AuthorisedTherapeutic exploratory (Phase II)Interventional

A Randomized, Double-Blind, Placebo-Controlled Dose-Ranging Study to Evaluate the Efficacy and Safety of Nalbuphine Extended-Release Tablets for the Treatment of Participants with Refractory Chronic Cough

A chronic cough is one that lasts for eight weeks or more. When standard medicines do not help, it is called a refractory chronic cough. This constant coughing can be exhausting and can disrupt daily life and sleep. This clinical trial is testing a new slow-release tablet called nalbuphine extended-release (ER). The main goal is to find out whether this medication can reduce the number of times a person coughs in a full 24-hour day. Participants will be placed into groups by chance. Some will receive the trial medicine at different strengths, while others will receive a placebo, which is a dummy pill with no active medicine. Neither you nor the study team will know which tablet you get. Researchers will monitor everyone closely for six weeks to check how well the tablets work and watch for any side effects.

At a glance

Status

Authorised

Phase

Therapeutic exploratory (Phase II)

Sponsor

Trevi Therapeutics Inc.

Enrolment target

Start

24 Sep 2026

Refractory Chronic Cough

What is this study about?

Coughing is a normal reflex that helps clear your airways, but a cough that will not go away can become a major problem. When a cough lasts for months and fails to clear up after trying standard treatments, doctors call it a 'refractory chronic cough'. Living with this condition can cause chest soreness, disturb your sleep, and make talking or working very tiring. Currently, there are limited options available to help people manage this kind of stubborn cough.

Researchers are running this study to look at a medicine called nalbuphine extended-release (ER). An 'extended-release' tablet is designed to dissolve slowly in your body, releasing the medicine steadily over time. Nalbuphine acts on specific signals in the nervous system to help calm down the urge to cough. The researchers want to discover if taking this tablet can lower how often participants cough throughout the day and night.

In this study, different doses of the medicine are being tested against a placebo (a dummy tablet that contains no real medicine). Comparing the active drug to a placebo helps doctors prove whether the improvements are truly caused by the new medicine. Finding an effective dose could lead to better treatments for people struggling with persistent coughs in the future.

Key takeaways

The trial tests a slow-release tablet called nalbuphine for stubborn, long-lasting coughs.
The study compares different strengths of the medicine against a dummy pill (placebo).
The main treatment period lasts for six weeks, with coughs counted over 24-hour periods.
Participation is entirely voluntary, and you can withdraw at any time.
The trial is open to adults aged 18 and older who meet the health criteria.

Who may be eligible?

This study is open to adults aged 18 and older of any gender who have been dealing with an unexplained, stubborn cough that has not responded to typical medical treatments.

To be considered, your cough must be chronic, which usually means it has lasted for at least two months without clearing up. You will also need to be well enough to attend study appointments and willing to take the tablets as directed by the clinic staff.

People with certain other lung conditions, active infections, or those taking medicines that might react badly with the study drug may not be able to take part. The study doctors will review your full medical history and current health before deciding if the study is safe for you.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

I am aged 18 or older.
I have had a continuous cough that has lasted for two months or more.
My cough has not improved after trying standard treatments.
I am able and willing to attend clinic visits over a six-week period.
I can take daily tablets and help track my coughing symptoms.

Answer every question to see your result.

What does participation involve?

If you decide to take part, you will be in the study for at least six weeks. Before you start, the study team will explain everything and ask you to sign a consent form. You will have a health check to make sure the trial is safe for you. You will then be randomly assigned to take either the study tablet (at one of several doses) or a matching dummy pill. You will take these tablets by mouth each day as instructed.

During the trial, you will need to attend regular clinic visits so the doctors can check your health and see how you are doing. A key part of the study involves measuring how often you cough over a 24-hour period, which may be tracked using a small wearable monitor or an electronic diary. You will also have standard checks like blood pressure measurements and will be asked about any side effects. After the six weeks of treatment end, there may be a follow-up check to make sure you remain well.

Potential risks and benefits

Taking part in this study may help reduce your cough, though there is no guarantee it will improve your symptoms, especially if you receive the dummy pill. The information gathered may also help doctors develop better treatments for other people with chronic coughs in the future. As with any medicine, there is a risk of side effects, which could include tiredness, nausea, or dizziness, and the study tests may take up some of your time. Your safety will be closely monitored throughout the trial, and you are free to leave the study at any time without giving a reason and without it affecting your regular NHS medical care.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Poland

Common questions

What is a placebo?

A placebo is a dummy tablet that looks identical to the real medicine but contains no active ingredients. It helps scientists see if the changes are truly caused by the study drug.

What does 'double-blind' mean?

It means neither you nor your study doctor will know whether you are taking the real medicine or the placebo. This keeps the study fair and prevents expectations from altering the results.

Will taking part cost me anything?

No, the study medicine and all related clinic visits are provided free of charge. Many trials also help cover reasonable travel expenses to and from the clinic.

Can I keep taking my usual medicines?

The study doctor will review all your current prescriptions to check which ones are safe to continue alongside the trial tablets.

What happens if I change my mind?

You can leave the study at any point. Your decision will never affect the quality of your regular care or your relationship with your normal healthcare team.