Phase 1/2 Open-Label Dose-Escalation Study to Evaluate Safety of a Single Intravitreal Injection of RTx-021 in Patients With Stargardt Disease

Inclusion Criteria:

* Male and female patients \>= 16 years of age
* Able to comply with the study visit schedule and all protocol assessments
* Diagnosis of Stargardt Disease (genetic testing required)
* Study eye and fellow eye Best Corrected Visual Acuity meeting study criteria
* Presence of retinal ganglion cells and/or retinal nerve fiber layer on Spectral Domain Optical Coherence Tomography testing at Screening confirmed by central image reading center
* Adequate organ function and general good health

Exclusion Criteria:

* Participation in a clinical study (ocular or non-ocular) with an investigational drug, agent, or therapy in the past six months
* Concurrent participation in another interventional clinical ocular study
* Prior receipt of any gene therapy (ocular or other), retinal implant, or ocular cell therapy
* Pre-existing eye conditions in either eye that would preclude the planned treatment or are significant enough to interfere with the interpretation of study endpoints or procedural complications
* Known steroid responders if their intraocular pressure was not able to be managed effectively with topical pressure-lowering medications after prior use of steroid medications
* Complicating systemic diseases including those in which the disease itself, or the treatment of the disease, can alter ocular and/or central nervous system function (e.g. radiation treatment of the orbit; leukemia with optic nerve involvement)
* Any immunological response dysfunction including, immuno-compromising diseases or use of immunosuppressive medications, among others
* Cataract or other ocular (including refractive) surgery, intraocular and/or peri-ocular injection in either eye within the prior four months (i.e. 120 days) prior to screening
* Prior vitrectomy or aphakia in the study eye
* Known sensitivity to any component of the study treatment or contraindication to medications planned for use in the peri-procedural period (e.g. povidone-iodine to prep for intravitreal injection)
* Known contraindication to prophylactic steroid regimen
* Current pregnancy or breastfeeding
* Any other condition that would not allow the patient to complete follow-up examinations during the study