Gene therapy for muscular dystrophy could be available in humans within 2 years

A new gene therapy for Duchenne muscular dystrophy (DMD) has shown promise not only in slowing the progression of the disease but also potentially reversing muscle damage. Human trials are expected to begin within two years.

DMD is a debilitating genetic disease that disrupts the production of dystrophin, a protein that maintains muscle strength and integrity. As a result, mobility problems typically appear in patients around the age of three or four and gradually progress, so that patients are unable to walk by adolescence and rarely survive beyond the age of 20.

Being a genetic disease, DMD should be a prime target for gene therapy, and while scientists have had some success in the past, there is a major hurdle: the gene that codes for dystrophin is one of the largest known, making it far too big to fit into the viral vectors that are usually used to insert healthy copies of genes into cells.

Now, scientists at the University of Washington have developed an alternative method, and the idea seems simple: break down that protein, load the fragments into a series of delivery vectors, and integrate the instructions to reassemble the protein in muscle cells.

In tests on mice with muscular dystrophy, they detected new production of dystrophins in large quantities and noted that the mice showed “significant physiological corrections.” This halted the progression of the disease and even reversed some of the muscle loss that had already occurred.

Other studies have gotten around the problem by creating smaller versions of dystrophins, with promising effects when tested in dogs. However, the team in the new study says their method produces better results. As a bonus, the new technique can work with a lower dose than other gene therapies, resulting in fewer side effects such as potentially damaging immune responses that can occur.

Researchers say human trials are expected to begin in about two years and the technique could be applied to other genetic diseases caused by mutations in large genes.

The research was published in the journal Nature.

Source: University of Washington via Science Daily