According to a story from BioPortfolio, the drug company Pfizer has recently presented data from its phase 1b clinical trial that tested the company’s experimental gene therapy PF-06939926, which is being developed to treat Duchenne muscular dystrophy, a progressive muscle wasting disorder. The data that the company presented was from preliminary findings that are based on results from only a portion of the study participants. The main focus of this early trial was to assess the tolerability and safety of the experimental therapy.
About Duchenne Muscular Dystrophy
Duchenne muscular dystrophy is a neuromuscular disease, and it is one of the more severe types of muscular dystrophy. It is characterized by progressive muscle weakness that usually begins around age four and worsens quickly. As an X-linked genetic disease, boys are mostly affected, with girls only occasionally displaying mild symptoms. The disease is caused by mutations of the dystrophin gene. Symptoms of Duchenne muscular dystrophy include falling, abnormal walking posture, eventual loss of walking ability, muscle fiber deformities, intellectual disability (not in all cases), enlargement of the tongue and calf muscles, skeletal deformities, muscle atrophy, heart abnormalities, and difficulty with breathing. Treatment includes a variety of medications and therapies that can help alleviate symptoms and slow disease progression. Lifespan is usually into the thirties with good care. Better treatments for this disease are urgently needed. To learn more about Duchenne muscular dystrophy, click here.
About The Trial
The trial, which is still ongoing, ultimately aims to recruit a total of 12 patients. These boys will be between the ages of 5 and 12. So far, half of the participants have been dosed with PF-06939926. Two dosages have been used: 1E14 vg/kg or 3E14 vg/kg. The safety results from the trial so far have indicated that the most common adverse events include fatigue, fever, vomiting, reduced appetite, and nausea. These side effects were reported within days following the administration of the therapy. Nearly all of these effects have subsided in a one to three week period.
All of the patients also had an immune response to the drug, with one being hospitalized and having to undergo dialysis temporarily until the response had subsided. Muscle biopsies from two months after the treatment detected the presence of mini dystrophin, suggesting that the PF-06939926 mechanism is working as expected. The levels detected corresponded with the dosing level of each patient.
Pfizer will continue to collect further data from this study and is also planning on larger scale, late stage trials for this therapy.