By Melanie Karniewich, Class of 2025
Epidermolysis bullosa (EB) is a rare genetic condition that causes serious blisters to the skin from minor occurrences like rubbing or scratching the skin. In severe cases, blistering can happen inside the body like the mouth or lining of the stomach. Mutations in EB disable genes for the specific proteins that allow the layers of someone’s skin and the lining of organs inside the body to stay together. Peter Marinkovich, PeiPei Zhan, and colleagues developed a gel to apply to external blisters that contain a modified herpes simplex virus 1. This virus carries a gene missing from those with EB.
Broken up into two phases for the trial, they gathered males and females over 6 years old that were diagnosed with EB. Starting with 9 patients for the trial, during phase one, the researchers split up the total number of wounds from all the patients into 2 groups: one getting a placebo and the other receiving the gel treatment. There were 10 wounds under no treatment and 18 wounds that received the gel containing the modified simplex, which resembled the missing protein. In this particular trial, they focused on the missing skin protein collagen VII that is resembled through modification of the herpes simplex virus 1, which is best known for causing cold sores. During phase 2, the researchers reviewed the wounds and found that in the gel group, all were able to heal except for one that needed a second round of gel treatment. The wounds in the placebo group were able to heal; however, they would reopen or regress from the three month period. While the gel treatment may seem promising, the gel doesn’t go far into the skin to prevent the blisters all together, so it would need to be reapplied when the dead skin comes off and the still-injured skin layer migrates to the top from below.
Since this is not a permanent cure for EB, researchers could consider improving the gel for a solution that prevents the outside blisters altogether. Scientists could also use gene therapy to correct the DNA sequence of herpes to help change treatment for Epidermolysis bullosa.
 I. Gurevich, P. Agarwal, P. Zhang, et al. In vivo topical gene therapy for recessive dystrophic epidermolysis bullosa: a phase 1 and 2 trial. Nat Med 28, 780–788 (2022). Doi: https://doi.org/10.1038/s41591-022-01737-y