First Human Trial for New Huntington's Disease Drug Shows Promise

An experimental injection for treating Huntington’s disease is showing potential in the early stages of clinical development.

Researchers from the University College London reported that IONIS-HTTRx was able to lower levels of the toxic huntingtin protein in the nervous system. This could make it the first drug capable of targeting the underlying cause of this destructive genetic disease.

A total of 46 patients with early Huntington’s disease were enrolled at nine study centers in the United Kingdom, Germany, and Canada.

Investigators administered four doses of either IONIS-HTTRx or placebo through an injection into the spinal fluid so it could reach the brain. Dosages of IONIS-HTTRx were increased several times as the phase I/IIa trial progressed.

The scientists also used an ultra-sensitive assay to measure concentrations of the protein in each patient’s spinal fluid before and after treatment.

Results indicated the drug was able to produce significant, dose-dependent lowering of the mutant huntingtin along with being safe and well-tolerated, according to the announcement.

“The results of this trial are of ground-breaking importance for Huntington’s disease patients and families. 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. The key now is to move quickly to a larger trial to test whether the drug slows disease progression,” said Professor Tabrizi, the Director of the UCL Huntington’s Disease Centre and IONIS-HTTRx Global Chief Investigator, in a statement.

Currently, there are no effective disease-modifying therapies for the condition with the current crop of existing drugs focused only on managing the symptoms of the disease, reported Reuters.

Ionis Pharmaceuticals developed IONIS-HTTRx, which is an antisense oligonucleotide designed to prevent genes from producing certain proteins.

More development is needed to ascertain the drug’s ability to improve clinical outcomes.

The results of this trial prompted Roche to exercise its option to license the product, paying Ionis an estimated $45 million fee. Roche will now be responsible for further development and commercial activities.