Patient reported outcomes following EB-101 treatment of recessive dystrophic epidermolysis bullosa (rdeb) wounds showed durable wound healing and reduction in disease burden

RDEB is an ultra-rare, severe, inherited collagen disorder caused by the absence of type VII collagen. Manifestations include fragility of stratified squamous epithelium, painful blistering, delayed or impaired wound healing, large, chronic severely painful wounds, increased risk of infection, malnutrition, invasive squamous cell carcinoma and premature mortality. We report long-term patient-reported outcomes following treatment of large, chronic RDEB wounds with the gene-corrected autologous cell therapy EB-101. Large RDEB wounds that remained unhealed for ≥12 weeks were treated with 35 cm2 gene-corrected keratinocyte sheets (EB-101). Up to 6 sheets were transplanted in each of 7 adult participants. 3 to 6 years after initial treatment, participants were asked to rate change in wound pain, for treated and control wounds, compared with their pre-treatment state using a seven-point scale, ranging from 1 (very much improved) to 7 (very much worse). Investigator assessment of wound healing data from the last visit was recorded for each responder. Responses were received from 5 participants with 27 treated chronic wounds and 5 chronic, untreated (control) wounds. 59% (16) of treated wounds had > 50% healing, of which 75% (12/16) had healing of > 75%. Compared to pre-treatment state, 67% (18/27) of treated wounds had improved pain (scores < 4), with much or very much improved pain (scores of 1-2) reported for treated wounds with > 50% healing (9/16, 56%). Pain improvement was not reported for control wounds, with 4/5 wounds having no change and 1/5 wounds having worse pain (score of 5). Four responders (4/5) reported willingness to undergo another EB-101 treatment, and 1 responder did not as he did not experience improvement. EB-101 treatment resulted in significant long-term wound healing and patient-reported reductions in wound-related pain in most treated large, chronic RDEB wounds.