The aim of this clinical trial is to investigate the safety and efficacy of allo-APZ2-OTS administered intravenously to subjects with recessive dystrophic epidermolysis bullosa (RDEB) compared to placebo. An additional baseline-controlled open-label arm will be included to investigate the safety and efficacy of allo-APZ2-OTS administered intravenously to subjects with JEB and to RDEB subjects < 1 year.

Inclusion Criteria:

1. Male or female subjects with a diagnosis of RDEB or JEB confirmed by genetic testing or by a skin biopsy with immunofluorescence mapping (IFM). A minimal body weight of at least 5 kg is required;
2. Subject is eligible to participate in this clinical trial based on general health condition;
3. Subject with a target wound meeting the following criteria: 5-50 cm2, and < 9 months, no signs of acute infection;
4. Patient/legal representative understands the nature of the procedure and provide written informed consent/assent prior to any clinical trial procedure;
5. Women of childbearing potential must have a negative urine pregnancy test at Visit 1. Women of childbearing potential, male participants, and their partner must be willing to use highly effective contraceptive methods during the course of the entire clinical trial.

Exclusion Criteria:

1. Signs and/or a history of skin precancerous and cancerous lesions at screening or any current tumor diseases, including squamous cell carcinoma and basal cell carcinoma;
2. Known chronic lung disease;
3. Clinically significant laboratory values for coagulation and thrombocytes at screening;
4. Thromboembolic events of any grade in medical history;
5. Immunoreactions of any grade in medical history;
6. Any known allergies to components of the IP or premedication;
7. Patient/legal representative anticipated to be unwilling or unable to comply with the requirements of the protocol;
8. Pregnant or lactating women;
9. Current or previous (within 30 days of screening) treatment with another IP, or participation and/or under follow-up in another interventional clinical trial;
10. Previous participation in this clinical trial (except for screening failures);
11. Clinically significant or unstable concurrent disease or other clinical contraindications like an uncontrolled or poorly controlled mental health condition of the subject and/or his/her legal representative that could impact on patient's safety or interfere with study compliance such as inability to attend scheduled study visits;
12. Employees of the sponsor, or employees or relatives of the investigator.