How big could a potential new drug for Huntington's disease be? The BBC puts it this way: "Experts say it could be the biggest breakthrough in neurodegenerative diseases for 50 years." The news is preliminary—full trial results should be published in 2018—but early indications are good. As the Guardian explains, the only currently available treatments address solely symptoms, allowing the disease to march on to its deadly conclusion, which can occur within a decade of diagnosis. But this drug, called Ionis-HTTRx, appears to have slowed the progression. CNN reports Huntington's is caused by a single gene defect that causes cells to produce a toxic form of the huntingtin protein, which kills nerve cells in the brain. "You end up in almost a vegetative state," says a trial participant. Ionis-HTTRx prevents the toxic protein from being made.
Some 46 patients in the early stages of the disease participated in the UK trial and received four spinal injections—either the drug or a placebo—a month apart. Trial leader Sarah Tabrizi calls it "probably the most significant moment in the history of Huntington’s since the gene [was isolated]. ... For the first time a drug has lowered the level of the toxic disease-causing protein in the nervous system, and the drug was safe and well-tolerated." But the trial needs to be bigger and longer, and that's what is happening next. If the findings are confirmed, Tabrizi envisions a future where those with the gene take the drug in a preventative manner. But the implications could be even bigger: "The drug's like Lego," says a neurologist involved in the trial. "You can target [any protein]," meaning applications for diseases like Alzheimer's may be possible.