Source -MedCity News
The US Food and Drug Administration (FDA) has granted approval for the first gene therapy to treat a rare form of muscular dystrophy. This milestone allows the treatment to be available to a broader range of patients with the genetic mutation responsible for the disease.
Expanded Approval for Elevidys
The drug, Elevidys, developed by Sarepta Therapeutics, was initially approved last year for children aged 4 and 5 with Duchenne muscular dystrophy (DMD) who had a specific mutation in the DMD gene. DMD is one of the most severe forms of inherited muscular dystrophy, leading to progressive muscle degeneration and weakness. On Thursday, the FDA announced its decision to extend traditional approval for Elevidys to ambulatory patients aged 4 and older with the DMD mutation. Additionally, the FDA granted accelerated approval for non-ambulatory patients aged 4 and older with the same mutation. However, the agency stated there is insufficient safety data to support the use of Elevidys in children under 4.
Elevidys is administered as a one-time intravenous infusion and comes with a significant price tag of approximately $3.2 million per patient. Despite its high cost, it aligns with other one-time gene therapy, which often exceeds $3 million. Currently, Elevidys is the second most expensive drug globally, following Hemgenix, a hemophilia treatment priced at $3.5 million.
Addressing an Urgent Medical Need
The initial approval of Elevidys was granted under the FDA’s accelerated approval pathway, which allows for the expedited approval of treatments for serious conditions based on early evidence of potential benefits. Since its approval, Elevidys has been closely monitored. In October, Sarepta Therapeutics released data from a confirmatory trial, which showed that while the gene therapy did not meet its primary endpoint—a measure of children’s mobility—it did achieve several secondary outcomes.
Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, highlighted the significance of this approval. He described it as addressing “an urgent unmet medical need and an important advancement in the treatment of Duchenne muscular dystrophy, a devastating condition with limited treatment options, that leads to a progressive deterioration of an individual’s health over time.”
Duchenne muscular dystrophy primarily affects boys, with an estimated incidence of 1 in 3,300. The disease leads to progressive muscle weakness, often resulting in loss of the ability to walk by adolescence and significantly shortening life expectancy. The approval of Elevidys followed emotional testimonies from families during an FDA advisory committee meeting, underscoring the profound impact of DMD on patients and their loved ones.
The Muscular Dystrophy Association has expressed support for the FDA’s decision. Dr. Sharon Hesterlee, the association’s chief researcher, emphasized the importance of balancing the risks and benefits of the drug. “Ultimately, what we want is what’s best for our patient community – and that’s balancing that risk-benefit ratio appropriately,” she stated.
First Approved Gene Therapy for Muscular Dystrophy Brings Hope to Kids Everywhere
Potential risks associated with Elevidys include increases in liver enzyme levels and the possibility of acute serious liver injury. Common side effects include vomiting, nausea, elevated liver function tests, and fever. However, the significant benefit of this gene therapy is its single-dose administration, providing an additional treatment option for those with Duchenne muscular dystrophy.
Currently, there is no cure for Duchenne muscular dystrophy, and existing treatments are limited. Standard care often involves corticosteroids like prednisone, which come with undesirable side effects such as weight gain, behavioral issues, and increased risk of bone fractures. Other treatment options include physical therapy, certain drugs that modify how muscle cells interpret the mutated gene, and surgeries to correct spinal deformities.
With the FDA’s expanded approval of Elevidys, patients with Duchenne muscular dystrophy have a new, promising option in their fight against this debilitating disease.
