A Clinical Trial to Evaluate [14C]-MK-4208/[14C]-TERN-701 in Healthy Adult Male Participants (MK-4208-002/TERN701-1016)

NCT07839000 | Completed Phase 1 FDA Drug

• 2 other identifiers: TERN701-1016MK-4208-002
• Study Type: interventional
• Target: 8
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of the study is to learn what happens to different forms of TERN-701 medications in a healthy person's body over time. Researchers will compare what happens to different forms of TERN-701 in a person's body over time. The goal of the study is to learn:

• What happens to different forms of TERN-701 in a person's body over time.
• The amount and number of different forms of TERN-701 that leave a person's body over time.

Conditions

Healthy

Outcome Measures

Primary Outcomes (32)

• Percentage of Total Amount of [14C]-Radiolabel Excreted into Urine per Sampling Interval (Aeurine,14C,t1-t2)

  Urine will be collected to determine the Aeurine,14C,t1-t2 of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Cumulative Percentage of Total Amount of [14C]-Radiolabel Excreted into Urine up to the Last Sampling Interval (Aeurine,14C)

  Urine will be collected to determine the Aeurine,14C of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Percentage of Total Amount of [14C]-Radiolabel Excreted into Feces per Sampling Interval (Aefeces,14C,t1-t2)

  Feces will be collected to determine the Aefeces,14C,t1-t2 of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Cumulative Percentage of Total Amount of [14C]-Radiolabel Excreted into Feces Up to the Last Sampling Interval (Aefeces,14C)

  Feces will be collected to determine the Aefeces,14C of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Percentage of Total Amount of [14C]-Radiolabel Excreted from Body per Sampling Interval (Aetotal, 14C, t1-t2)

  Urine and Feces will be collected to determine the Aetotal,14C,t1-t2 of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Cumulative Percentage of Total Excretion of [14C]-Radiolabel from the Body (Aetotal, 14C)

  Urine and Feces will be collected to determine the Aetotal,14C of radiolabeled \[14C\]-TERN-701. Calculated as, Aetotal,14C= Aeurine,14C +Aefeces,14C.

  Pre-dose and at designated time points up to 408 hours post dose

• Maximum Concentration Observed in Plasma (Cmax) of TERN-701 in Plasma

  Blood samples will be collected to determine the Cmax of TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Time to Maximum Concentration Observed in Plasma (Tmax) of TERN-701 in Plasma

  Blood samples will be collected to determine the Tmax of TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Apparent Terminal Half-Life (t1/2) of TERN-701 in Plasma

  Blood samples will be collected to determine the t1/2 of TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Area Under the Concentration-Time Curve from Time 0 to the Last Quantifiable Concentration (AUC0-last) of TERN-701 in Plasma

  Blood samples will be collected to determine the AUC0-Last of TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Area Under the Concentration-Time Curve from Time 0 Extrapolated to Infinity (AUC0-Inf) of TERN-701 in Plasma

  Blood samples will be collected to determine the AUC0-inf of TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Apparent Oral Clearance (CL/F) of TERN-701 in Plasma

  Blood samples will be collected to determine the CL/F of TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Apparent Volume of Distribution (Vz/F) of TERN-701 in Plasma

  Blood samples will be collected to determine the Vz/F of TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Total [14C]-Radiolabel in Plasma

  Blood samples will be collected to determine the Total \[14C\]-Radiolabel, calculated as the AUCinf of non-radiolabeled TERN-701 in plasma divided by the AUCinf of total \[14C\]-radiolabel in plasma.

  Pre-dose and at designated time points up to 408 hours post dose

• Tmax of Total [14C]-Radiolabel in Plasma

  Blood samples will be collected to determine the Tmax of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• t1/2 of Total [14C]-Radiolabel in Plasma

  Blood samples will be collected to determine the t1/2 of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• AUC0-last of Total [14C]-Radiolabel in Plasma

  Blood samples will be collected to determine the AUC0-last of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• AUC0-Inf of Total [14C]-Radiolabel in Plasma

  Blood samples will be collected to determine the AUC0-Inf of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Cmax of Total [14C]-Radiolabel in Plasma

  Blood samples will be collected to determine the Cmax of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Tmax of Total [14C]-Radiolabel in Whole Blood

  Blood samples will be collected to determine the Tmax of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• t1/2 of Total [14C]-Radiolabel in Whole Blood

  Blood samples will be collected to determine the t1/2 of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• AUC0-last of Total [14C]-Radiolabel in Whole Blood

  Blood samples will be collected to determine the AUC0-last of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• AUC0-Inf of Total [14C]-Radiolabel in Whole Blood

  Blood samples will be collected to determine the AUC0-Inf of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Cmax of Total [14C]-Radiolabel in Whole Blood

  Blood samples will be collected to determine the Cmax of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Cumulative Amount of Total [14C]-Radiolabel Excreted in Urine (Aeurine)

  Urine samples will be collected to determine the Aeurine of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Renal Clearence (CLr) of [14C] radioactivity

  Urine samples will be collected to determine the CLr of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Percent of Dose Excreted as Radioactivity in Urine (%Feurine) of [14C] radioactivity

  Urine samples will be collected to determine the %Feurine of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Cumulative Amount of Total [14C]-Radiolabel Excreted in Feces (Aefeces) of [14C] radioactivity

  Feces samples will be collected to determine the Aefeces of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Percent of Dose Excreted as Radioactivity in Feces (%Fefeces) of [14C] radioactivity

  Feces samples will be collected to determine the %Fefeces of radiolabeled \[14C\]-TERN-701.

  Pre-dose and at designated time points up to 408 hours post dose

• Percentage Area Under the Concentration-Time Curve (AUC) of [14C]-Radiolabel TERN-701 Metabolite in Plasma

  Blood samples will be collected to determine the Percentage of AUC of \[14C\]-radiolabel TERN-701 metabolite in plasma.

  Pre-dose and at designated time points up to 408 hours post dose

• Percentage of Administered Dose of [14C]-Radiolabel TERN-701 Metabolite in Feces

  Feces samples will be collected to determine the percentage of administered dose of \[14C\]-radiolabel TERN-701 metabolite in feces.

  Pre-dose and at designated time points up to 408 hours post dose

• Percentage of the [14C]-Radiolabel TERN-701 Metabolite in Urine

  Urine samples will be collected to determine the percentage of \[14C\]-radiolabel TERN-701 metabolite in urine.

  Pre-dose and at designated time points up to 408 hours post dose

Secondary Outcomes (6)

• Mean concentration of [14C]-TERN-701 Elimination

  Pre-dose and at designated time points up to 408 hours post dose

• Rate of Elimination of [14C]-TERN-701

  Pre-dose and at designated time points up to 408 hours post dose

• Whole Blood to Plasma Total [14C]-Radiolabel AUC Ratio

  Pre-dose and at designated time points up to 408 hours post dose

• Number of TERN-701 Metabolite in ≥10% of Total Exposure of [14C]-Radiolabel in Plasma

  Pre-dose and at designated time points up to 408 hours post dose

• Number of Participants Who Experience an Adverse Event (AE)

  Up to approximately 49 days

Study Arms (1)

[14C]-TERN-701

EXPERIMENTAL

Participants receive a single oral dose of radiolabeled TERN-701 (\[14C\]-TERN-701) on Day 1.

Drug: TERN-701

Interventions

TERN-701 DRUG

Oral Liquid radiolabeled with \[14C\]-TERN-701

Also known as: MK-4208, HS-10382

[14C]-TERN-701

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Has body mass index (BMI) ≥18.5 and ≤32.0 kg/m\^2
• Is in good health

You may not qualify if:

• Has history or presence of any medical condition or prior surgery that may impact typical absorption, distribution, metabolism, or excretion of the orally administered study drug (e.g., gastric bypass, gastrointestinal dysmotility, irritable or inflammatory bowel disease)
• Has history or laboratory evidence of hyperthyroidism (thyroid-stimulating hormone \[TSH\] \< lower limit of normal \[LLN\]) or hypothyroidism (TSH ≥8 mIU/L)
• Has history of cancer that has not been in complete remission for \> 5 years (except basal cell skin cancer or squamous cell skin cancer with a history of curative treatment and no recurrence for \> 1 year prior)
• Has history of dysphagia, aspiration, or other conditions that could potentially impede the ability to safely orally ingest the study drug per protocol
• Has history of incomplete bladder emptying with voiding (i.e., urinary retention) or recent history of awakening more than once at night to void
• Has usual habit of \< 1 or \> 3 bowel movements per day
• Has family history of long QT syndrome or of unexplained sudden death in a first-degree relative under 50 years of age
• Has documented congenital or acquired long QT syndrome

Sponsors & Collaborators

• Terns, Inc., a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA): lead

Study Sites (1)

Pharmaron CPC Inc

Baltimore, Maryland, 21201, United States

Location

Related Links

• Merck Clinical Trials Information

Study Officials

• Medical Director

  Merck Sharp & Dohme LLC

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 18, 2026
• First Posted: September 24, 2026
• Study Start: February 25, 2026
• Primary Completion: April 3, 2026
• Study Completion: April 3, 2026
• Last Updated: September 24, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will share

Locations

US (1)