RecruitingPhase III/IVInterventional

A Phase IIIb/IV, randomized, double-blind, parallel-group, placebo-controlled, trial to evaluate the efficacy and safety of daily subcutaneous injections of elamipretide in patients with genetically confirmed Barth syndrome

This research study is investigating a new drug called elamipretide for individuals with Barth syndrome. The study wants to find out if daily injections of elamipretide are safe and work better than a dummy treatment (placebo) to help the body's cells produce energy in people with Barth syndrome. Elamipretide is thought to protect the 'powerhouses' of our cells (called mitochondria), which are important for overall energy. The drug has already received special approval in the United States for some patients. This study will help confirm how well it works and if it can be approved in other countries, including the UK. It involves males aged 5 and over with a confirmed diagnosis of Barth syndrome.

At a glance

Status

Recruiting

Phase

Phase III/IV

Sponsor

Stealth BioTherapeutics (United States)

Enrolment target

Start

24 Apr 2026

Estimated completion

30 Jun 2028

Barth Syndrome

What is this study about?

Barth syndrome is a rare condition that mainly affects boys and men. It can cause serious problems, especially with the heart and muscles, because the 'powerhouses' of your cells, called mitochondria, don't work correctly. Mitochondria are responsible for making energy for your body to function properly. This study is looking at a new drug called elamipretide, which is designed to help these mitochondria stay healthy and produce more energy.

The main goal of this study is to see if daily injections of elamipretide are effective in improving energy production in people with Barth syndrome who have a confirmed genetic diagnosis. Researchers also want to make sure the drug is safe and well-tolerated by participants. By giving elamipretide, the study hopes to reduce problems linked to a specific fat (called cardiolipin) that is often missing or damaged in individuals with Barth syndrome. This fat is very important for the mitochondria to work properly.

Currently, there are no specific approved treatments for Barth syndrome in many countries, including the UK. Although elamipretide has received a special, early approval in the United States for some patients, this study is crucial to gather more information. If the study shows good results for safety and effectiveness, it could mean that elamipretide becomes more widely available as a treatment option for Barth syndrome in the future. The results from this study could make a real difference to people living with the condition.

Key takeaways

The study investigates a new drug, elamipretide, for Barth syndrome.
It aims to check the safety and effectiveness of daily injections to improve cell energy.
Participants will be males aged 5 and over with genetically confirmed Barth syndrome.
The study is 'double-blind' and 'placebo-controlled' for fair results.
Taking part involves daily injections and regular clinic visits over approximately 72 weeks.
Results could lead to a new treatment option for Barth syndrome globally.

Who may be eligible?

This study is looking for males aged 5 years and older who have a medical diagnosis of Barth syndrome that has been confirmed by a genetic test. You must be willing to follow all the study rules and complete all the required tests.

Important medical checks include having a heart function test that shows your heart is pumping at least 50% of the blood from the main chamber. You also need to be able to do certain physical activity tests, like walking or standing up from a chair repeatedly. If you have any other serious health conditions that an expert doctor thinks would stop you from taking part safely or affect the study results, you might not be able to join.

Also, if you've recently taken part in another trial for a new drug or device, you might not be able to join this one immediately. If you have a female partner who could become pregnant, you'll need to agree to use effective contraception (birth control) throughout the study and for a short time afterwards.

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.

Am I male?
Am I 5 years old or older?
Do I have a genetic test confirming Barth syndrome?
Has my heart doctor said my heart's pumping well (at least 50%)?
Am I able to do some simple walking or movement tests?
Can I, or someone helping me, give injections under the skin every day?

Answer every question to see your result.

What does participation involve?

If you decide to take part, you'll be involved in this study for approximately 72 weeks, which is about a year and a half. A computer will randomly decide whether you receive the active study drug (elamipretide) or a dummy treatment (placebo). Neither you, your family, nor the study doctors will know which one you are getting – this is called 'double-blind' and helps ensure the results are fair.

Each day, you (or a family member/carer) will need to give yourself an injection under the skin. Throughout the study, you'll have regular visits to the clinic for various tests. These include blood tests, health checks, and functional tests to see how you're feeling and how your body is responding. These visits are important for monitoring your health and the effects of the treatment. Even if your treatment changes, you'll be encouraged to stay in the study so researchers can collect as much information as possible about Barth syndrome and the different treatments.

After the main study finishes, if it's considered suitable by the study doctor, you might have the option to join another part of the study where everyone receives the active drug. The study is expected to run from May 2026 until September 2029.

Potential risks and benefits

While you might not feel a direct benefit from taking part, the information gained from this study could help many other people with Barth syndrome in the future. You will also get regular health checks and tests, which can give you ongoing information about your general health. We do not know all possible side effects because it is a new drug, but researchers will carefully monitor your health and any potential side effects throughout the study. You might experience some discomfort from injections or the tests. Remember, joining a study is always your choice, and you are free to withdraw at any time without it affecting your usual medical care.

Locations (1)

Bristol Royal Hospital for Children
Approximate
Bristol, England

Common questions

What is Barth syndrome?

Barth syndrome is a rare genetic condition that mainly affects boys, causing problems with the heart, muscles, and immune system due to issues with the energy-producing parts of cells (mitochondria).

What is 'placebo-controlled'?

This means some participants will receive the active study drug, while others will receive an inactive 'dummy' substance. This helps researchers compare the effects accurately.

Who is funding this research?

The study is funded by Stealth BioTherapeutics Inc., a pharmaceutical company based in the USA.

Will I know if I'm getting the real drug or the placebo?

No, this is a 'double-blind' study, meaning neither you nor the study doctors will know which treatment you are receiving. This is to ensure fair and unbiased results.

What happens after the study ends?

After the main study, if suitable and approved by the doctor, you might be able to join an 'open-label' part of the study where everyone receives the active drug.

How to find out more

Parexel CTRS

CTRS-UK-Submissions@parexel.com - Official trial record

Always speak to your GP or specialist before deciding to take part in a study.