NCT05818124

Efficacy and Safety of Molnupiravir in Healthy Participants Inoculated With Experimental Influenza Virus (MK-4482-019)

A Phase 2a Double-Blind, Randomized, Placebo-Controlled Study to Evaluate the Efficacy and Safety of MK-4482 in Healthy Participants Inoculated With Experimental Influenza Virus

• Status: Completed
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 161 (actual)
• Sponsor: Merck Sharp & Dohme LLC · Industry
• Sex: All
• Age: 18 Years – 55 Years
• Healthy volunteers: Accepted

Summary

This is a phase 2a double-blind, randomized, placebo-controlled study to evaluate the efficacy and safety of molnupiravir (MK-4482) in healthy participants inoculated with experimental influenza virus. The primary hypotheses are that MK-4482 initiated 12 hours following intranasal inoculation of the influenza challenge virus reduces the peak viral load compared to placebo and that MK-4482 initiated 2 days following intranasal inoculation of the influenza challenge virus reduces the viral load area under the curve (AUC) compared to placebo.

Detailed description

This study has two parts. Part 1 is an open-label validation study, with a cohort of 20 untreated participants undergoing nasal inoculation with the A/France/759/21 \[H1N1\] strain on Day 0 to confirm viral infectivity and disease. Part 2 will be a randomized, double-blind placebo- and active-comparator-controlled study where participants will be inoculated on Day 0 with either the A/France/759/21 \[H1N1\] virus used in Part 1 or an alternative influenza virus. Part 2 will evaluate the antiviral efficacy, pharmacokinetics, and safety of MK-4482 in participants inoculated with the challenge virus.

Conditions

• Influenza Infection

Interventions

Type	Name	Description
DRUG	Molnupiravir	Four molnupiravir 200 mg capsules (800 mg total dose) taken twice daily by mouth.
DRUG	Placebo molnupiravir	Four placebo capsules matched to molnupiravir taken twice daily by mouth.
DRUG	Placebo oseltamivir	Placebo capsule matched to oseltamivir taken twice daily by mouth.
DRUG	Oseltamivir	One capsule of oseltamivir 75 mg taken twice daily by mouth.
BIOLOGICAL	Influenza A Virus	Influenza A challenge virus given once by intranasal administration at an inoculum concentration of between approximately 5 and 7 Log10 tissue culture infective dose 50% (TCID50/mL).

Timeline

• Start date: 2023-08-21
• Primary completion: 2024-06-28
• Completion: 2024-06-28
• First posted: 2023-04-18
• Last updated: 2025-08-06
• Results posted: 2025-08-06

Locations

1 site across 1 country: United Kingdom

Regulatory

• FDA-regulated drug study