This study is an open-label, single ascending dose clinical trial in participants who have ABCA4-related retinopathies. This is the first-in-human clinical trial in which ACDN-01 will be evaluated for safety, tolerability, and preliminary efficacy following a single subretinal injection of ACDN-01.

This is an open-label, single ascending dose study of ACDN-01 in adult participants with ABCA4-related retinopathy. The study is designed to evaluate the safety, tolerability, and evidence of biological effect of SAD levels (low, medium, and high) of ACDN-01 when delivered subretinally.

Participants will be followed on study for 2 years for the primary safety and preliminary efficacy endpoints, after which they will continue in the study in a 3-year long-term follow-up period, for a total study duration of 5 years.

Key Inclusion Criteria:

• Presence of mutations in the ABCA4 gene
• ABCA4 retinopathy phenotype (Stargardt disease type 1 or cone-rod dystrophy)
• Area of atrophy located in the macula of the study eye
• BCVA of 20/50 (0.4 logMAR) or worse

Key Exclusion Criteria:

• The presence of pathogenic or likely pathogenic mutations in other genes known to cause cone-rod dystrophy or Stargardt maculopathy
• Retinal disease other than ABCA4-related retinopathy
• Presence of a medical condition (systemic or ophthalmic), psychiatric condition, including substance abuse disorder, or physical examination or laboratory finding that may in the opinion of the principal investigator and sponsor preclude adherence to the scheduled study visits, safe participation in the study, or affect the results of the study.