Advances and Challenges in Duchenne Muscular Dystrophy Gene Therapy

Recent developments in gene therapy offer new hope for individuals with Duchenne muscular dystrophy (DMD), a severe inherited disorder causing progressive muscle weakness. The American Academy of Neurology has released an Evidence in Focus article in the journal Neurology to inform clinicians, families, and researchers about the current state of this promising yet complex treatment.

Duchenne muscular dystrophy primarily affects young boys, typically manifesting between ages two and four. It results from the absence of dystrophin, a crucial protein that maintains muscle integrity. Without it, muscles gradually deteriorate, leading to loss of mobility and, eventually, life-threatening complications.

In June 2024, the FDA approved delandistrogene moxeparvovec, a groundbreaking gene therapy for DMD applicable to those aged four and older. This one-time infusion uses a disabled virus to deliver a miniature version of the dystrophin gene into muscle cells, aiming to produce a small but functional form of dystrophin. However, despite this advancement, the therapy has faced scrutiny because clinical trial results have not conclusively demonstrated significant improvements in motor functions, which measure movement capabilities.

The available evidence suggests that while the therapy might marginally slow the decline in motor abilities, the benefits are difficult to distinguish from effects caused by concurrent high-dose steroid treatments. Moreover, several safety concerns have been identified, including risks of muscle and heart inflammation, liver injury, low blood platelet count, and even death, emphasizing the need for careful monitoring.

Cost remains a major hurdle, with the treatment priced at approximately $3.2 million per infusion, excluding hospital, follow-up, and supportive care expenses. The high cost raises questions about access and insurance coverage, prompting patients and providers to weigh the potential benefits against financial considerations.

Experts stress the importance of ongoing clinical studies to evaluate both the short-term and long-term safety and efficacy of this gene therapy. Currently, it does not cure DMD or clearly extend lifespan, but it represents a significant step forward in the pursuit of effective treatments.

As research continues, the hope is that future therapies might achieve better outcomes and fewer side effects. Educating patients about the limitations and risks of current options is essential for informed decision-making. The field of genetic therapy for DMD is evolving, and each new discovery brings the potential for improved quality of life for those affected.

Source: https://medicalxpress.com/news/2025-05-high-exploring-advances-duchenne-muscular.html