A new gene therapy allows a drug to reduce the activity of brain cells, reducing seizures.
In a first clinical result using the “chemogenetic” strategy, a team in China treated three patients to control epilepsy.
For the first time, researchers have inserted receptors into the human brain that allow them to manipulate neuronal activity with a drug. The innovative gene therapy was developed to help three people with drug-resistant epilepsy by dampening activity in the areas of the hippocampus responsible for epileptic seizures. The therapy had no significant side effects and appeared to reduce the incidence of seizures, as reported this week by the Chinese team responsible for the clinical trial in The New England Journal of Medicine.
A decade ago, the idea of using this technique — called chemogenetics — on humans was "pure science fiction," says Keri Martinowich, a neuroscientist at the Lieber Institute for Brain Development who was not involved in the study. But while the long-term safety of these therapies still needs to be assessed, she says the technique has "huge potential."
Chemogenetics is widely used by neuroscientists who study brain circuits in animal models. They insert specially designed receptors into a target population of neurons, either by using a virus to deliver the gene for the proteins or by genetically modifying the animal to express the gene. Some of these receptors are designed to activate neuronal activity, while others deactivate it. But this only occurs in the presence of a specific drug.