A Clinical Study of MK-4482 in Chinese Healthy Male Participants (MK-4482-009)

An Open-label Study to Characterize the Pharmacokinetics, Safety and Tolerability of Single and Multiple Oral Doses of MK-4482 in Chinese Healthy Male Participants

The goal of the study is to learn what happens to MK-4482 after single and multiple doses in healthy Chinese participants over time. Researchers also want to learn about the safety of MK-4482, including how well people tolerate it.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Drug: MK-4482

• Study Type: Interventional
• Enrollment (Actual): 16
• Phase: Phase 1

Contacts and Locations

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100191
      • Peking University Third Hospital (Site 0001)

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

The main inclusion criteria include but are not limited to the following:

- Has a Body Mass Index (BMI) of 19 to 24 weight (kg)/height (m)2, inclusive, and body weight of ≥ 50 kg at the screening visit.

Exclusion Criteria:

The main exclusion criteria include but are not limited to the following:

• Has a history of clinically significant abnormalities or diseases.
• Has history of cancer.
• Has a history of significant multiple and/or severe allergies.
• Had any major surgery.
• Has participated in another investigational study within 3 months prior to the screening visit.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: MK-4482; Participants in period 1 received, MK-4482 800 mg single oral dose in the morning on Day 1. Participants in period 2 received, MK-4482 800mg oral dose administered every 12 hours (Q12H) on Day 1 through Day 6 for11 doses.	Drug: MK-4482; Participants in period 1 received, MK-4482 800 mg single oral dose in the morning on Day 1. Participants in period 2 received, MK-4482 800mg oral dose administered every 12 hours (Q12H) on Day 1 through Day 6 for11 doses.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Maximum Observed Plasma Concentration (Cmax) After Single Oral Dose of MK-4482 in Period 1	Cmax of N-hydroxycytidine (NHC) after a single oral dose of MK-4482 in period 1.	At designated time points up to 72 hours post-dose
Time to Reach Maximum Observed Plasma Concentration (Tmax ) After Single Oral Dose of MK-4482 in Period 1.	Tmax of NHC following single oral dose of MK-4482 in period 1.	At designated time points up to 72 hours post-dose
Elimination Half Life (T1/2) After Single Oral Dose of MK-4482 in Period 1	T1/2 is defined as the time required for the concentration or amount of NHC in the body to be reduced by one-half after a single oral dose of MK-4482 in period 1.	At designated time points up to 72 hours post-dose
Apparent Total Clearance (CL/F) After Single Oral Dose of MK-4482 in Period 1	CL/F of NHC from plasma after single oral dose of MK-4482 in period 1.	At designated time points up to 72 hours post-dose
Apparent Volume of Distribution (Vz/F) After Single Oral Dose of MK-4482 in Period 1	Vz/F of NHC during terminal phase after single oral dose of MK-4482 in period 1.	At designated time points up to 72 hours post-dose
Area Under the Plasma Concentration-time Curve From Time 0 to 12 Hours Post-dose (AUC0-12hr) After Single Oral Dose of MK-4482 in Period 1	This is a measure of the average amount of NHC in the plasma over a period of 12 hours after single oral dose of MK-4482 in period 1.	At designated time points up to 72 hours post-dose
Area Under the Plasma Concentration-time Curve From Time Zero to Last Measurable Concentration (AUC0-last) After Single Oral Dose of MK-4482 in Period 1	AUC0-last of NHC following a single oral dose of MK-4482 in period 1.	At designated time points up to 72 hours post-dose
Area Under The Plasma Concentration Versus Time Curve From Time Zero (pre-dose) to Extrapolated Infinite Time (AUC0-inf) After Single Oral Dose of MK-4482 in Period 1	AUC0-inf of NHC after single oral dose of MK-4482 in period 1.	At designated time points up to 72 hours post-dose
The Maximum Observed Plasma Concentration (Cmax) After Multiple Oral Doses of MK-4482 in Period 2	Cmax of NHC after multiple oral doses of MK-4482 in period 2.	At designated time points up to 72 hours post-dose
Time to Reach Maximum Observed Plasma Concentration (Tmax ) After Multiple Oral Doses of MK-4482 in Period 2	Tmax of NHC following multiple oral doses of MK-4482 in period 2.	At designated time points up to 72 hours post-dose
Elimination Half Life (T1/2) After Multiple Oral Doses of MK-4482 in Period 2	T1/2 is defined as the time required for the concentration or amount of NHC in the body to be reduced by one-half after multiple oral doses of MK-4482 in period 2.	At designated time points up to 72 hours post-dose
Clearance at Steady State (CLss/F) After Multiple Oral Doses of MK-4482 in Period 2	CLss/F of plasma NHC following multiple doses of MK-4482 in period 2.	At designated time points up to 72 hours post-dose
Apparent Volume of Distribution (Vz/F) After Multiple Oral Doses of MK-4482 in Period 2	Vz/F of NHC during terminal phase after multiple doses of MK-4482 in period 2.	At designated time points up to 72 hours post-dose
Area Under the Plasma Concentration-time Curve From Time 0 to 12 Hours Post-dose (AUC0-12hr) After Multiple Oral Doses of MK-4482 in Period 2	This is a measure of the average amount of NHC in the plasma over a period of 12 hours after multiple oral doses of MK-4482 in period 2.	At designated time points up to 72 hours post-dose
The Minimum Concentration (Ctrough) After Multiple Oral Doses of MK-4482 in Period 2	Ctrough of NHC that occurred following multiple doses of MK-4482 in period 2.	At designated time points up to 72 hours post-dose
Accumulation Ratio on Cmax After Multiple Oral Doses of MK-4482 in Period 2	The maximum concentration at steady state following multiple doses of MK-4482 in period 2 divided by the maximum concentration following the initial dosing in Period 1.	At designated time points up to 72 hours post-dose
Accumulation Ratio on AUC0-12hr After Multiple Oral Doses of MK-4482	The AUC0-12hr at steady state following multiple doses of MK-4482 in period 2 divided by the AUC0-12hr following the initial dosing in Period 1.	At designated time points up to 72 hours post-dose

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants Who Experience an Adverse Event (AE)	An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who experience an AE will be reported.	Up to ~ 5.5 weeks
Number of Participants Who Discontinue Study Treatment Due to an AE	An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who discontinue study treatment due to an AE will be reported.	Up to ~ 5.5 weeks

Collaborators and Investigators

• Sponsor: Merck Sharp & Dohme LLC
• Investigators: Study Director: Medical Director, Merck Sharp & Dohme LLC

Publications and helpful links

General Publications

• Zhu J, Zhang D, Liu Z, Yan B, Zang Y, Zhao W, Sun F, Maas BM, Cheng MH, Stoch SA, Li H. Pharmacokinetics and Safety of Single and Multiple Doses of Molnupiravir in Healthy Male Chinese Adults: An Open-Label, Fixed Sequence, Phase 1 Study. Clin Transl Sci. 2026 Apr;19(4):e70481. doi: 10.1111/cts.70481.

Helpful Links

• Merck Clinical Trials Information

Study record dates

Study Major Dates

• Study Start (Actual): June 28, 2023
• Primary Completion (Actual): August 5, 2023
• Study Completion (Actual): August 5, 2023

Study Registration Dates

• First Submitted: February 4, 2025
• First Submitted That Met QC Criteria: February 4, 2025
• First Posted (Actual): February 10, 2025

Study Record Updates

• Last Update Posted (Actual): April 16, 2026
• Last Update Submitted That Met QC Criteria: April 13, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Coronavirus Disease (COVID-19)
• Additional Relevant MeSH Terms: Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; COVID-19; Anti-Infective Agents; Antiviral Agents; molnupiravir
• Other Study ID Numbers: 4482-009; MK-4482-009 (Other Identifier: MSD)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: http://engagezone.msd.com/doc/ProcedureAccessClinicalTrialData.pdf

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.: Yes