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Safety, Tolerability, and Pharmacokinetics of MK-3508 in Healthy Adults for Treatment of Respiratory Syncytial Virus Infection

Fast replyInvestigationalNo placebo

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What is this trial about?

A plain-language summary of the goals, design and what participants do

The study involves a common lung infection called Respiratory syncytial virus infection, which can cause breathing problems especially in young children and older adults. The investigational medication being tested is identified by the code name MK-3508, and it is given as a liquid that is taken by mouth. A matching inactive product, referred to as placebo, is also used for comparison.

The purpose of the study is to determine whether a single dose of the medication is safe, well‑tolerated, and how it moves through the body. Participants receive one dose of either the study drug or the placebo and remain under observation for a short period. Blood samples are collected at several time points to measure the amount of drug present, which helps researchers understand absorption, distribution, and elimination without using complex medical jargon.

After dosing, participants stay for monitoring of any side effects and attend a few follow‑up visits where additional safety checks are performed. The overall time commitment is limited to a few days, and the procedures are designed to be straightforward and low‑risk for healthy volunteers.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

Step 1
Baseline assessments
You will undergo basic health checks, such as measuring blood pressure, heart rate, and a short physical exam. a blood sample will be taken to confirm that you are healthy enough to receive the study medication.
Step 2
Receive study medication
You will be given a sealed container that holds either mk-3508 or a matching placebo called ora blend sf. the study is designed so you will not know which one you receive.
Step 3
Take single oral dose
You will swallow a one‑time dose of 200 mg mk-3508 (or the placebo) as an oral suspension. the dose is taken by mouth only and is not repeated.
Step 4
Monitoring period
After taking the dose, you will remain in the clinic for several hours. staff will check your vital signs and ask about any symptoms you may feel. this monitoring helps ensure your safety.
Step 5
Blood sampling for pharmacokinetic analysis
A series of blood samples will be drawn at specific times after the dose, including a sample taken 24 hours later. these samples are used to measure how much mk-3508 is in your blood and how quickly it is cleared.
Step 6
Final assessment and discharge
After the last blood draw, a final health check will be performed. if no safety concerns are identified, you will be discharged from the study.

Who can join the trial?

3 criteria

Be a healthy man (no serious medical problems) who is between 18 and 45 years old.
Agree not to provide any donating sperm (giving sperm for a lab or clinic) while in the study.
Use a condom (a thin protective covering used during sex) or another reliable form of contraception (a method that prevents pregnancy) during the trial.

Who cannot join the trial?

10 criteria

You cannot join if you have a serious problem with any of these body systems: endocrine (hormone‑related), gastrointestinal (GI) (stomach and intestines), cardiovascular (heart and blood vessels), hematological (blood), hepatic (liver), immunological (immune system), renal (kidneys), respiratory (lungs), genitourinary (urinary and reproductive organs), or major neurological (brain and nerve) conditions such as stroke or ongoing seizures.
You cannot join if you regularly use cannabis or any illicit (illegal) drugs.
You cannot join if you are mentally or legally unable to give consent, have major emotional problems, or have had a serious psychiatric disorder (such as depression, anxiety, or psychosis) in the past five years.
You cannot join if you have a history of malignancy (cancer).
You cannot join if you have severe allergies (for example, to food, medicines, or latex) or have ever had an anaphylactic reaction (a severe, whole‑body allergic response) to prescription or over‑the‑counter medicines or foods.
You cannot join if a test shows you are positive for hepatitis B surface antigen, hepatitis C antibodies, or HIV (human immunodeficiency virus).
You cannot join if you cannot stop taking any medication—including prescription, nonprescription (over‑the‑counter), or herbal remedies—at least two weeks before the first dose and throughout the entire study.
You cannot join if you are a smoker.
You cannot join if you drink more than three alcoholic drinks each day.
You cannot join if you consume more than six servings of caffeinated beverages (such as coffee, tea, or soda) each day.

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Verified sites

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Verified
Advanced Technology Corporation
Liege, Belgium
Responsive
Universitair Ziekenhuis Gent
Gent, Belgium

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Investigated drugs

MK-3508 is an experimental medicine given as a liquid that you swallow. In this study it is being tested in healthy adult men to see if it is safe, how well people can tolerate it, and how the drug travels through the body after one dose. Researchers are measuring how quickly the medicine appears in the blood and how long it remains there. This drug is still under investigation and is not approved for treating any condition yet.

What is already known about the treatment

Ora Blend SF
It is an oral suspension used as a placebo in the study, meaning it contains no active drug and is taken by mouth just like the test medicine. The product is not approved for treating any disease and is listed only as an inert control in clinical research. Because it has no active ingredients, it has no therapeutic indication, no mechanism of action, and is classified simply as a placebo. Its purpose is to help compare safety and effects of the real drug.
MK-3508
It is given as a 200 mg oral suspension taken by mouth, and it is being studied as an experimental antiviral for respiratory syncytial virus (RSV) infection. The substance is still investigational and has not yet received marketing approval, with data coming from early‑phase clinical trials. It works by blocking a key viral enzyme needed for RSV to copy its genetic material, which stops the virus from multiplying. MK‑3508 belongs to the class of antiviral agents that target viral replication.

Investigated diseases

Respiratory syncytial virus infection - It is a viral infection that primarily affects the lining of the nose, throat, and lungs. The virus spreads through respiratory droplets and initially causes runny nose, cough, and fever. In many individuals the illness remains mild, but it can progress to inflammation of the small airways (bronchiolitis) and sometimes pneumonia. Symptoms usually peak within a week and then gradually improve as the immune system clears the virus. Young children, older adults, and people with weakened immune systems are more likely to develop the more extensive airway involvement.