In the basement of a pediatric intensive care unit, a quiet kind of medical revolution unfolded.
Jaylen Karle entered the world not through a planned surgery or under calm circumstances, but via a natural delivery, his mother, Jordan Karle, holding fast to hope even as doctors braced for the worst. Diagnosed in utero with Barth syndrome—a deadly, ultra-rare genetic disorder affecting fewer than 200 known individuals in the U.S.—Jaylen was born with a failing heart and long odds. His tiny left ventricle barely moved blood, with an ejection fraction of just 20%. For weeks, clinicians stabilized him with ventilators, inotropes, and unrelenting care.
And then, on day 34 of life, doctors made a bold move.
With no approved treatments for Barth syndrome and standard therapies proving inadequate, they turned to an investigational drug: elamipretide. Developed by Stealth BioTherapeutics, the therapy targets the mitochondria—the cellular “powerhouses” disrupted in Barth syndrome. Through the FDA’s expanded-access pathway, clinicians gained emergency approval to administer the drug. Jaylen received a daily subcutaneous dose.
What followed bordered on the miraculous. By discharge, Jaylen’s ejection fraction had risen to 60%. His once-struggling heart was pumping normally.
This peer-reviewed case, published in the European Heart Journal – Case Reports (PubMed), marks the first documented use of elamipretide in a newborn with Barth syndrome. It’s a milestone for medicine—and a lifeline for a family from Omaha, Nebraska, who had no other options.
When Time Is the Enemy
Barth syndrome isn’t just rare—it’s ultra-rare. Caused by mutations in the TAZ gene, it leads to dangerously low levels of a lipid called cardiolipin, essential for mitochondrial function. The consequences are devastating: heart failure, muscle weakness, life-threatening infections. Most patients are boys. Most die young.
In this context, the newborn’s story highlights the painful calculus faced by clinicians and families navigating rare diseases. Wait for more data—or act with what’s available? There are no easy answers. The team behind this case had an investigational therapy, desperate need, and a narrow window to act. So they did.
The success offers a powerful glimpse of what’s possible when translational science meets clinical courage. It also raises pressing questions: How do we build faster, more flexible pathways for promising therapies in ultra-rare conditions? Can regulators and drugmakers meet families where they are—at the bedside, not just in the trial protocol?
A Call to Act—Not Just Observe
The science is promising. The need is urgent. And yet, the FDA recently announced it would not meet its expected April 29 decision date on elamipretide, delaying a long-awaited ruling on the therapy’s approval.
In response, the Barth Syndrome Foundation has issued a clear appeal: complete the review as quickly as possible, provide a clear and definitive new decision date, and approve elamipretide for all Barth patients—regardless of age.
The FDA has an opportunity not just to follow the data, but to lead with compassion. For the children fighting this disease, and for the families who’ve waited far too long, the clock is still ticking.
You can join this call by urging the FDA to act swiftly and decisively—and by standing with the Barth syndrome community as it fights for the first-ever approved treatment.
To help families like Jaylen’s, visit www.barthsyndrome.org or view the foundation’s full statement: Barth Syndrome Foundation Calls for Urgent FDA Action
