8-year-old whose rare condition put him in a wheelchair can walk again — thanks to an experimental drug made just for him

New York Post

10-07-2025

An eight-year-old boy has regained his ability to walk with the aid of a compound found in a common over-the-counter supplement.
The boy's case was detailed in the journal Nature.
The unnamed child was an active athlete until the summer of 2023, when he began to struggle with mobility. Within months, his symptoms progressed to the point that he required a wheelchair.
'Our son's condition dramatically changed in a short period. He went from being the fastest runner in his class and an avid soccer player to struggling just to walk, often limping and experiencing frequent falls,' the boy's parents, who wish to remain anonymous, said to STAT News.
3 Their son was eventually diagnosed with HPDL deficiency, a rare genetic condition that inhibits the body's ability to produce sufficient levels of coenzyme Q10 (CoQ10), a compound critical to cell function.
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Their son was eventually diagnosed with HPDL deficiency, a rare genetic condition that inhibits the body's ability to produce sufficient levels of coenzyme Q10 (CoQ10), a compound critical to cell function.
HPDL deficiency occurs when an individual inherits two mutated versions of the human HPDL gene, which is used in the production of the CoQ10 enzyme.
Without adequate CoQ10, patients struggle with muscle control, walking, and are at a higher risk of seizures.
When HPDL deficiency surfaces later in adolescence, it manifests as muscle weakness and stiffness in otherwise healthy children.
The boy in question was placed on a protocol of CoQ10 supplements — but the pills could only help to a certain extent, as the enzyme is too large to cross the blood-brain barrier.
'[CoQ10] is safe. It's reasonably effective at treating symptoms outside of the brain, but almost completely ineffective at treating symptoms within the brain, because it doesn't get through the blood-brain barrier,' Michael Pacold, an associate professor of radiation oncology at NYU Langone and one of the study authors, told STAT.
But 4-HB is a building block of CoQ10 — and, helpfully, it's thin enough to cross the blood-brain barrier and can be condensed into a powder that is dissolved in a water solution.
3 CoQ10 is available as an over-the-counter supplement to help boost energy and combat fatigue.
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The FDA has not approved CoQ10 or 4-HB as a treatment for any specific disease or condition. However, CoQ10 is available as an over-the-counter supplement to help boost energy and combat fatigue.
While 4-HB is not approved by the FDA, with the consent of the boy's parents and the insistence of his doctors, the FDA approved its use as a single-patient investigational drug — in other words, doctors were permitted to use an unapproved drug for a specific patient to treat a specific condition.
'It was one of the hardest decisions we've ever made [to try the experimental treatment], but doing nothing felt riskier,' said the boy's parents.
'We saw how quickly our son was declining and knew we had to act. After speaking with doctors and doing our research, we got hope and confidence to step into the unknown.'
3 Within a month of receiving treatment, the boy was walking again and even completed a nearly mile-long trek across Central Park.
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A 2021 study tested 4-HB on mice with HPDL deficiency and found that the supplement restored mobility in rodents. Its use in the case of the eight-year-old body is the first time it's been used to treat the condition in humans.
After stopping his CoQ10 supplements, the boy began taking a 4-HB supplement in a 600ml solution. Equivalent to nearly three glasses of water, the liquid cure often caused him to vomit.
This was eventually reduced to a 300ml solution, or just over one glass of water.
However, the upchuck was worth the upturn, as within a month of receiving treatment, the boy was walking again, and even completed a nearly mile-long trek across Central Park.
Researchers are hopeful the success story will serve as a beacon to others. The research team is calling it a medical breakthrough.
'We all dream of this as scientists. And every morning I pinch myself … is this really a dream?' said Pacold.
Now, Pacold and his team are working on a larger study to test the approach on a larger group of children.