evaluate the Effects of Itraconazole, Carbamazepine, Quinidine, and Fluconazole on the Pharmacokinetics and Safety of EDP-323 in Healthy Participants

The primary aim of the study is to assess the effect of itraconazole, carbamazepine, quinidine, and fluconazole individually on the pharmacokinetics and safety of EDP-323 in healthy adult participants. Each participant's duration in the study will be dependent upon which study part they are enrolled.

Study Overview

• Status: Completed
• Conditions: RSV Infection; Drug Drug Interaction (DDI)
• Intervention / Treatment: Drug: Itraconazole; Drug: EDP-323; Drug: EDP-323; Drug: EDP-323; Drug: carbamazepine; Drug: Quinidine; Drug: fluconazole

• Study Type: Interventional
• Enrollment (Actual): 48
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Texas
    • San Antonio, Texas, United States, 78209
      • ICON, plc

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: EDP-323 and itraconazole interaction (Part 1); Subjects will receive EDP-323 and itraconazole on respective dosing days	Drug: Itraconazole; Subjects will receive itraconazole QD Days 5-18; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 14; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 23; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 8
Experimental: EDP-323 and carbamazepine interaction (Part 2); Subjects will receive EDP-323 and carbamazepine on respective dosing days	Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 14; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 23; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 8; Drug: carbamazepine; Subjects will receive carbamazepine on Days 5 - 27
Experimental: EDP-323 and quinidine interaction (Part 3); Subjects will receive EDP-323 and quinidine on respective dosing days	Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 14; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 23; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 8; Drug: Quinidine; Subjects will receive quinidine on Days 5-12
Experimental: EDP-323 and fluconazole interaction (Part 4); Subjects will receive EDP-323 and fluconazole on respective dosing days	Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 14; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 23; Drug: EDP-323; Subjects will receive EDP-323 on Days 1 and 8; Drug: fluconazole; Subjects will receive fluconazole on Days 5-18

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Cmax of EDP-323 with and without coadministration with Itraconazole	Day 1 through Day 19
AUC of EDP-323 with and without coadministration with Itraconazole	Day 1 through Day 19
Cmax of EDP-323 with and without coadministration with Carbamazepine	Day 1 through Day 28
AUC of EDP-323 with and without coadministration with Carbamazepine	Day 1 through Day 28
Cmax of EDP-323 with and without coadministration with Quinidine	Day 1 through Day 13
AUC of EDP-323 with and without coadministration with Quinidine	Day 1 through Day 13
Cmax of EDP-323 with and without coadministration with fluconazole	Day 1 through Day 19
AUC of EDP-323 with and without coadministration with fluconazole	Day 1 through Day 19

Secondary Outcome Measures

Outcome Measure	Time Frame
Safety measured by adverse events	Up to 34 Days

Collaborators and Investigators

• Sponsor: Enanta Pharmaceuticals, Inc
• Investigators: Study Director: Enanta Pharmaceuticals, Inc, Enanta Pharmaceuticals, Inc

Study record dates

Study Major Dates

• Study Start (Actual): January 27, 2025
• Primary Completion (Actual): May 24, 2025
• Study Completion (Actual): June 1, 2025

Study Registration Dates

• First Submitted: February 21, 2025
• First Submitted That Met QC Criteria: February 21, 2025
• First Posted (Actual): February 26, 2025

Study Record Updates

• Last Update Posted (Estimated): July 1, 2025
• Last Update Submitted That Met QC Criteria: June 26, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: Drug Drug Interaction
• Additional Relevant MeSH Terms: Infections; RNA Virus Infections; Virus Diseases; Pneumovirus Infections; Paramyxoviridae Infections; Mononegavirales Infections; Respiratory Syncytial Virus Infections; Anti-Infective Agents; Antifungal Agents; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Hormones, Hormone Substitutes, and Hormone Antagonists; Enzyme Inhibitors; Central Nervous System Depressants; Sensory System Agents; Analgesics, Non-Narcotic; Analgesics; Neurotransmitter Agents; Anti-Arrhythmia Agents; Voltage-Gated Sodium Channel Blockers; Sodium Channel Blockers; Membrane Transport Modulators; Tranquilizing Agents; Psychotropic Drugs; Steroid Synthesis Inhibitors; Hormone Antagonists; Cytochrome P-450 Enzyme Inhibitors; Antimalarials; Antiprotozoal Agents; Antiparasitic Agents; Adrenergic Agents; Anticonvulsants; Antimanic Agents; Cytochrome P-450 CYP3A Inhibitors; Cytochrome P-450 CYP2D6 Inhibitors; Adrenergic Antagonists; Muscarinic Antagonists; Cholinergic Antagonists; Cholinergic Agents; Cytochrome P-450 CYP2C9 Inhibitors; Cytochrome P-450 Enzyme Inducers; Cytochrome P-450 CYP3A Inducers; Adrenergic alpha-Antagonists; 14-alpha Demethylase Inhibitors; Cytochrome P-450 CYP2C19 Inhibitors; Itraconazole; Fluconazole; Carbamazepine; Quinidine
• Other Study ID Numbers: EDP 323-005

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No