Huntington's disease: first-ever treatment slows progression by about 75% in UK-led trial

Huntington's disease has been successfully treated for the first time, doctors say, in a UK-led trial that shows a dramatic slowing of the disease three years after a single, complex brain procedure. The study involved 29 patients and was led by Professors Ed Wild and Sarah Tabrizi at University College London, with the treatment combining cutting-edge gene therapy and gene-silencing technologies. The therapy is delivered directly into deep brain structures during 12 to 18 hours of real-time MRI-guided neurosurgery, targeting two regions—the caudate nucleus and the putamen—to curb the production of the mutant huntingtin protein that drives neuron loss in Huntington's disease.

Data released by the company UniQure indicate that, three years after surgery, there was an average 75% slowing of disease progression on a composite measure that includes cognition, motor function, and daily living abilities. Brain biomarkers also suggested that brain cells were better preserved than would be expected as Huntington's disease typically advances. The trial's results are not yet published in full in a peer-reviewed journal, but UniQure described the findings in a statement accompanying the data release. The team emphasized that the results represent a meaningful shift in expectations for Huntington's, a condition that often strikes people in their prime and can be fatal within two decades.

The approach combines a gene-delivery vector with a gene-silencing mechanism. In brief, a safe, engineered virus carries a designed DNA sequence into brain cells, where it is activated to produce a small fragment of genetic material (microRNA) that interferes with the instructions for building the mutant huntingtin protein. By lowering levels of the toxic protein in the brain, the treatment aims to slow or halt neuron death. The surgery requires precise navigation under MRI guidance to place the vector into the targeted brain regions, with the goal of achieving durable, lifelong effects since neurons are not routinely replaced by the body.

While the early data are encouraging, the safety profile remains to be fully characterized in larger, longer-term studies. Some participants experienced inflammation related to the viral vector, causing headaches or confusion, though these symptoms generally resolved or were treated with steroids. Experts caution that the therapy will not be universally available immediately, given the complexity of the procedure and the anticipated cost. Still, researchers say the results mark a turning point, suggesting that gene therapies of this kind could eventually reach more patients if regulatory and manufacturing hurdles are overcome. NHS policy and payer considerations will influence access as the technology advances.

In the United States, UniQure has said it intends to file for regulatory clearance in the first quarter of 2026, with the goal of launching the therapy later that year. Regulatory discussions in the UK and Europe are anticipated to begin in the following year, with the primary focus initially on the United States. Company officials stressed that timelines and pricing are subject to regulatory review and manufacturing capabilities. The lack of a published full data set means independent verification will take place once the results appear in a peer-reviewed forum.

The researchers involved in the UK trial have underscored that this is a foundational moment for Huntington's disease. Professor Sarah Tabrizi, director of the UCL Huntington's Disease Centre, called the results spectacular and said that the magnitude of the effect surpassed what even the most optimistic projections had anticipated. Professor Ed Wild, a neurologist at the National Hospital for Neurology and Neurosurgery, said the data have produced emotional responses among the team and represented a level of progress that could transform the lives of people with Huntington's and their families. He cautioned that more work is needed to confirm durability and to understand which patients are most likely to benefit, but he stressed that the findings are a hopeful signal for durable disease modification.

The disease burden is substantial. Huntington's affects an estimated 75,000 people across the UK, the United States, and parts of Europe, and hundreds of thousands carry the genetic mutation that guarantees they will develop the condition if they live long enough. The new therapy targets a rare, inherited form of the disease and is designed to be effective only in those who carry the huntingtin mutation, a caveat that underscores the need for early and accurate genetic testing and counseling for at-risk individuals.

The treatment protocol involves a one-time surgical intervention, after which the virus remains in the brain as a long-term therapeutic factory producing microRNA that dials down the mutant huntingtin mRNA. By reducing the production of the disease-causing protein, the therapy aims to slow the cascade of neurodegeneration that leads to cognitive decline, motor impairment, and loss of daily living abilities. While the results are promising, experts emphasize that this approach represents a new class of therapy for Huntington's and that broader access will hinge on the outcomes of ongoing and future trials, as well as the ability to integrate surgical delivery into standard care pathways.

The first-hand human dimension of the study is reflected in the experiences of individuals who carry the gene. Jack May-Davis, a 30-year-old medical-court clerk who learned he carries the Huntington's mutation, participated in the UCL trial. He described the breakthrough as absolutely incredible and said it has given him a more hopeful view of the future. He has watched his father, Fred, decline from early changes in behavior and movement in his late 30s to a life requiring near-constant care before he died at 54 in 2016. May-Davis, who is newly engaged, said the possibility of a longer, better quality life feels tangible now, a sentiment echoed by other trial participants who have maintained walking capacities longer than expected and some who have returned to work.

The broader implications of the trial extend beyond treated patients. Tabrizi noted that this development could open doors to similar strategies aimed at delaying or preventing symptom onset, particularly for people who know they carry the Huntington's gene but have not yet developed symptoms, often referred to as stage zero Huntington's. The team is already exploring prevention-focused trials that could intervene before classical symptoms emerge, an approach that could redefine the natural history of the disease for a new generation of at-risk individuals.

A number of questions remain, including how best to identify which patients will benefit most, how to monitor long-term safety, and how to balance cost with potential gains in longevity and quality of life. The research community will also need to examine how such therapies could be integrated with existing symptom-management strategies and supportive care. As the field moves forward, the trial team emphasized gratitude toward the volunteers who made the study possible and urged continued engagement from families affected by Huntington's disease.

As conversations with regulatory bodies in the US, UK, and Europe proceed, researchers say the path from a promising single trial to a widely available therapy will be measured and methodical. The scope of impact will depend on replication of results, the durability of the therapeutic effect, and the ability to scale the complex surgical procedure to broader patient populations. Nevertheless, the current results constitute a landmark in the search for durable disease modification in Huntington's, providing a real sense of possibility after decades of limited treatment options.