Human study PLS-00106

Long-term efficacy and safety of elamipretide in patients with Barth syndrome: 168-week open-label extension results of TAZPOWER.

Single-arm trial · Not reported participants enrolled

Version 1 · published November 8, 2026 · evidence through November 8, 2026 · research snapshot 2026.1.1 · methodology ev-1 · Automated assessment by AI (claude-opus-5-5 and claude-sonnet-5-5), not reviewed by a person.

Only the abstract was available. Essential methods may be missing, which limits what can be judged.

Reports of this study

Every publication, registration and abstract describing this one study. Participants are counted once.

Long-term efficacy and safety of elamipretide in patients with Barth syndrome: 168-week open-label extension results of TAZPOWER.primary · Genetics in medicine : official journal of the American College of Medical Genetics · 2024-04-08 · PMID 38602181 · DOI
A Trial to Evaluate Safety, Tolerability and Efficacy of Elamipretide in Subjects With Barth Syndromeregistry entry · NCT03098797 (COMPLETED, results posted, planned enrollment 12)

Design and participants

Design: Single-arm trial
Population: Patients with Barth syndrome who had completed the 28-week randomized, double-blind, placebo-controlled phase of TAZPOWER and entered the 168-week open-label extension.
Conditions: Barth syndrome
Setting: Open-label extension of a phase 2/3 interventional trial. Sites are not stated.
Planned enrollment (registry): Not reported
Enrolled: Not reported
Randomized: Not reported
Completed follow-up: 8
Funding: Not stated. PubMed tags the article 'Research Support, Non-U.S. Gov't' without naming the funder.
Authors’ conflicts: Not stated in the record.

Intervention and comparator

What each group received. Related peptides, analogs and combinations are never treated as the compound itself.

Elamipretide open-label extension (intervention) · elamipretide · Elamipretide continued daily during the open-label extension · subcutaneous · 168-week open-label extension · 10 assigned

What the authors reported

As stated in the sources. This is the authors’ account, not Peptide Library’s assessment.

Safety and tolerability

primary outcome · safety · Through the 168-week open-label extension · Adverse events

Elamipretide open-label extension: narrative — Elamipretide was well tolerated; injection-site reactions were the most common adverse events.

6-minute walk test distance

secondary outcome · patient-important · All OLE time points, through week 168 · Change from open-label extension baseline in 6MWT distance (m)

Elamipretide open-label extension: change from baseline 96.1, p = 0.003 — Significant improvement from OLE baseline at all time points, cumulative improvement of 96.1 m at week 168.

BTHS-SA Total Fatigue score

secondary outcome · patient-important · All OLE time points · Change from baseline in BarTH Syndrome Symptom Assessment Total Fatigue score

Elamipretide open-label extension: narrative — Mean fatigue scores were below baseline (improved) at all OLE time points.

Muscle strength

unclear outcome · patient-important · Not stated · Muscle strength assessment (method not stated)

No results reported.

Physician- and patient-assessed outcomes

unclear outcome · patient-important · Not stated · Physician- and patient-assessed global outcomes (instruments not stated)

No results reported.

3D echocardiographic left ventricular volumes

unclear outcome · surrogate · Baseline to week 168 · 3D left ventricular stroke, end-diastolic and end-systolic volumes

Elamipretide open-label extension: narrative — LV stroke, end-diastolic and end-systolic volumes improved, with significant trends for improvement to week 168.

MLCL/CL ratio

unclear outcome · surrogate · Not stated · Monolysocardiolipin to cardiolipin ratio biomarker

Elamipretide open-label extension: narrative — MLCL/CL values showed improvement, correlating with important clinical outcomes.

Adverse events

Injection-site reactions · Elamipretide open-label extension: Not reported participants

Monitoring: Safety and tolerability were the primary endpoints of the open-label extension. Monitoring methods are not described in the abstract.

The authors concluded (paraphrased): The authors concluded that long-term elamipretide was associated with sustained tolerability and efficacy in Barth syndrome, with improvements in functional assessments and cardiac function.

Peptide Library’s assessment

An automated assessment, made by AI separately from the authors’ conclusions and not reviewed by a person. How risk of bias is assessed.

Limitations

no control group: The 168-week extension results come from a single open-label group with no concurrent placebo comparison.
small or imprecise: Only 10 patients entered the extension and 8 reached week 168, so estimates are highly imprecise.
inadequate blinding: Open-label treatment with effort-dependent outcomes (6MWT, self-reported fatigue) risks expectation effects.
incomplete follow up: Two of the 10 patients did not reach the week 168 visit. How missing data were handled is not described.
selection bias: Only patients who completed the randomized phase and chose to continue entered the extension, so the group may be selected.
inappropriate endpoint: Cardiac volumes and MLCL/CL are surrogate measures, and their improvement is described only as trends.
abstract only: Only the PubMed abstract and registry fields were available; full methods and data were not reviewed.

6-minute walk test distance: Serious concern (Structured limitations appraisal)