Peptide Library

Human study PLS-00118

Initial Psychometric Evaluation of the Barth Syndrome Symptom Assessment (BTHS-SA) for Adolescents and Adults in a Phase 2 Clinical Study.

Randomized controlled trial · 12 participants enrolled

Version 1 · published November 7, 2026 · evidence through November 7, 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.

  • Initial Psychometric Evaluation of the Barth Syndrome Symptom Assessment (BTHS-SA) for Adolescents and Adults in a Phase 2 Clinical Study.primary · Orphanet journal of rare diseases · 2025-04-25 · PMID 40281531 · DOI

Design and participants

Design
Randomized controlled trial
Population
Adolescent and adult white males with genetically confirmed Barth syndrome (TAZ mutations). Mean age 19.5 years (SD 7.7). Overall symptoms were rated mild to very severe.
Conditions
Barth syndrome
Setting
Phase 2 clinical trial (TAZPOWER); sites not stated
Planned enrollment (registry)
Not reported
Enrolled
12
Randomized
Not reported
Completed follow-up
Not reported
Funding
PubMed lists non-U.S. government research support; funder not named
Authors’ conflicts
Not stated

Intervention and comparator

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

  • Elamipretide (intervention) · elamipretide · Elamipretide, daily subcutaneous injections (crossover period) · subcutaneous · not stated · Not reported assigned
  • Placebo (comparator) · Placebo (crossover period) · placebo · subcutaneous · not stated · Not reported assigned

What the authors reported

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

BTHS-SA overall symptom severity rating

unclear outcome · patient-important · not stated · Patient-reported overall symptom severity

  • —: proportion 41.7 — Overall symptoms rated mild in 5 participants (41.7%) and moderate in 5 (41.7%), pooled across all participants
  • —: proportion 8.3 — Overall symptoms rated severe in 1 participant (8.3%) and very severe in 1 (8.3%)

BTHS-SA fatigue and myopathy scores: internal consistency

unclear outcome · patient-important · not stated · Cronbach alpha for the 3-item fatigue score (3 FS), 4-item fatigue score (4 FS) and 5-item myopathy score (5MS)

  • —: other 0.67 — Alpha 0.67 for the 3 FS, 0.72 for the 4 FS and 0.66 for the 5MS

BTHS-SA test-retest reliability

unclear outcome · patient-important · two test-retest intervals · Intraclass correlation across two test-retest intervals

  • —: narrative — ICC values ranged from 0.79 to 0.94 across the two test-retest intervals

BTHS-SA convergent validity and responsiveness

unclear outcome · patient-important · not stated · Correlations of BTHS-SA scores with PROMIS Fatigue SF and a patient global rating, and of BTHS-SA change scores with a global impression of change

  • —: narrative — Correlations with PROMIS Fatigue SF were r 0.59, 0.76, 0.68 and 0.61 for the 2 FS, 3 FS, 4 FS and 5MS respectively
  • —: narrative — Change scores correlated with a global impression of change at r 0.81, 0.79, 0.82 and 0.80 for the 2 FS, 3 FS, 4 FS and 5MS respectively

Adverse events

None reported. That is not evidence of safety.

Monitoring: Not reported in this record

The authors concluded (paraphrased): The sample is small, but the authors conclude the BTHS-SA appears to give reliable scores supporting valid inferences. They suggest it may be useful for evaluating treatment benefit in Barth syndrome.

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

  • small or imprecise: Only 12 participants were analysed, which the authors acknowledge limits strong conclusions.
  • inappropriate endpoint: The analysis reports psychometric properties of a questionnaire. It gives no elamipretide versus placebo treatment effect.
  • abstract only: Only the abstract is available. Randomization, dosing, follow-up and safety details are missing.
  • selective reporting: Efficacy and safety results of the parent TAZPOWER crossover trial are not reported in this record.

No risk-of-bias assessment has been published for this study’s results.

Claims this study informs

Where each value comes from

  • arms: PMID 40281531, abstract (Methods, sentence 1) · extracted by AI (automated, not verified by a person) · abstract only
  • author_conclusion: PMID 40281531, abstract (Conclusion, sentences 1-2) · extracted by AI (automated, not verified by a person) · abstract only
  • design: PMID 40281531, abstract (Methods, sentence 1) · extracted by AI (automated, not verified by a person) · abstract only
  • limitations: PMID 40281531, abstract (Conclusion, sentence 1) · extracted by AI (automated, not verified by a person) · abstract only
  • outcomes: PMID 40281531, abstract (Methods, sentence 2) · extracted by AI (automated, not verified by a person) · abstract only
  • participants: PMID 40281531, abstract (Results, sentence 1) · extracted by AI (automated, not verified by a person) · abstract only
  • population: PMID 40281531, abstract (Results, sentence 1) · extracted by AI (automated, not verified by a person) · abstract only
  • results: PMID 40281531, abstract (Results, sentences 1-5) · extracted by AI (automated, not verified by a person) · abstract only

  • Version 1 · published November 7, 2026 · evidence through November 7, 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.

These assessments describe published research. Records marked automated were produced by AI under the published methodology and have not been reviewed by a person; they can contain errors. None of this is medical advice, not a statement about any product’s safety for human use, and not a regulatory approval. Peptide Library’s vendor and partner relationships play no part in them (editorial independence).