A Phase 2/3 Trial to Assess the Efficacy and Safety of OCU410ST for Stargardt Disease

Phase 2/3 Pivotal Confirmatory Clinical Trial is a randomized, outcome assessor-masked, multicenter study, that will enroll fifty-one (51) subjects. Subjects will be enrolled in a 2:1 ratio to either the treatment group (n=34 subjects) or to an untreated control group (n=17 subjects). Phase 1 is complete and closed for enrollment. It was a multicenter, open-label, dose ranging/dose escalation study that enrolled 9 subjects. OCU410ST Phase 1- Retinal Structure and Visual Function Data Results * Safety: Favorable safety and tolerability profile No SAE deemed related to OCU410ST including intraocular inflammation, exudation, endophthalmitis, anterior ischemic optic neuropathy (AIONs) or vasculitis. * Primary Endpoint: Structural Improvement Atrophic lesions grew slower by 48% at 12M in evaluable treated eyes when compared to untreated eyes * Secondary Endpoint: Visual Function (BCVA) 100% evaluable treated eyes demonstrated stabilization or improvement when compared to untreated eyes in visual function OCU410ST Phase 1- Structural and Functional Outcomes at 12M Data Results * The GARDian3 clinical trial for ABCA4- related retinopathies including Stargardt disease builds upon encouraging results and positive data from the Phase 1 GARDian trial, which demonstrated 48% slower lesion growth at 12-month follow-up in evaluable treated eyes compared to untreated eyes * Additionally, evaluable treated eyes showed a statistically significant (p=0.031) and clinically meaningful improvement of nearly 2-line/9-letter gain in best corrected visual acuity (BCVA) at 12-month follow-up when compared to untreated eyes.

Phase 2/3 Inclusion Criteria (applicable for both adult and pediatric subjects): 1. Males or females aged ≥5 years at the time of consent. 2. Subjects who have confirmed clinical and CLIA certified or equivalent genetic diagnosis of Stargardt disease (including ABCA4 related retinopathies). 3. Adult subjects who have BCVA of 75 letters or less in the study eye (20/32 Snellen equivalent) and Pediatric subjects who have a BCVA of 35 letters or better in the study eye (20/200 Snellen equivalent). 4. The study eye should have at least one well-demarcated area of atrophy with a minimum diameter of 300 microns, and total lesion size must add to less than or equal to ≤ 18 mm\^2 (approximately 7-disc areas). 5. Have detectable outer nuclear layer (ONL) in the macular region Phase 2/3 Exclusion Criteria (applicable for both adult and pediatric subjects): 1. Participation in ongoing antiretroviral therapy treatment. 2. Participation in any investigational therapy study or receipt of investigational treatment within 60 days prior to screening or 5 half-lives (whichever is longer). Any ophthalmic history of gene therapy, stem cell therapy, surgical implantation of prosthetic retinal chips, intravitreal or subretinal injections, or participation in an Alkeus ALK-001 study within the past 6 months. 3. Macular atrophy secondary to any disease other than Stargardt Disease (STGD). 4. Presence of genetic mutations that mimic Stargardt Disease like ELOVL4, or PROM1. 5. Contraindication to subretinal injection or use of anesthesia (local and/or general). Phase 1 was a multicenter, open-label, dose-ranging/dose escalation study. Enrollment is complete for Phase 1