This is an open-label follow up study to evaluate the safety for the subjects with ALLO-ASC-DFU treatment in phase 1/2 clinical trial(ALLO-ASC-EB-101) for 24 months.

This is an open-label follow up study to evaluate the efficacy and safety for the subjects with ALLO-ASC-DFU treatment in phase 1/2 clinical trial (ALLO-ASC-EB-101) for 24 months.

ALLO-ASC-DFU is a hydrogel sheet containing allogenic adipose-derived mesenchymal stem cells. Adipose-derived stem cells have anti-inflammatory effect and release growth factors such as vascular endothelial growth factor(VEGF) and hepatocyte growth factor (HGF), which can enhance wound healing and regeneration of new tissue, finally may provide a new option in treating a Dystrophic Epidermolysis Bullosa.

Inclusion Criteria:

1. Subjects who are treated with ALLO-ASC-DFU sheet in phase 1/2 clinical trial of ALLO-ASC-EB-101.
2. A subject who is willing to follow the protocol and provide informed consent on screening, given that the information with respect to the clinical trial is provided.

Exclusion Criteria:

1. Subjects who are considered not suitable for the study by the principal investigator.

Subject is enrolled who are treated with ALLO-ASC-DFU sheet in phase 1/2 clinical trial of ALLO-ASC-EB-101