Gene therapy for muscular dystrophy could be ready for humans within 2 years

A new gene therapy for Duchenne muscular dystrophy (DMD) shows promise, as it could not only slow the progression of the disease but also potentially reverse muscle damage. Human trials are set 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 such, mobility problems usually begin in patients around the age of three or four, and gradually worsen, with patients no longer able to walk by their teens, and rarely surviving into their twenties.

Because DMD is a genetic disease, it should be a prime target for gene therapy. While scientists have had some success in the past, there is a major problem: the gene that codes for dystrophin is one of the largest genes known. It is therefore much too large to be packaged into the viral vectors that are typically used to insert healthy copies of genes into cells.

Now, scientists at the University of Washington have developed an alternative method, and the idea sounds simple: break up the protein, load the fragments into a series of delivery vectors, and incorporate the instructions to reassemble the protein inside muscle cells.

In tests on mice with muscular dystrophy, they found that dystrophins were once again being produced at high levels and noted that the mice showed ‘significant physiological corrections’. This halted further progression of the disease and even reversed some of the muscle wasting that had already occurred.

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

The researchers say human trials could begin in about two years and the technique could then 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