A Drug-Drug Interaction Study of Itraconazole and Opevesostat (MK-5684) in Healthy Adult Male Participants (MK-5684-017)

June 24, 2026 updated by: Merck Sharp & Dohme LLC

A Phase 1, Open-Label, Fixed-Sequence Study to Evaluate the Effects of Multiple Doses of Itraconazole on the Single-Dose Pharmacokinetics of MK-5684 in Healthy Adult Male Participants

Researchers have designed a study medicine called opevesostat as a new way to treat prostate cancer.

The purpose of this study is to learn what happens to opevesostat in a person's body over time (a pharmacokinetic or PK study). Researchers will compare what happens to opevesostat in the body when it is given with and without another medicine called itraconazole.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

14

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Nebraska
      • Lincoln, Nebraska, United States, 68502
        • Celerion, Inc. ( Site 0001)

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

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 ≥18.0 and ≤32.0 kg/m^2
  • Is medically healthy with no clinically significant medical history

Exclusion Criteria:

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

  • Has a history or presence of any of the following: adrenal insufficiency; hepatic or renal impairment; clinically significant hypotension, cardiac arrhythmia, cardiac conduction abnormalities, or recurrent unexplained syncopal events; second- or third-degree atrioventricular heart block; clinically significant sick sinus syndrome; any systemic fungal infection; chronic infection; glaucoma; hypothyroidism; stomach ulcer; ocular herpes simplex; ventricular dysfunction or risk factors for Torsades de Pointes (e.g., heart failure, cardiomyopathy, family history of Long QT Syndrome)
  • Has a history of cancer (malignancy)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Opevesostat Period 1
On Day 1, a single dose of opevesostat will be administered under fed conditions. A single dose of steroid replacement (prednisone and fludrocortisone) will be administered under fed conditions approximately 4.5 hours after opevesostat dosing.
Drug: Opevesostat
Administered via oral film-coated tablet
Other Names:
  • MK-5684
  • ODM-208
Drug: Prednisone
Administered via oral tablet
Drug: Fludrocortisone acetate
Administered via oral tablet
Experimental: Opevesostat Period 2
There will be a washout of at least 5 days between opevesostat dosing in Period 1 and the first itraconazole dosing in Period 2. In Period 2, itraconazole will be administered once daily (QD) for 9 consecutive days with a single dose of opevesostat coadministered on Day 4 under fed conditions. Steroid replacement (prednisone and fludrocortisone) will be administered under fed conditions QD on Days 4 through 6, approximately 4.5 hours after opevesostat and/or itraconazole dosing.
Drug: Opevesostat
Administered via oral film-coated tablet
Other Names:
  • MK-5684
  • ODM-208
Drug: Prednisone
Administered via oral tablet
Drug: Fludrocortisone acetate
Administered via oral tablet
Drug: Itraconazole
Administered via oral capsule

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Area under the concentration versus time curve from 0 to infinity after single dosing (AUC0-inf) of opevesostat
Time Frame: Predose, and at designated timepoints up to 144 hours post-dose
Blood samples will be collected to determine the AUC0-inf of opevesostat.
Predose, and at designated timepoints up to 144 hours post-dose
Area under the concentration versus time curve from 0 to last quantifiable sample (AUC0-last) of opevesostat
Time Frame: Predose, and at designated timepoints up to 144 hours post-dose
Blood samples will be collected to determine the AUC0-last of opevesostat.
Predose, and at designated timepoints up to 144 hours post-dose
Maximum concentration (Cmax) of opevesostat
Time Frame: Predose, and at designated timepoints up to 144 hours post-dose
Blood samples will be collected to determine the Cmax of opevesostat.
Predose, and at designated timepoints up to 144 hours post-dose
Time to Maximum concentration (Tmax) of opevesostat
Time Frame: Predose, and at designated timepoints up to 144 hours post-dose
Blood samples will be collected to determine the Tmax of opevesostat.
Predose, and at designated timepoints up to 144 hours post-dose
Apparent terminal half-life (t1/2) of opevesostat
Time Frame: Predose, and at designated timepoints up to 144 hours post-dose
Blood samples will be collected to determine the t1/2 of opevesostat.
Predose, and at designated timepoints up to 144 hours post-dose
Apparent Clearance (CL/F) of opevesostat
Time Frame: Predose, and at designated timepoints up to 144 hours post-dose
Blood samples will be collected to determine the CL/F of opevesostat.
Predose, and at designated timepoints up to 144 hours post-dose
Apparent volume of distribution during terminal phase (Vz/F) of opevesostat
Time Frame: Predose, and at designated timepoints up to 144 hours post-dose
Blood samples will be collected to determine the Vz/F of opevesostat.
Predose, and at designated timepoints up to 144 hours post-dose

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of participants who experience one or more adverse events (AEs)
Time Frame: Up to approximately 28 days
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. The number of participants who experience an AE will be reported.
Up to approximately 28 days
Number of participants who discontinue study intervention due to an AE
Time Frame: Up to approximately 28 days
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. The number of participants who discontinue study intervention due to an AE will be reported.
Up to approximately 28 days

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Merck Sharp & Dohme LLC

Investigators

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

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 11, 2026

Primary Completion (Actual)

June 1, 2026

Study Completion (Actual)

June 18, 2026

Study Registration Dates

First Submitted

April 17, 2026

First Submitted That Met QC Criteria

April 17, 2026

First Posted (Actual)

April 23, 2026

Study Record Updates

Last Update Posted (Actual)

June 25, 2026

Last Update Submitted That Met QC Criteria

June 24, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 5684-017
  • MK-5684-017 (Other Identifier: MSD)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

https://trialstransparency.msdclinicaltrials.com/pdf/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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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