Optogenetic techniques, which have proved successful in laboratory tests for around ten years already, could soon be used to treat human patients.

Optics and genetics combine to combat chronic pain

Optogenetics is a biological field which involves using light to control cells in living tissue, typically neurons. The scientific principle is that light can be used to activate or inhibit neurons in order to stimulate the activity of certain cells while leaving others untouched. Optogenetics has enabled major discoveries to be made regarding brain function and such pathologies as depression and obsessive-compulsive disorder (OCD). The techniques have been tested on animals for around ten years and could soon be used to treat chronic pain and some types of degenerative illnesses in humans.  

Californian startup Circuit Therapeutics has been working to perfect a method intended to enable the use of optogenetics on human patients. Up to now the treatment has required a serious surgical operation, implanting optic fibre into the brain in order to create a light source. However Circuit Therapeutics has developed a miniature patch designed to do the same job, thus avoiding the need for major surgery. The team has also developed a new method whereby a virus is injected to activate the right neurons, a technique which has been shown to work well on animals in the laboratory.

Circuit Therapeutics has just signed a contract with the Defense Advanced Research Projects Agency (DARPA), an agency under the United States Department of Defense, with the aim of developing a therapy to treat chronic pain experienced by military personnel. If the results prove conclusive, research into optogenetics could in the longer term be used to treat conditions such as depression, behavioural disorders and Parkinson’s disease.

By Guillaume Renouard