Skeletal muscle weakness, heart problems and breathing difficulties are typically part of life for children living with Duchenne muscular dystrophy and other inherited muscular disorders.
Although many inherited muscular disorders don’t have a cure, researchers like Dr. Barry J. Byrne from the University of Florida are finding treatments to improve their quality of life.
Byrne is professor and associate chair for the Department of Pediatrics at UF’s College of Medicine as well as director of the Powell Gene Therapy Center.
Originally a pediatric cardiologist, Byrne arrived at UF from Johns Hopkins University in Baltimore. In the late 1990s, his lab discovered the potential use of adeno-associated virus (AAV) vectors to reach and treat muscle cells. “At the time, there were no therapies for inherited muscular disorders,” he says.
AAV vectors are small viruses used to deliver genes to the body without actually causing disease. AAV gene therapies can help edit or replace problem genes.
Byrne and colleagues’ work with AAV vectors has led to therapies that improve cardiac and muscle function for children with Duchenne muscular dystrophy, Friedreich’s ataxia and other rare inherited neuromuscular disorders.
His lab also established methods for the production of AAV vectors so that other labs could study AAV and develop clinical products.
“My lab was the first to identify the ability of AAV vectors to reach muscle cells. We now have an approved therapy for spinal muscular atrophy and Duchenne muscular dystrophy,” Byrne says.
Byrne was a 2024 inductee into the Florida Inventors Hall of Fame. He has founded four startup companies in Florida and holds 25 U.S. patents.
Although AAV-guided gene therapy is effective, one major priority is improving its safety, Byrne says. The body can still react to AAV as a foreign invader, leading to immune system reactions and other toxicity throughout the body. There have been several deaths associated with AAV vector therapy, so safety and finding the right dosing remain crucial, he adds.
Another challenge is developing therapies for less common inherited diseases. “Only the more common diseases that have a U.S. prevalence of greater than 1,000 individuals are being actively developed as therapy. The ones that are smaller are not more challenging scientifically, but it’s harder to make the economic argument for the drug development cost,” Byrne says.
Options to provide treatment for patients with these less common disorders are underway, such as offering the therapy at cost or via clinical trials.
Identifying genetic diseases in newborns and infants is also part of the puzzle — something that the new Florida Sunshine Genetics Act can help address, Byrne says. The act aims to provide more newborn screening and research for pediatric rare diseases.