Breakthrough gene therapy shows promise in Duchenne muscular dystrophy

The treatment took place in golden retrievers, that are commonly afflicted by DMD, and involved injecting microdystrophin (a shortened version of the dystrophin gene) to restore muscle strength. The therapy was found to be effective, with dogs that had been treated showing stabilisation of symptoms two years after. In the usual course of the disease, without treatment, the dogs would not have been expected to live more than six months.

DMD is a heritable condition that affects one in 5,000 boys, with most not making it beyond their thirtieth year. The condition is related to the body’s ability to produce dystrophin, a protein essential for muscle function, and is caused by abnormalities in the DMD gene. The research delivered a virus into the body of the animals, which introduced the microdytrophin gene through the body.

After the one time injection, the scientists found that levels of dystrophin in the body of the dogs reached a much higher level than previously. Additionally, further promising aspects of the results were that the dogs did not need immunosuppressive treatment and no safety issues were raised.

"This preclinical study demonstrates the safety and efficacy of microdystrophin, and makes it possible to consider developing a clinical trial in patients. Indeed, this is the first time that it has been possible to treat the whole body of a large-sized animal with this protein. Moreover, this innovative approach allows treatment of all patients with Duchenne muscular dystrophy, regardless of the genetic mutation responsible," says Caroline Le Guiner, the main author of the study and Senior Scientist at the University of Nantes.

It is hoped that the next step will be to take the gene therapy into clinical trials to determine whether the treatment may be efficacious in boys. Due to the complexity and size of the dogs involved, it is expected that the research holds a great degree of promise.