Viltolarsen (Viltepso) has shown promise in the treatment of Duchenne muscular dystrophy (DMD) in boys and men, as evidenced by the results of the open-label, phase II Galactic53 trial. The therapy, which involves exon skipping, demonstrated favorable safety profiles and potential clinical benefits in pulmonary function among participants, as reported during a late-breaking poster session at the American Academy of Neurology annual meeting.
One of the key findings of the study was the positive impact of viltolarsen on pulmonary function, as reflected in the increased or stabilized forced vital capacity (FVC%p) in ambulatory participants. Additionally, nonambulatory patients on viltolarsen experienced an increase in FVC%p, while those in the control group saw a decrease. This data is particularly significant as it indicates a potential treatment benefit for patients with DMD amenable to exon 53-skipping therapy.
DMD is a debilitating condition primarily affecting boys, characterized by mutations in the dystrophin gene leading to muscle weakness and damage. As the disease progresses, pulmonary function becomes compromised, eventually necessitating assisted ventilation. Exon-skipping therapies like viltolarsen work by skipping parts of the mutated gene, resulting in a shorter but functional dystrophin protein. This approach offers hope for patients with DMD by addressing the underlying genetic mutations.
Viltolarsen received accelerated approval from the FDA in 2020, paving the way for further clinical investigations. A phase III trial is currently underway to confirm the clinical benefits of the drug in DMD patients with exon 53 mutations. This regulatory approval adds viltolarsen to the list of exon-skipping therapies approved for DMD, including golodirsen and eteplirsen. These treatments offer a targeted approach to managing the genetic defects associated with the disease.
The Galactic53 trial involved 20 ambulatory and nonambulatory males receiving viltolarsen intravenously once weekly, compared to a control group from the Cooperative International Neuromuscular Research Group Duchenne Natural History Study. Participants on viltolarsen experienced mild-to-moderate treatment-emergent adverse events, with no serious complications or treatment discontinuations. The study also assessed peak cough flow (PCF) as an exploratory endpoint, showing improvements in both ambulatory and nonambulatory patients on viltolarsen.
Overall, the findings from the Galactic53 trial highlight the potential of viltolarsen in improving pulmonary function and overall clinical outcomes in DMD patients. The therapy offers a targeted approach to addressing the underlying genetic mutations responsible for the disease, providing hope for those affected by this devastating condition. Further research and clinical trials are needed to fully understand the long-term benefits and risks associated with viltolarsen and other exon-skipping therapies in the treatment of DMD.