An experimental drug injected into the spinal fluid of people with Huntington’s chorea lowers the levels of the harmful protein responsible for the development of the disease.
Developed by the Californian biotechnology company Ionis Pharmaceuticals, a drug called Ionis-HTTRx is a synthetic, single-stranded DNA that binds to a defective mutation in the gene responsible for the development of the disease and blocks the production of a harmful protein (huntingtin).
Clinical trials were led by prof. Sarah Tabrizi from University College London Institute of Neurology. 46 people in the early stages of the disease from Great Britain, Germany and Canada participated in them. Four times a month apart, the drug was injected into the fluid surrounding their spinal cord with a long needle – from there it could get into the brain. Each subsequent dose of the drug was higher than the previous one. One-fourth of the patients were a control group and received a placebo, i.e. a drug with no therapeutic effect.
After administration of the drug, the concentration of harmful protein in the cerebrospinal fluid decreased significantly. This change was dose-proportional, suggesting treatment efficacy.
Developing a drug for Huntington’s disease could represent the biggest breakthrough in the treatment of neurodegenerative diseases in 50 years, experts say. It is possible that other neurodegenerative diseases in which abnormal proteins build up can be treated in a similar way.
Only after a longer period of time will it be possible to judge whether the new therapy actually stops the disease or prevents symptoms from occurring. Previous animal studies suggest that this may be the case.
What kind of illness is that?
Huntington’s disease (also called Huntington’s disease) is a neurodegenerative disease that causes neurons in the brain to die. Some patients describe it as a combination of Parkinson’s disease, Alzheimer’s disease, and motor neuron disease. It is manifested by emotional disorders (mood changes, irritability, depression) and impaired memory and physical coordination, usually after the patient reaches 30 years of age. The disease kills slowly – within 10 to 20 years after the first symptoms appear. Its symptoms can be relieved, but its progress has not yet been stopped.
According to statistics, Huntington’s chorea affects 12 people out of 100. and usually runs in families. Half of the children of the patient inherit the mutation, which, however, does not appear until years later.
Chorea is caused by a malfunction of the gene that encodes the huntingtin protein. Normal huntingtin is important for brain development, while pathological huntingtin destroys nerve cells. In order for it to exist, the gene must be read and “translated” into mRNA – the instruction by which a cell makes huntingtin.