Trial To Assess Efficacy Of A Chimeric Skin In Patients With Epidermolysys Bullosa

Inclusion criteria: * Patients of both sexes over 28 days of age. * Patients with recessive dystrophic epidermolysis bullosa diagnosed by clinical and historical criteria with severe skin syndactyly in whom reconstructive surgery is indicated. * Patients whose legal guardians have given written informed consent for participation in the study before any study procedure is performed. * Patients aged ≥ 12 years who have given written informed consent for participation in the study before any study procedure is performed. Exclusion criteria: * Women of childbearing age not using effective contraceptive methods (oral contraception) * Pregnant or nursing women * Documented or suspected hypersensitivity to any of the therapeutic agents included in the study, including anaesthetic drugs. * Patients with a history of malignant tumor in the past 5 years * Patients with a diagnosis of active tuberculosis at the time of recruitment * Patients with prior positive markers for any of the following pathogens: hepatitis b and c, hiv-1 and hiv-2 * Patients with a history of clinically relevant hepatic, gastrointestinal, haematological, pulmonary, or neurological disease no directly related to epidermolysis bullosa. * Any other medical condition which, in the investigator´s judgment, might interfere with optimal participation in the study or involve a significant risk for the patient. * Alcoholism, drug addiction, psychiatric disorders, or other factors present in legal guardians which,in the investigator´s judgment may complicate patient participation in the study.