I thought the dystrophin gene was too large to package into AAVs, thus the main difficulty in gene therapy as a solution for DMD. The article reads that they injected the dystrophin gene in the trial --- is this true or did they use the mini-dystrophin gene that was created to overcome the size problem?
Hi--This study did use a minidystrophin gene and it was completed over a year ago. I think the news here just had to do with one of the after-study analyses that showed that the viral carrier seems to be safe. The investigators created a special hybrid of two different viral strains. There was another publication about this same trial, which appeared in the New England Journal of Medicine, that suggested that some of the boys may have experienced an immune response to the mini-dystrophin protein, but this only showed up with a special kind of testing that looked for activated immune cells. The boys themselves didn't have any symptoms.
Sharon Hesterlee, Ph.D.
Sr Director of Research, PPMD
Hi Sharon, can you tell us anything about HT-100 clinical trial in DMD from Halo Therapeutics? Is this Utrophin upregulation or something else....
Hi Amit: This trial is in the design phase and is not yet up and running. HT-100 is not a utrophin regulator but rather an anti-fibrotic, so it's thought to block the scarring that comes with the loss of muscle cells. The company also thinks that it may help with regeneration.
Thanks Sharon. The website didn't give much details but I was curious since they seem to be aiming the trial directly with the DMD boys rather than the convetional healthy volunteers for safety, etc.