Each subject will receive a central subretinal injection of AGTC-501 at the assigned dose in the central macula of the study eye. primaryPurpose: TREATMENT masking: QUADRUPLE maskingDescription: The Phase 2 study is a masked study; therefore, neither the investigator nor the subject will know the dose assignment. Both the subject and the investigator will know which eye received treatment. whoMasked: PARTICIPANT whoMasked: CARE_PROVIDER whoMasked: INVESTIGATOR whoMasked: OUTCOMES_ASSESSOR count: 14 type: ACTUAL name: rAAV2tYF-GRK1-RPGR measure: The difference in the proportion of responding eyes between treated and control eyes in the low dose group and high dose group at 12 months, as measured by MAIA microperimetry, where response is defined as a 7dB or more improvement in at least 5 loci. measure: Proportion of responding eyes in treated eyes versus control eyes in the low dose group and the high dose group at Month 12 where responder is defined as an ORA-VNC mobility test score improvement of 2 or more luminance levels. measure: Proportion of responding eyes in treated versus control eyes in the low dose group and the high dose group at Month 12, as measured by MAIA microperimetry, where responder is defined as a 7 dB or more improvement in at least 5 loci within bleb. measure: Proportion of responding eyes in treated vs control eyes in the low dose group and the high dose group at Month 12, measured by MAIA microperimetry where responder is defined as 7 dB or more improvement in at least 5 loci within the central 16 loci measure: Difference in mean change from baseline in the central 36 loci (C36) mean sensitivity, as measured by MAIA microperimetry, in treated eyes versus control eyes in the low dose group and high dose group at Month 12. measure: Difference in mean change from baseline in "within bleb" mean sensitivity, as measured by MAIA microperimetry, in treated eyes versus control eyes in the low dose group and high dose group at Month 12. measure: Difference in mean change from baseline in central 10 degrees of vision on light adapted static perimetry, as measured by Octopus 900, in treated eyes versus control eyes in the low dose group and high dose group at Month 12. measure: Difference in mean change from baseline in BCVA, as measured by ETDRS or tumbling "E" chart, in treated eyes versus control eyes in the low dose group and high dose group at Month 12. measure: Proportion of responding eyes in treated versus control eyes in the low dose group and high dose group at Month 12 where responder is defined as a 10-letter vision gain as measured by ETDRS or tumbling "E" chart. measure: Difference in mean change from baseline in the EZ area, as measured by SD-OCT, in treated eyes versus control eyes in the low dose group and high dose group at Month 12 Visit. measure: Mean change from baseline in Impact of Vision Impairment (IVI) (Weih et al, 2002; Lamoureaux et al, 2007) or Impact of Vision Impairment for Children (IVI-C) (Cochrane et al, 2008) in the low dose group and high dose group at Month 12 Visit measure: Mean change from baseline in Patient Global Impressions of Change (PGI-C) and Patient Global Impressions of Severity (PGIS) in the low dose group and high dose group at Month 12 Visit. sex: MALE minimumAge: 8 Years maximumAge: 50 Years stdAges: CHILD stdAges: ADULT facility: University of Florida city: Jacksonville state: Florida zip: 32209 country: United States lat: 30.33218 lon: -81.65565 facility: Boston Children's Hosptial city: Boston state: Massachusetts zip: 02115 country: United States lat: 42.35843 lon: -71.05977 facility: Cincinnati Eye Institute city: Cincinnati state: Ohio zip: 45242 country: United States lat: 39.12713 lon: -84.51435 facility: Cleveland Clinic city: Cleveland state: Ohio zip: 44195 country: United States lat: 41.4995 lon: -81.69541 facility: Casey Eye Institute city: Portland state: Oregon zip: 97239 country: United States lat: 45.52345 lon: -122.67621 facility: Retina Foundation of the Southwest city: Dallas state: Texas zip: 75231 country: United States lat: 32.78306 lon: -96.80667 hasResults: False