An experimental gene therapy has demonstrated significant promise in slowing the progression of Huntington’s disease, a rare form of dementia, by about 75 percent in a late-stage trial. Researchers hailed the breakthrough as a major step forward, though challenges remain in delivery and regulatory approval. Efforts are underway to develop a more practical version of the treatment.
Huntington’s disease arises from a genetic mutation that leads to the buildup of toxic huntingtin protein clumps in the brain, gradually destroying cells and impairing movement, cognition, and mood. Currently, no treatments exist to halt the disease's advancement, with care limited to symptom management.
The therapy in question, AMT-130, developed by biotechnology firm uniQure, delivers genetic instructions to brain cells to produce a molecule that inhibits the creation of these harmful proteins. In a trial conducted by Sarah Tabrizi at University College London, 17 participants received a high dose of the treatment. Three years later, their cognition, movement, and daily functioning were compared to untreated individuals from a database, revealing an average slowdown in disease progression of about 75 percent. Preliminary results were announced in September 2025.
“It is a giant step forward,” Tabrizi said, emphasizing that this marks the first achievement in treating the condition's progression. “It tells you that Huntington’s disease has the potential to be treatable. This gives us a huge window of opportunity.”
Sarah O’Shea at Mount Sinai in New York, who was not involved, described the news as vital amid recent setbacks in Huntington’s research. “We have had so many setbacks in therapies for Huntington’s disease in the last couple of years,” she noted. “So this was huge, not just because it is a breakthrough in terms of slowing disease progress, but also [because] it came at a time where we really needed this hope.”
However, the therapy requires invasive surgery lasting 12 to 18 hours to inject directly into the brain, limiting availability even in advanced medical systems like those in the US and UK. Tabrizi acknowledged potential high costs and accessibility issues if approved.
To address these hurdles, Tabrizi’s team has developed an alternative injected into the spinal fluid surrounding the cord. The phase I study began with the first patient dosed in November 2024, with safety results anticipated around July 2026.
UniQure initially planned to seek US Food and Drug Administration approval in early 2026, but a November 2025 statement indicated uncertainty following FDA concerns over the trial's control group, drawn from an external database rather than a placebo arm. The lack of an internal control complicates assessing placebo effects, though ethical issues prevent such a group due to the procedure's invasiveness.
Matt Kapusta, uniQure’s CEO, affirmed commitment: “We strongly believe that AMT-130 has the potential to bring substantial benefit to patients, and we remain fully committed to working with the FDA to determine the best path forward to rapidly bring AMT-130 to patients and their families in the US.”