The FDA is failing rare disease patients. I’m one of them.

I’ve been on elamipretide for three years now. It is the only treatment that has made a meaningful difference in my life with primary mitochondrial myopathy—a degenerative genetic condition that impairs how my cells convert food and oxygen into energy. Mitochondria provide over 90 percent of the energy our bodies need; when they fail, the highest-demand tissues—like muscle, brain, and heart—are hit the hardest. For me, that has meant profound fatigue, muscle weakness, shortness of breath, double vision, and severely reduced stamina. There is no approved disease-modifying treatment—only supportive care. The disease is terminal, and until now, no therapy has reached this point in offering real potential to change its course.

Before illness forced me to step back, I was a medical oncologist and physician scientist. For over 20 years, I worked at a large academic medical center in the Eastern United States, where I helped advance cancer care and led a Cancer Survivorship Program. Now I find myself on the other side of the system I once served.

For the last three years, I have received a drug called elamipretide through an expanded access program (the U.S. Food and Drug Administration, or FDA, defines “expanded access” as “a potential pathway for a patient with a serious or immediately life-threatening disease or condition to gain access to an investigational medical product for treatment outside of clinical trials when no comparable or satisfactory alternative therapy options are available”). Although I continue to rely on a power wheelchair and ventilator, elamipretide has helped me regain abilities I had lost—like dressing and bathing—and maintain a greater level of independence at home. By stabilizing bodily systems that were otherwise in decline, it has allowed me to contribute more meaningfully to daily life, enabling my family to continue their work and routines, and reducing the need for more intensive and costly care—easing strain on both our household and the broader health system.

Elamipretide is the first medication to reach this stage of review for primary mitochondrial diseases. To date, elamipretide has been used in clinical trials and expanded access programs around the world—encompassing over hundreds of accumulated patient‑years of exposure—providing meaningful real‑world safety and efficacy data. And now, without explanation, the FDA is at risk of ending it all.

This isn’t about grudges: It’s about the highly complex FDA regulatory cycle we’re stuck in around the development of elamipretide for Barth syndrome, a related ultra-rare condition that also falls under the category of primary mitochondrial disease. Here is a brief overview: the first New Drug Application (NDA), filed in 2019, was rejected for not meeting endpoints. For both that and the subsequent NDAs, the FDA provided guidance on endpoint selection, but there were differences in perspective between the agency and the sponsor regarding how best to measure meaningful treatment benefit in such a rare and variable disease. The second NDA was submitted in January 2024 and placed by the FDA into the standard (full) approval pathway, with priority review designation. After demonstrating meaningful clinical benefit with minimal toxicity and earning a favorable advisory vote in November 2024, the FDA denied the application in June 2025—recommending instead that the company submit a third NDA but this time under the accelerated approval pathway. The Stealth company that manufactures elamipretide is seeking reconsideration from the FDA, and the FDA’s final decision is expected in early August of 2025.

Why is this relevant?

Without timely approval, the expanded access framework—including treatment for people like me—is at risk of being discontinued. Although clinical trials are ongoing for primary mitochondrial myopathy, elamipretide cannot remain in production without an approved indication generating income from insurers. If Barth syndrome is not approved, the manufacturer will be forced to stop production—likely within months—including for those of us currently receiving it through expanded access (Stealth has already implemented a 30 percent personnel reduction). That’s not a dramatic threat—it’s just business reality.

Any approval—accelerated or full—would allow elamipretide to remain in production. But only full approval ensures the drug can be accessed reliably, reimbursed by insurers, and protected from the kind of regulatory uncertainty that surrounds accelerated approval. It would also allow for critical next steps, like dose refinement and stratification by disease progression—innovations impossible without a foundation of approval.

Some have argued that the FDA can’t approve a therapy simply because patients are suffering—that it must adhere strictly to conventional evidence standards. But no one is asking the FDA to abandon rigor. Elamipretide for Barth syndrome has met the FDA-defined endpoints and earned a favorable advisory vote. Furthermore, it also holds FDA orphan drug designation, formally recognizing the condition as rare, serious, and lacking adequate treatments. The Orphan Drug Act was established decades ago to facilitate approval of therapies for diseases too rare to meet traditional trial size or endpoint expectations. The FDA’s own Rare Disease Guidance affirms that it may accept greater uncertainty and encourages the use of natural history, real-world data, and innovative trial designs—precisely the flexibility warranted here.

What’s worse is that this isn’t just about one drug. If the FDA walks away from elamipretide, it will send a chilling message to researchers and developers: investing in rare diseases is too risky. Why take a chance on a therapy that may never be approved—even when it proves safe and helpful?

Rare disease doesn’t discriminate. It could touch any family, any child, at any time. And when it does, families deserve to know that our regulatory system won’t abandon them. The science is here. The safety is proven. The need is undeniable.

We are asking the U.S. Food and Drug Administration to reconsider its denial of elamipretide and grant full, traditional approval—the first ever for primary mitochondrial disease. Doing so would honor the advisory committee’s recommendation, uphold the standard NDA pathway the FDA itself selected, and fulfill the intent of the Orphan Drug Act. We also urge the FDA to approve the drug with broad labeling, so that all appropriate patients—not just a narrow trial subset—can access a therapy that has demonstrated meaningful benefit. No more delays. No more deferrals. No more circular barriers. This is not just about one drug—it’s about whether we are willing to meaningfully advance treatment for (ultra) rare diseases at all.

G. van Londen is a medical oncologist, geriatrician, and physician scientist.