After more than a decade of development, families say time is running out for children with Barth syndrome as the experimental therapy elamipretide faces yet another regulatory delay. Reported by NBCNews.com, seven-month-old Gilbert Dryden, diagnosed shortly after his birth on Dec. 24, 2024, has only weeks of medication left, according to his family. The ultra-rare genetic disorder, which impairs mitochondrial function, can trigger heart failure, profound muscle weakness, and dramatically shortened life spans. The Barth Syndrome Foundation reported two infant deaths in the past week; only about 150 people in the U.S. live with the condition.
Elamipretide, developed by Stealth BioTherapeutics, is a daily injection designed to support damaged mitochondria. Small studies suggest it is safe and beneficial, and the company reports trial participants showed about 45% gains in muscle strength and 40% improvement in heart function, with most remaining on therapy for more than eight years. Families like the Drydens credit the drug with stabilizing their children when standard heart medications such as beta blockers and ACE inhibitors are not enough. Even heart transplantation, sometimes necessary, cannot resolve ongoing muscular and skeletal complications.
Despite an October 2024 advisory committee vote of 10–6 recommending approval—the first step toward a therapy for Barth syndrome—the Food and Drug Administration declined to approve elamipretide in late May without publicly stating its reasons. Earlier, an FDA inspection identified manufacturing issues at a Stealth facility that the company says it has resolved. In August, following a meeting with the agency, Stealth was told to resubmit a new drug application for a third time. The company says no additional clinical or safety data were requested, but manufacturing-related steps could push review timelines by at least six months. Financial strain now threatens the program.
On Monday, Stealth submitted the new application, seeking accelerated approval on a faster timetable than initially suggested by regulators. Accelerated approval could acknowledge the severe, unmet need and the practical limits of generating large, definitive trials in an ultra-small patient population.
Clinicians warn that without access to elamipretide, children with Barth syndrome face heightened risks of heart failure recurrence, repeat hospitalizations, and deterioration that may require prolonged inpatient care until transplant. Advocacy groups and some members of Congress are pressing for clarity and speed, arguing that regulatory hesitancy is out of step with the urgent medical need. Observers also point to leadership turnover at the FDA and a broader slowdown in drug approvals this year as factors complicating rare-disease decisions.
For families, the stakes are immediate and personal. Each remaining vial in the refrigerator represents borrowed time while they wait for a verdict that could determine whether their children continue receiving a therapy they believe is keeping them alive.
