8-year-old boy walks again after first CoQ10 experimental treatment

An eight-year-old boy diagnosed with a fatal mitochondrial disorder called HPDL deficiency, which disrupts CoQ10 production and causes paralysis, regained his ability to walk following an experimental treatment at NYU Langone Health. The disorder impairs the cell’s energy system by blocking the synthesis of CoQ10, a vital coenzyme for mitochondrial energy production. Building on a 2021 discovery that identified the enzyme HPDL’s role in converting 4-HMA into 4-HB—a key precursor in CoQ10 synthesis—researchers administered 4-HB to the boy under the FDA’s expanded access program. Within two months, he showed significant improvements in balance and endurance, walking over a mile, marking the first real-world reversal of neurological symptoms in HPDL deficiency by supplying CoQ10 precursors rather than CoQ10 itself. This breakthrough originated from earlier mouse model studies demonstrating that supplementing with 4-HMA or 4-HB restored CoQ10 production and countered paralysis.