A Study to Investigate the Effects of Zelicapavir (EDP-938) on QTc Interval in Healthy Adults

Phase 1, Randomized, Double-Blind Four-Period Crossover, Thorough QT/QTc Study to Evaluate the Effects of EDP-938 on Cardiac Repolarization in Healthy Adults

The purpose of the study is to assess the effect of a therapeutic and supratherapeutic dose of zelicapavir on the corrected cardiac QT interval relative to a placebo and positive control in healthy participants.

Study Overview

• Status: Completed
• Conditions: RSV Infection; QTc Interval
• Intervention / Treatment: Drug: zelicapavir (therapeutic dose); Drug: zelicapavir (supratherapeutic dose); Drug: Placebo; Drug: moxifloxacin

• Study Type: Interventional
• Enrollment (Actual): 72
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Kansas
    • Lenexa, Kansas, United States, 66219
      • ICON
  • Texas
    • San Antonio, Texas, United States, 78290
      • ICON Early Phase, LLC

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.
• Male or female individuals who are 18 to 65 years of age, inclusive
• Screening body mass index (BMI) of 18 to 30 kg/m2 with a minimum body weight of 50 kg
• Heterosexually active male participants and their female partners of childbearing potential must agree to use 2 effective birth control methods for the duration of the study and for 90 days after the last dose of study intervention.
• Females of childbearing potential must agree to use 2 effective birth control methods for the duration of the study and for 30 days after the last dose of study intervention.

Exclusion Criteria:

• Clinically relevant evidence or history of illness or disease
• Clinically relevant risk factors for cardiovascular abnormalities
• 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
• Infection with HIV, HBV, HCV, or SARS CoV 2
• Any condition possibly affecting drug absorption (e.g., gastrectomy, cholecystectomy)
• Before the first dose of study intervention, participant has received any vaccine, an investigational agent or biological product within 28 days or 5 times the terminal half-life (t½), whichever is longer
• A positive urine drug screen at Screening or Day -1
• Current tobacco smokers or use of tobacco within 3 months prior to Screening
• History of regular alcohol consumption

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: zelicapavir Dose 1 (therapeutic dose); All participants will receive 4 study interventions. The study interventions will be administered during separate treatment periods starting on Days 1, 9, 17, and 25.	Drug: zelicapavir (therapeutic dose); Subjects will receive zelicapavir (TD) once per treatment period.; Other Names: EDP-938
Experimental: zelicapavir Dose 2 (supratherapeutic dose); All participants will receive 4 study interventions. The study interventions will be administered during separate treatment periods starting on Days 1, 9, 17, and 25.	Drug: zelicapavir (supratherapeutic dose); Subjects will receive zelicapavir (SD) once per treatment period.; Other Names: EDP-938
Placebo Comparator: placebo; All participants will receive 4 study interventions. The study interventions will be administered during separate treatment periods starting on Days 1, 9, 17, and 25.	Drug: Placebo; Subjects will receive zelicapavir matching placebo once per treatment period.
Experimental: moxifloxacin; All participants will receive 4 study interventions. The study interventions will be administered during separate treatment periods starting on Days 1, 9, 17, and 25.	Drug: moxifloxacin; Subjects will receive moxifloxin once per treatment period.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Time-matched, placebo-corrected change-from-baseline QTc based on the Fridericia correction QTcF (ΔΔQTcF) after TD and SD of Zelicapavir	Up to 24 hours post dose

Secondary Outcome Measures

Outcome Measure	Time Frame
Time-matched, placebo-corrected, change-from-baseline non-QT intervals after TD and SD of Zelicapavir	Up to 24 hours post dose
Time-matched, placebo-corrected, change-from-baseline HR after TD and SD of Zelicapavir	Up to 24 hours post dose
Concentration-QTc analysis based on the relationship between plasma concentrations of zelicapavir and ΔΔQTcF after a TD and SD of zelicapavir	Up to 96 hours post dose
Cmax of zelicapavir	Up to 96 hours post dose
Tmax of zelicapavir	Up to 96 hours post dose
t1/2 of zelicapavir	Up to 96 hours post dose
Vd/F of zelicapavir	Up to 96 hours post dose
CL/F of zelicapavir	Up to 96 hours post dose
ΔΔQTcF after moxifloxacin dosing	Up to 24 hours post dose
Safety measured by adverse events	Up to Day 33

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): July 15, 2024
• Primary Completion (Actual): February 2, 2025
• Study Completion (Actual): February 25, 2025

Study Registration Dates

• First Submitted: August 27, 2024
• First Submitted That Met QC Criteria: September 13, 2024
• First Posted (Actual): September 19, 2024

Study Record Updates

• Last Update Posted (Actual): July 28, 2025
• Last Update Submitted That Met QC Criteria: July 24, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Infections; RNA Virus Infections; Virus Diseases; Pneumovirus Infections; Paramyxoviridae Infections; Mononegavirales Infections; Respiratory Syncytial Virus Infections; Anti-Bacterial Agents; Anti-Infective Agents; Antineoplastic Agents; Molecular Mechanisms of Pharmacological Action; Enzyme Inhibitors; Topoisomerase Inhibitors; Topoisomerase II Inhibitors; Moxifloxacin
• Other Study ID Numbers: EDP 938-008

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