A Study of FCX-007 for Recessive Dystrophic Epidermolysis Bullosa (DEFI-RDEB)

A Pivotal Phase 3 Study of FCX-007 (Genetically-Modified Autologous Human Dermal Fibroblasts) for Recessive Dystrophic Epidermolysis Bullosa

The purpose of this study is to determine whether administration of FCX-007 in addition to standard of care improves wound healing as compared to standard of care alone (control) in children, adolescents, and adults with Recessive Dystrophic Epidermolysis Bullosa. Funding Source - FDA OOPD

DEFI-RDEB is a multi-center, intra-patient randomized, controlled, open-label, Phase 3 study of FCX-007 for the treatment of persistent non-healing and recurrent RDEB wounds in approximately 24 subjects. Each subject will serve as his/her own control. Each subject's target wounds will be paired then randomized to receive FCX-007 (treatment wound) or remain untreated (control wound). Up to three target wound pairs will be identified for each subject. Subjects will receive intradermal injections of FCX-007 in each specified treatment wound in two or more treatment sessions. The first treatment session occurs at Day 1 and the second at Week 12/Month 3. Additional treatment sessions may occur at Week 24/Month 6 and Week 36/Month 9 when unclosed treatment wounds may be re-treated, and unclosed control wounds may be treated. Safety and efficacy assessments will occur at scheduled intervals through Week 48/Month 12, when the treatment period is completed, and a long-term safety follow-up period (through 15 years) commences for subjects who have received one or more FCX-007 injections.

Intra-subject randomized (paired wounds in each subject receive experimental treatment, FCX-007, or remain untreated). Up to three target wound pairs will be identified for each subject. Following pairing, target wounds will be randomly assigned as the treatment wound (FCX-007 is administered) or control wound. Subjects will receive intradermal injections of FCX-007 in each specified treatment wound in two or more treatment sessions. The first treatment session occurs at Day 1 and the second at Week 12/Month 3. Additional treatment sessions may occur at Week 24/Month 6 and Week 36/Month 9 when unclosed treatment wounds may be re-treated, and unclosed control wounds may be treated.

FCX-007 is comprised of fibroblasts isolated from the subject's skin biopsies which are genetically corrected with the full length COL7A1 gene encoding for type VII collagen.

Key Inclusion Criteria: Male or female ≥2 years of age at the Screening visit. Clinical diagnosis of RDEB with confirmation of COL7A1 genetic mutation. Key Exclusion Criteria: Medical instability limiting ability to travel to the investigative site. Active infection with human immunodeficiency virus, hepatitis B or hepatitis C. The presence of COL7 antibodies. Evidence of systemic infection. Evidence or history of squamous cell carcinoma at the site to be injected. Evidence of or history of metastatic squamous cell carcinoma. Known allergy to any of the constituents of the product. Female who is pregnant or breastfeeding. Receipt of a chemical or biological intervention for the specific treatment of RDEB in the past three (3) months prior to screening or anticipated/planned during the screening and treatment period for this study.