To determine whether administration of topical B-VEC improves wound healing as compared to placebo, and to evaluate durability, repeat dosing (Primary Endpoint) and further obtain safety and tolerability data.

Thirty-one (31) participants with DEB, aged 6 months or older at time of consent were enrolled for this Phase III study. The trial duration for each subject was about 6 months, with administration occurring once weekly. A Safety Follow-up Visit occurring 30 days from the date of final treatment with the Investigational Product also occurred. Each subject provided one pair of primary target wounds, with one wound from each pair randomized to be treated with B-VEC and the other wound with placebo. In addition to the primary target wound pair(s), additional wounds (secondary wounds) were selected to be treated with B-VEC. Throughout the study, participants complete questionnaires, had images captured of their study wounds, underwent physical exams, had vital signs and safety labs monitored.

Inclusion Criteria:

1. The subject or legally appointed and authorized representative must have read, understood and signed an Institutional Review Board/Ethics Committee (IRB/EC) approved Informed Consent or Assent Form and must be able to and willing to follow study procedures and instructions.

2. Age ≥ 6 months and older at the time of Informed Consent.

3. Clinical diagnosis of the Dystrophic Epidermolysis Bullosa.

4. Confirmation of DEB diagnosis (either DDEB or RDEB) by genetic testing including COL7A1.

5. Two (2) cutaneous wounds meeting the following criteria:

   1. Location: similar in size, located in similar anatomical regions, and have similar appearance
   2. Appearance: clean with adequate granulation tissue, excellent vascularization, and do not appear infected.

6. Subjects and caregivers who, in the opinion of the Investigator, are able to understand the study, co-operate with the study procedures and are willing to return to the clinic for all the required follow-up visits.

7. Male or Female of childbearing potential must use a reliable birth control method throughout the duration of the study and for three (3) months post last dose of B-VEC.

8. Negative pregnancy test at Visit 1 (Week 1), if applicable.

Exclusion Criteria:

1. Medical instability limiting ability to travel to the Investigative Center.
2. Diseases or conditions that could interfere with the assessment of safety and efficacy of the study treatment and compliance of the subject with study visits/procedures, as determined by the Investigator.
3. Current evidence or a history of squamous cell carcinoma in the area that will undergo treatment.
4. Subjects actively receiving chemotherapy or immunotherapy at Visit 1 (Week 1).
5. Active drug or alcohol addiction as determined by the Investigator.
6. Hypersensitivity to local anesthesia (lidocaine/prilocaine cream).
7. Participation in an interventional clinical trial within the past three (3) months (not including BVEC administration).
8. Receipt of a skin graft in the past three (3) months.
9. Pregnant or nursing women.

Safety Population

6 months