FDA Slaps Second Clinical Hold on Solid Biosciences’ DMD Gene Therapy Due to Adverse Event
After a serious adverse event was reported in a child dosed with an investigational treatment for Duchene Muscular Dystrophy, the U.S. Food and Drug Administration (FDA) has placed Solid Biosciences’ Phase I/II IGNITE DMD study on clinical hold, the second in a year’s time.
Share prices for Solid Biosciences have tumbled 65% in premarket trading after the company made the announcement late Monday. The IGNITE DMD study is assessing the company’s microdystrophin gene therapy asset SGT-001 as a potential treatment for DMD, the most common and severe form of muscular dystrophy that primarily affects boys. DMD causes a progressive loss of muscle strength attributable to a loss of a protein called dystrophin, which normally protects muscle fibers from breaking down. Approximately 15,000 U.S. patients are affected with Duchenne, with a total of 300,000 patients worldwide.
SGT-001 is a novel adeno-associated viral vector-mediated gene transfer under investigation for its ability to address the underlying genetic cause of DMD. SGT-001 is designed to deliver a synthetic dystrophin gene, called microdystrophin, to the body of DMD patients.
In its announcement, Solid Biosciences said a patient in its second cohort who was dosed in October experienced a serious adverse event that was deemed related to the drug. The serious adverse event was characterized by complement activation, a decrease in red blood cell count, acute kidney injury and cardio-pulmonary insufficiency, the company said. The patient was treated and is recovering and improving, Solid Biosciences added. However, as a result, the FDA placed the clinical hold on the trial. Solid Biosciences said it will work with the regulatory agency to resolve the hold and determine the next steps for the trial.
This marks the second clinical hold on the trial and the second round of adverse events-related issues in less than a year in the IGNITE DMD trial. Most recently, in a quarterly financial report earlier this year, Solid Biosciences reported that a patient treated with SGT-001 was diagnosed with a gastrointestinal infection. While it was believed that the issue was not related to the drug, it was classified as a serious adverse event. The patient also experienced a transient elevation of transaminases and a transient increase in bilirubin higher than two times the upper limit of normal. Additionally, that patient showed a transient decline in platelet count that was believed to be a non-serious adverse event related to the drug.
Last year, the FDA placed a clinical hold on the trial following the report of a serious adverse event. That hold was lifted in June 2018 after the company addressed the FDA’s concerns.
Ilan Ganot, chief executive officer and co-founder of Solid Biosciences, said the company remains committed to developing a DMD treatment and continues to “believe in the differentiated construct of SGT-001 and the potential benefits it may offer to patients.” Ganot said the company believes it will have a better understanding of the biological activity and potential benefit of SGT-001 in the coming weeks as it looks to resolve this clinical hold.
The clinical hold on Solid’s asset is the second bit of bad news the DMD community has received this month. Last week, Swiss pharma giant Roche announced it was terminating its study of an investigational anti-myostatin adnectin protein in ambulatory boys with DMD. Roche said an analysis of the ongoing data indicated that its treatment RG6206 was “highly unlikely” to demonstrate clinical benefit in the trial.