Gene Therapy Breakthrough Slows Huntington’s Disease Progression by 75%

Gene Therapy Offers New Hope for Huntington’s Disease

For decades, Huntington’s disease has been a relentless diagnosis—a rare, inherited disorder that chips away at mind, movement, and identity. Until now, all medical science could offer was symptom management, not a way to slow the disease itself. But recent results from a trio of clinical trials have changed the landscape, unveiling a gene therapy that could fundamentally alter the future for patients and families.

Understanding Huntington’s: The Genetic Domino Effect

Huntington’s disease strikes when a single gene—HTT—mutates, causing toxic proteins to accumulate in the brain. The gene’s flaw is a repetitive sequence, where a trio of DNA letters (CAG) is repeated far beyond normal limits. While most people have 10 to 35 repeats, those with Huntington’s have 36 or more, sometimes exceeding 120. This genetic stutter forces cells to produce a malformed huntingtin protein, which then fragments and disrupts the neurons responsible for movement, cognition, and mood.

The result? A slow but devastating loss of control—over body, mind, and, ultimately, independence. Symptoms typically appear in one’s 30s or 40s and can last for decades. For the roughly 8,000 people living with the disease in the UK, and an estimated 1 in every 10,000 to 20,000 in the U.S., the outlook has been grim: no cure, no way to slow the underlying damage.

AMT-130: Science Steps Ahead of the Disease

Enter AMT-130, a gene therapy developed by uniQure and tested in collaboration with University College London (UCL). Unlike traditional treatments, which target the symptoms—depression, erratic movements, hallucinations—AMT-130 aims at the heart of the problem: the HTT gene itself.

This therapy uses a harmless virus as a delivery system, ferrying a specially designed microRNA into the brain’s most vulnerable regions, the putamen and caudate nucleus. The microRNA acts like a genetic dimmer switch, latching onto the mutant gene’s messenger RNA and reducing the production of both healthy and defective huntingtin proteins. The process is not absolute; it doesn’t erase the gene, but it turns down the volume enough to slow the toxic cascade.

Administering AMT-130 is no trivial feat. It requires a single, highly precise brain surgery, guided by MRI, during which doctors insert catheters deep into targeted brain areas. But that one dose, researchers believe, may last a lifetime.

Clinical Triumph: Numbers That Tell Human Stories

The results, announced in September 2025, were nothing short of historic. In a trial involving 29 patients, those who received the highest dose of AMT-130 experienced a 75% reduction in disease progression over three years, compared to patients who received standard care, according to Live Science and Sky News. These figures are more than statistics—they represent years of functional life regained, milestones once thought unreachable.

Dr. Sarah Tabrizi, scientific advisor for the trial and director of the UCL Huntington’s Disease Centre, called the data “the most convincing evidence in the field to date.” She explained, “For patients, AMT-130 has the potential to preserve daily function, keep them in work longer, and meaningfully slow disease progression.”

One patient, Jack May-Davis, expressed awe at the impact: “This feels like a huge moment that will mean so much to families who carry the Huntington’s gene.” For Dr. Ed Wild, lead investigator at UCL, the transformation was visible: “My patients in the trial are stable over time in a way I’m not used to seeing in Huntington’s disease. One of them, my only medically retired Huntington’s disease patient, has been able to go back to work.”

Beyond day-to-day function, the therapy showed biological benefits. Patients receiving high-dose AMT-130 had declining levels of neurofilament light protein (NfL)—a marker of neuronal injury—while untreated patients typically see this marker spike over time. Side effects were mainly tied to the surgery itself and resolved without lasting harm.

From Breakthrough to Broader Impact

Researchers and advocacy groups alike have hailed the findings as a seismic shift. Professor Mike Hanna of UCL described it as a “new chapter in gene therapy development for Huntington’s disease” with implications for other neurodegenerative conditions. Cath Staney, CEO of the Huntington’s Disease Association, called the trial “a significant breakthrough” that would bring hope to many.

What’s next? The manufacturer, uniQure, plans to submit applications to the U.S. Food and Drug Administration (FDA) and European regulators for accelerated approval. The therapy already holds Breakthrough Therapy and Regenerative Medicine Advanced Therapy designations from the FDA, signaling its high potential for patients with unmet needs.

Researchers hope future trials will include patients at even earlier stages—perhaps even before symptoms appear. Professor Tabrizi envisions a future where gene therapy could prevent the onset of symptoms altogether, a radical shift from today’s paradigm of managing decline.

Personal Courage, Collective Progress

Behind every data point is a human story of courage. Patients volunteered for major neurosurgery, not just for personal hope but for the benefit of those who will come after them. As Dr. Wild reflected, “Trial results come through in numbers and graphs, but behind each datapoint is an incredible patient who volunteered to undergo major neurosurgery to be treated with the first gene therapy we’ve ever tested in Huntington’s disease. That is an extraordinary act of bravery for the benefit of humanity.”

While hurdles remain—cost, access, and the need for ongoing research—the results of the AMT-130 trials have redefined what is possible for Huntington’s disease. For the first time, families affected by this devastating genetic legacy can look to the future with cautious optimism.

Assessment: The clinical success of AMT-130 marks a pivotal moment in the fight against neurodegenerative diseases. By targeting the root genetic cause, this therapy not only slows the progression of Huntington’s but also opens new avenues for tackling similar disorders. The bravery of trial participants and the persistence of researchers have turned a distant hope into a tangible reality, rewriting the story of Huntington’s disease from inevitability to possibility.