CureDuchenne Ventures is happy to announce its latest investment in Myosana Therapeutics, a new biotech company based in Seattle, WA. Myosana is aiming to develop next-generation gene therapy for Duchenne muscular dystrophy and other neuromuscular diseases.
First, let’s set expectations. Myosana’s work is still at very early stages. They are years and many experiments away from clinical trials. But if successful, their approach could dramatically overcome the limitations of current gene therapies in development, and be available to anyone with Duchenne to increase expression of full-length dystrophin in skeletal and cardiac muscle.
One key aspect of Myosana’s approach is that it does not use a virus to get the dystrophin gene inside muscle cells. This breaks free from some limitations that viral delivery presents. Here are some key reasons CureDuchenne is excited about Myosana’s approach:
- Myosana’s approach will work for anyone with DMD, no matter what mutation they have. Since this is gene therapy, the therapy is not restricted to particular types of mutations.
- Myosana’s technology can deliver full-length dystrophin. Dystrophin is the largest gene in the body, and because it does not fit inside of the viruses typically used for gene therapy, a shortened mini-dystrophin currently is used. But these mini-dystrophins (which contain roughly only 1/3 of the dystrophin gene) won’t restore all of the function of the entire full-length dystrophin. For more complete function, the full-length dystrophin is important.
- Since no virus is used, pre-existing immunity to the virus is not a limitation. When exposed to a virus, the body develops antibodies (called neutralizing antibodies) to fight off the virus. Since the viruses currently used for gene therapy are present in the environment, the likelihood that someone has been exposed to it (and has these neutralizing antibodies) increases as they get older. Neutralizing antibodies make viral-delivered gene therapy less effective, and currently individuals with pre-existing antibodies are excluded from most gene therapy trials.
- Redosing will be possible. Viral delivery of gene therapy is currently restricted to a single administration because of the immune response the body mounts against the virus in that first treatment. By not using a virus, Myosana’s technology could be dosed multiple times for maximal effect, or to counter any diminishment of effect over time. This is important because no one knows how long gene therapy will last in a person.
- Myosana’s therapy targets skeletal and cardiac muscle over other tissues in the body. By using antibodies to a specific muscle protein, their therapy binds to the skeletal or heart muscle and delivers the gene inside. Therefore, even though the drug would be given intravenously and circulate throughout the body, it is targeted to get inside the cells that need it most.
CureDuchenne Ventures’s investment in Myosana represents the way we are always looking for innovative strategies to overcome the current limitations in therapy development so that we can help every individual with Duchenne muscular dystrophy have access to transformative treatments.