The news: Myosana Therapeutics, a Seattle startup developing gene therapy technology, raised $5 million to develop an early-stage candidate treatment for Duchenne muscular dystrophy (DMD). Mysona says its experimental platform to deliver genes to cells has advantages over the standard approach, which is limited to smaller pieces of DNA.
The people: Co-founders Stanley Froehner, a University of Washington professor of physiology and biophysics, and Nick Whitehead, a UW research associate professor, launched the company in 2018. Froehner serves as chairman and Whitehead as chief scientific officer.
Matthew Lumley, a partner at venture firm Medicxi who has served on Myosana’s board for more than a year, was appointed CEO in January. London-based Lumley was previously senior director of rare disease clinical development at Moderna and medical director of rare diseases at Pfizer; his son also has DMD, which leads to muscle weakness and atrophy.
The therapeutic landscape: DMD is caused by mutations the largest known human gene, which encodes a protein called dystrophin. Several companies, including Pfizer and Sarepta Therapeutics are developing gene therapies to introduce functional dystrophin DNA into cells using modified viruses called AAVs (adeno-associated viruses). But AAVs can’t handle large genes, so instead they are loaded up with a smaller piece of DNA that yields a truncated form of dystrophin.
Sarepta has asked the U.S. Food and Drug Administration for approval based on data showing that the introduced gene is active in cells; that decision is expected in the spring, and the company has raised $1.2 billion to market the therapy while it completes studies assessing clinical outcomes. Sarepta also markets three approved drugs that together aim to treat about 30% of DMD patients using a method called exon skipping.
Other experimental gene therapy delivery approaches include lipid nanoparticles, technology similar to that behind the COVID-19 RNA vaccines.
The tech: Myosana has developed antibodies that home to a protein on skeletal and cardiac muscle cells to deliver genes into them. The system can deliver large-sized genes, and it can may be used repeatedly, whereas AAV vectors are generally designed for single use because of the risk of developing immunity.
Data on Myosana’s system are not published, but Whitehead told GeekWire that they have used it to deliver the entire DMD gene to muscles in mice via intravenous injection.
The startup aims to use the new funding to help identify an early development candidate for DMD by 2025, but the platform has the potential for broad application. “As proof of principle for the platform, success in treating Duchenne would open up opportunities for Myosana to target a large range of neuromuscular and cardiac diseases,” said Lumley in a statement Wednesday announcing the funding.
The investors: The funding round was led by John Ballantyne, co-founder and former chief scientific officer of Fargo, N.D.-based Aldevron, a company that performs contract drug development and manufacturing services. In 2021, Ballantyne also co-founded Fargo-based Agathos Biologics, a startup focused on biomanufacturing and delivery of therapeutic molecules into cells.
Participants in the seed round are the Muscular Dystrophy Association, which contributed $650,000 and Parent Project Muscular Dystrophy, which contributed $500,000, building on a $350,480 investment in Myosana in August 2021. CureDuchenne Ventures was also an earlier investor in Myosana.