According to a story from BioSpace, a Phase 1/2 clinical trial testing SGT-001, an investigational treatment for Duchenne muscular dystrophy, has been plagued by problems with side effects and adverse events. The drug is being developed by Solid Biosciences. While the events have been fully resolved, only further study will reveal if the experimental drug will be safe enough for approval from the US Food and Drug Administration (FDA).
About Duchenne Muscular Dystrophy (DMD)
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.
Adverse Events During the Study
The most concerning adverse event involved a patient that was recently treated with SGT-001 and developed a gastrointestinal infection soon afterwards. While this was not linked directly to the drug, the patient experienced other abnormalities as well, such as a temporary decline in platelet count and temporary elevation of bilirubin (two double the normal maximum) and transaminases.
While the company is continuing to enroll patients in the study, these additional changes were reported to the FDA as directly related to the treatment. SGT-001 is a gene transfer therapy that utilizes an AAV vector to deliver a substance called microdystrophin to the patient. This is effectively meant to function as a surrogate for regular dystrophin, which is deficient in patients with the disease.
Last year the FDA placed a clinical hold on the trial, but it was ultimately lifted in June 2018. This latest report is the first indication since the lifting of the hold that there have been further issues with adverse events. With these safety concerns hanging in the air, the future of SGT-001 remains uncertain.