Huntington’s disease breakthrough: what to know about the gene therapy

Experimental gene therapy has become the first treatment to successfully slow down the progression of Huntington’s disease. Although the results are always preliminary, the approach could be a major breakthrough and can even lead to new therapies for other neurodegenerative conditions, such as Parkinson and Alzheimer.

How does therapy work?

Treatment, called AMT -130, target abnormal proteins in the brain that are responsible for the progression of Huntington’s disease. People with the disease have a genetic mutation that makes Huntingtine protein normally-so-to accumulate in toxic tufts inside brain cells, ultimately killing them. Over time, this leads to memory loss, walking difficulties, linked speeches and other symptoms.

Experimental therapy, developed by the Dutch company of Unique biotechnology, stops the production of these mutant proteins. He does so by delivering genetic material to brain cells wrapped inside a harmless virus. This material then orders the cells to produce a small genetic molecule, called microarn, which is designed to intercept and deactivate the instructions to produce toxic protein. Think about it as a molecular stop signal.

How and where is the treatment delivered?

Treatment targets two regions of the brain impacted for the first time by Huntington’s disease: caudé nucleus and putamen. The two are located deep inside the brain, so doctors use brain scanners in real time to guide a thin catheter. The entire procedure takes 12 to 6 p.m. An injection seems to be sufficient to definitively reduce the levels of mutant Huntingtine in the brain.

What is the effectiveness of gene therapy?

The preliminary results published by Unique suggest that gene therapy slows down the increase in Huntington’s disease by around 75%.

The conclusion comes from a clinical trial led by Sarah Tabrizi to the University College in London and its colleagues, in which 17 people with Huntington have received a high dose of treatment. Three years later, the researchers compared decreases in cognition, movement and daily operation with those of similar and not treated individuals. Lower reductions which would normally be observed in a year of progression of the disease occurred in patients treated for four years on average, said Tabrizi BBC News. Those who have received treatment have also seen lower levels of a protein indicating brain lesions in their cerebrospinal fluid, also indicating gene therapy slows Huntington’s progression.

“These results reinforce our conviction that the AMT -130 has the potential to fundamentally transform the landscape of treatment for Huntington’s disease,” Walid Abid-Saab said in a press release.

Are there side effects?

Although Unique has not published complete data on the side effects of therapy, he has said that so far the drug seems to be safe and well tolerated. The most common side effects were headache and confusion, which resolved without treatment or with steroids to reduce inflammation.

When will therapy be available?

In a press release, UNIQUERE said that he planned to submit a request to the Food and Drug Administration of the United States early next year and, pending approval, the product could be launched before 2027.

“However, it is still early and many more tests are necessary to see if there are side effects of this new gene therapy, how long the advantages last and how long it works,” Zofia Miedzybrodzka told Aberdeen University in the United Kingdom in a press release.

Could this approach help deal with other brain conditions?

If this gene therapy is ultimately successful, it could lead to the development of similar therapies for other neurodegenerative conditions, such as Parkinson’s disease or other types of dementia, David Rubinsztein said at Cambridge University in a statement. Researchers should simply change genetic material so that it targets toxic proteins that stimulate these conditions. “It could be a major breakthrough,” he said.