Junctional Epidermolysis Bullosa

This is a Phase 2, double-blind, randomized, vehicle-controlled study designed to evaluate efficacy, safety, and tolerability of topically applied TCP-25 gel in patients with confirmed DEB or JEB. The study will implement intrasubject randomization, ie, a pair of matching index wounds will be randomly assigned to be treated with a local application of either TCP 25 gel or vehicle gel.

The goal of this clinical trial is to learn if Oleogel-S10 gel works to treat skin wounds from two types of inherited epidermolysis bullosa (EB): junctional EB (JEB) or dystrophic EB (DEB) in the Japanese population. Children and adults may participate. The trial also looks at the safety of Oleogel-S10 gel. The main questions it will answer are: * Does Oleogel-S10 gel close wounds from JEB or DEB within 45 days or reduce the size of the wounds? * Are there any medical problems when using Oleogel-S10 gel? * How much of the drug ends up in your blood? The study has 2 parts. In Part 1, participants will: * Apply Oleogel-S10 gel to the EB wound dressings at least once every 4 days for 45 days. * Visit the clinic once every 2 weeks for checkups and tests. If participants complete Part 1, they may participate in Part 2 if they choose to. In Part 2, participants will continue to receive Oleogel-S10 gel until the product is available to buy in Japan or until the trial is stopped by the company.

Herlitz junctional epidermolysis bullosa (H-JEB), an incurable, fatal, inherited skin disease, is caused by loss-of-function mutations in the LAMA3, LAMB3 or LAMC2 genes, resulting in loss of laminin 332 and poor epidermal-dermal adherence. Eighty percent of H-JEB patients have LAMB3 mutations and about 95% of these are nonsense mutations. The investigators recently demonstrated that gentamicin readily induced nonsense mutation readthrough and produced full-length laminin beta3 in several nonsense mutations tested. Importantly, the gentamicin-induced laminin beta3 restored laminin 332 assembly, secretion, and deposition into the dermal-epidermal junction (DEJ). Newly induced laminin 332 reversed abnormal H-JEB cellular phenotypes. Herein, the investigators propose the first clinical trial of gentamicin (by topical and intravenous administration) in JEB patients with nonsense mutations. The milestones will include restored laminin 332 and hemidesmosomes at the DEJ, improved wound closure, and the absence of significant gentamicin side effects.