A Study Comparing KB803 and Matched Placebo in Patients With Dystrophic Epidermolysis Bullosa

Inclusion Criteria:

1. The subject and/or their parent/legal guardian must provide informed consent/assentand must be able to and willing to follow study procedures and instructions.

2. Age 6 months or older at time of informed consent/assent.

3. Confirmed diagnosis of DEB with a mutation in the COL7A1 gene.

4. Meets minimum corneal abrasion symptom frequency in the NHS study.

Exclusion Criteria:

1. Initiation of any new treatment regimen or change in treatment for ocular diseaseduring the run-in period except for preservative free topical antibiotics orartificial tears/lubricants associated with standard of care treatment of cornealabrasions.

2. Treatment with an investigational agent or off-label ophthalmic use of an approvedproduct during the run-in period or planned use during the study (Exceptions may beapproved by the medical monitor on a case-by-case basis).

3. Any condition that, in the opinion of the Investigator, would impact the completionof all study-related assessments, interfere with the administration of study drug,and/or poses an additional risk to the subject.

4. Women who are pregnant or nursing.

5. Subject who is unwilling to comply with contraception requirements per protocol.

6. Subject is known to be noncompliant or is unlikely to comply with the requirementsof the study protocol in the opinion of the Investigator.