RGX-314 Gene Therapy Administered in the Suprachoroidal Space for Participants With Diabetic Retinopathy (DR) With and Without Center Involved-Diabetic Macular Edema (CI-DME)

This phase 2, randomized, dose-escalation study is designed to evaluate the efficacy, safety and tolerability of ABBV-RGX-314 gene therapy in subjects with DR with and without center-involved diabetic macular edema (CI-DME). Part 1: For subjects with DR without CI-DME, approximately 100 participants who meet the inclusion/exclusion criteria will be enrolled into one of 5 cohorts. Participants will be randomized in Cohorts 1, 2, 4 and 5 to receive ABBV-RGX-314 or to be observed, and participants enrolled in Cohort 3 will receive ABBV-RGX-314. Cohort 1 will evaluate ABBV-RGX-314 Dose 1, Cohorts 2 and 3 will evaluate ABBV-RGX-314 Dose 2, and Cohorts 4 and 5 will evaluate ABBV-RGX-314 Dose 3. Following SCS ABBV-RGX-314 administration, participants in Cohorts 4 and 5 will receive a protocol-mandated post-procedure steroid regimen for 7 weeks. Participants who are randomized to be observed in Cohorts 1, 2, 4 and 5 will be offered ABBV-RGX-314 after completing the study. Part 2: For subjects with DR with CI-DME, approximately 30 participants who meet the inclusion/exclusion criteria will be enrolled into one cohort (Cohort A). Participants will be randomized to receive ABBV-RGX-314 or Aflibercept Control. Cohort A will evaluate ABBV-RGX-314 Dose 4. Participants randomized to receive SCS ABBV-RGX-314 will receive a protocol-mandated course of steroid. Participants who are randomized to the Aflibercept Control arm will be offered ABBV-RGX-314 after completing the study.