“We are extremely pleased to receive this funding from Cure Duchenne Ventures. This is an important milestone for Myosana and will help accelerate our novel platform technology for non-viral, full length dystrophin gene delivery,” Steve Runnels, the company’s CEO, said in a press release.
This follows another recent investment by CureDuchenne, helping work by Dyne Therapeutics that targets the genetic makeup of DMD to promote, in a more precise way, production of a shorter version of the dystrophin protein in muscle cells. The amount given to Dyne was not disclosed.
Duchenne is caused by mutations in the DMD gene. This gene codes for dystrophin, a protein mostly found in skeletal muscles (used for movement) and in the cardiac muscle. Dystrophin is needed to protect muscles from damage as they contract and relax.
Current therapies for Duchenne patients involve exon skipping approaches that allow muscle cells to produce a shorter version of the dystrophin protein. Gene therapies using a modified adeno-associated virus (AAV) to deliver a copy of the DMD gene to muscle cells are also being studied.
But like in exon skipping, this approach is intended to help muscle cells produce a protein that is functionally similar to dystrophin but smaller in size, which might provide only partial improvement of muscle function.
This is because AAV vectors have a small capacity, and are only able to carry about one third of the DMD gene, the largest known human gene. AAVs have other problems as well, including their cost and the potential to induce unwanted immune responses to their viral shell, which could prevent redosing. These vectors are also not directed to muscle cells, requiring high doses.
Myosana is developing a gene therapy platform expected to overcome these limitations. The company’s approach is designed to deliver the full DMD gene to skeletal and cardiac muscle cells without needing viruses, potentially enabling patients to receive repeat dosing with fewer immune side effects.
The technology uses three components that, the company reports, help to ensure proper gene delivery. One component condenses the DNA of the DMD gene and protects it from degradation, while another provides stability and helps the gene exit blood vessels and enter the muscle. The final component binds to a specific protein on muscle cells to ensure that the DNA is delivered directly to these cells.
“Our muscle targeted, non-viral gene delivery platform overcomes many of the limitations of AAV viral vectors which deliver ‘micro-dystrophin genes,’” said Nick Whitehead, chief scientific officer of Myosana. “Unlike current AAV delivered gene therapy, our task is to use full length dystrophin gene therapy to dramatically improve patients suffering from devastating diseases.”
Added Debra Miller, CEO and founder of CureDuchenne, who will also join Myosana’s board of directors: “We’re very excited at the prospect of Myosana’s non-viral gene therapy offering full-length dystrophin to potentially treat 100% of the Duchenne population.”
“CureDuchenne extends our gratitude to those of the Duchenne community who have helped us raise the money used for this investment,” Miller added.