This week has been an exciting week in the drug industry with it being revealed that a new drug to treat Huntington’s disease is being trialled in humans after success in both mice and monkeys.
The new drug, called IONIS-HTTRx, silences the gene known to be responsible for the production of a protein causing Huntington’s disease and is believed to be able to reverse the symptoms.
What is Huntington’s Disease?
Huntington’s disease is a neurodegenerative condition which damages nerve cells in the brain. This brain damage gets progressively worse over time and can affect movement, cognition (perception, awareness, thinking, judgement) and behaviour.
What is the cause of Huntington’s disease?
The condition all stems from a faulty gene. The normal copy of the gene produces a protein called huntingtin, but the faulty gene contains an abnormal region of what are called CAG repeats. This area is larger than normal and produces a mutant form of huntingtin.
What is the probability of inheriting it from a parent?
50:50. A parent with the Huntington’s disease gene has one good copy of the gene and one faulty copy. Their child will inherit one of these genes. However it cannot be determined when the condition will develop in a child, it may not be until their adulthood until the symptoms progress.
How many people in the UK are affected by the condition?
12 people per 100,000 are affected by the condition.
The latest in the drug development..
When they tested IONIS-HTTRx on mice with the disease their motor function improved within a month and within two months their health was restored to normal. In monkeys the drug was found to decrease the HTT protein throughout the central nervous system by 50 per cent. The drug is delivered into the cerebral spinal fluid via lumbar injection, as antisense drugs do not cross the blood brain barrier – a protective sheath that prevents toxins entering the brain. The drug is now being trialled in humans in low doses (participants are given four spinal injections each separated by a month) to check that it is safe for larger trials into its efficacy to begin.
“It is very exciting to have the possibility of a treatment that could alter the course of this devastating disease,” said clinical study principal investigator Dr Blair Leavitt, of the University of British Columbia in Vancouver.
Some positive news in the world of drug trials…a story to watch!