Pivotal 1 Study of ABBV-RGX-314 (Also Known as RGX-314) Gene Therapy Administered Via Subretinal Delivery One Time in Participants With nAMD

Inclusion Criteria: 1. Age ≥ 50 years and ≤ 89 years 2. An ETDRS BCVA letter score between ≤ 78 and ≥ 40 in the study eye 3. Diagnosis of subfoveal CNV secondary to AMD in the study eye previously treated with anti-VEGF 4. Must be pseudophakic (at least 12 weeks postcataract surgery) in the study eye. 5. Willing and able to provide written, signed informed consent for this study 6. Participants must have demonstrated a meaningful response to anti-VEGF therapy at study entry Inclusion Criteria (Bilateral Treatment Substudy)\*: 1. An ETDRS BCVA letter score between ≤ 83 and ≥ 40 in both eyes 2. Diagnosis of subfoveal choroidal neovascularization (CNV) secondary to AMD in both eyes 3. Must be pseudophakic (at least 12 weeks postcataract surgery) in both eyes 4. Willing and able to provide written, signed informed consent for this study 5. Newcomers must have active disease in the study eye; crossover participants must have active disease in the eye not treated in the main study Exclusion Criteria: 1. CNV or macular edema in the study eye secondary to any causes other than AMD 2. Subfoveal fibrosis or atrophy in the study eye, as determined by CRC 3. Any condition in the investigator's opinion that could limit VA improvement in the study eye 4. Active or history of retinal detachment, or current retinal tear that cannot be treated, in the study eye 5. Advanced glaucoma or history of secondary glaucoma in the study eye 6. History of intraocular surgery in the study eye within 12 weeks prior to randomization 7. History of intravitreal therapy in the study eye, such as intravitreal steroid injection or investigational product, other than anti-VEGF therapy, in the 6 months prior to Screening Visit 1 8. Prior treatment with gene therapy 9. Recent myocardial infarction, cerebrovascular accident, or transient ischemic attack within the past 6 months Exclusion Criteria (Bilateral Treatment Substudy)\*: 1. CNV or macular edema in either eye secondary to any causes other than AMD 2. Subfoveal fibrosis or atrophy in either eye 3. Any condition in the investigator's opinion that could limit VA improvement in either eye 4. Active or history of retinal detachment, or current retinal tear that cannot be treated in either eye 5. Advanced glaucoma or history of secondary glaucoma in either eye 6. Myocardial infarction, cerebrovascular accident, or transient ischemic attack within the past 6 months 7. History of intraocular surgery in either eye within 12 weeks prior to randomization (Week -2) 8. History of intravitreal therapy in either eye, such as intravitreal steroid injection or investigational product, other than anti-VEGF therapy, in the 6 months prior to screening 9. Prior treatment with gene therapy (\*) For previously treated crossover participants, criteria apply to the eye not treated in the main study only.