Clinical Trial in Patients With Barth Syndrome- 4TAZPower

What this study involves

The registry says this study is recruiting. Individual locations may have different availability.

Study type

Interventional

Phase

Phase 4

Age range

5 years - 55 years

Sex eligible

Male

Healthy volunteers

Not accepted

Participants

48 Estimated

These are starting points, not an eligibility decision. The research team must review the full requirements.

About the research

Phase 3b/4, randomized, double-blind, parallel-group, placebo-controlled clinical trial to evaluate the efficacy, safety, and pharmacokinetics of a once daily SC injection of elamipretide in subjects with genetically confirmed BTHS for 72 weeks. The primary trial objective is to confirm the efficacy of elamipretide which is approved in the United States(FORZINITY™) under the accelerated approval based on an improvement in knee extensor muscle strength, an intermediate clinical endpoint.

Who may be able to participate?

The list below is the sponsor’s full registry wording. It can include conditions, prior treatment, test results and other requirements. A match in search does not mean you qualify.

Key Inclusion Criteria:

1. Willing and able to provide signed informed consent form (ICF) prior to participation in any trial-related procedures. If applicable, informed consent in writing from parent(s) or legally-acceptable representative(s) and, informed assent from subject (if age appropriate according to local requirements) should be provided.
2. Agrees to adhere to the trial requirements for the length of the trial.
3. Must have genetically confirmed Barth Syndrome (pathogenic variant in the TAZ gene)
4. Male aged ≥ 5 years at time of the Screening Visit
5. Left Ventricular Ejection fraction of ≥ 50% by 3-D Echocardiogram at the Screening Visit.
6. For subjects with a medical history of cardiomyopathy, must be on a stable regimen (unchanged and constant) of background heart failure medications for at least 3 months prior to the Screening Visit.
7. Able to administer Investigational Medicinal Product (IMP) or have an appropriate designee who can administer the IMP (i.e., a capable family member or a caregiver).
8. Subjects with female partners of childbearing potential must be willing to use a highly effective method of contraception (e.g., abstinence, dual method of contraception) from the date they sign the ICF until 28 days after the last dose of IMP.

Key Exclusion Criteria:

1. Unable to perform the required functional tests or undergo echocardiography.
2. History of solid organ transplant, except successful cardiac transplantation \> 12 months prior to screening, if, in the opinion of the Investigator, there is no evidence of organ rejection and post-transplant pharmacotherapy, is stable, and does not pose additional safety risk to participant.
3. Patients with an implantable cardioverter defibrillator (ICD) and with a known occurrence of ICD discharge in the 3 months prior to the Screening Visit.
4. Current placement on the waiting list for heart transplantation.
5. Hospitalization for heart failure within 6 months prior to the Screening Visit.
6. Any disease or medical condition that in the opinion of the Investigator would prevent the subject from successfully participating in the trial and reliably completing the assessments or might confound trial results.
7. Has a history of a systemic eosinophilic illness
8. Estimated Glomerular Filtration Rate (eGFR) of \< 30 mL/min at the Screening Visit (using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 formula for subjects \>16 years of age and the Schwartz 2009 formula for subjects 5-16 years of age).
9. Active malignancy or any other cancer from which the subject has been cancer-free for \< 2 years. Localized squamous or non-invasive basal cell skin carcinomas are allowed, if appropriately treated prior to Screening.
10. Participation in other investigational drug or device clinical trials within 30 days or 5 half-lives (whichever is longer) of Screening; or is currently enrolled in a non-interventional clinical trial that, in the opinion of the Investigator, may be potentially confounding to the results of the current trial.
11. History of allergic reaction to the IMP or any of its components.
12. Prior participation in any elamipretide trial or expanded access programs.

Treatment, groups and participation

The registry may describe treatments and study duration without a complete visit calendar. Ask the study team for the exact schedule, procedures, risks, costs and alternatives. Keep your usual care plan unless your treating clinician tells you otherwise.

Assignment

Random assignment

Masking

Quadruple masked

What researchers are measuring

Outcome measures describe what is being studied. They are not proof that a treatment works.

Primary measures

Secondary measures

Other measures

Research locations (4)

The overall study status and a local site’s status can differ. Confirm that location’s availability before traveling.

4 locations

Study team and timeline

Lead sponsor

Stealth BioTherapeutics Inc.

Study start

Jul 2, 2026 Actual

Primary completion

Sep 30, 2029 Estimated

Study completion

Nov 30, 2029 Estimated

First posted

Apr 15, 2026 Actual

Last updated

Nov 9, 2026 Actual

Official study contacts