Elamipretide in pediatric Barth syndrome: from heart failure to school return

In a 5-year-old with Barth syndrome and severe heart failure, six months of elamipretide treatment was associated with marked improvement in cardiac function, nutritional status, and quality of life, allowing the child to return to full-time school and be temporarily removed from the transplant list.

Journal article — single-patient compassionate use case report. Population: preschool-aged child with genetically confirmed Barth syndrome and advanced heart failure in France. Sample size: 1 child. Follow-up: 6 months. Interventions: elamipretide 10 mg/day subcutaneously.

At treatment initiation, LVEF was 20% with moderate-to-severe mitral regurgitation and the child was dependent on gastrostomy feeding. Over six months, LVEF improved to 50%, mitral regurgitation decreased to mild, and Ross class improved from IV to I. Substantial gains were observed in functional capacity, nutritional status, and health-related quality of life. The patient returned to full-time school and remained temporarily suspended from the transplant list. Treatment was generally well tolerated, with one transient non-serious episode of abdominal pain and moderate pancreatic enzyme elevation that resolved without discontinuation.

This paper provides the first reported experience with elamipretide (SS-31) in a non-US, preschool-aged pediatric Barth syndrome patient, extending the age range previously reported. It documents improvements in cardiac, functional, nutritional, and quality-of-life outcomes over six months in a single severely affected child, but does not establish efficacy or safety, and no controlled or long-term data are provided.

Key findings

• Left ventricular ejection fraction improved from 20% to 50% over six months.
• Mitral regurgitation decreased from moderate-to-severe to mild.
• Ross class improved from IV to I.
• The patient returned to full-time school and remained temporarily suspended from the transplant list.
• One transient, non-serious episode of abdominal pain with moderate pancreatic enzyme elevation occurred and resolved without treatment discontinuation.

Limitations

• Single case report with no control group.
• Short follow-up of six months.
• Compassionate use setting with open-label, non-randomized treatment.
• Authors note broader pediatric evaluation is warranted.

The record

• Journal: Orphanet journal of rare diseases
• Published: 2026-07-07
• PMID: 42415111 — DOI: 10.1186/s13023-026-04487-z
• Author countries: France, USA

Peptide profiles: SS-31.

All indexed evidence: SS-31 trials & papers.

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