In the phase 1/2 dose-escalation trials for RPE65-associated LCA, choroideremia, and retinitis pigmentosa GTPase regulator (RPGR)-associated X-linked retinitis pigmentosa, patients receiving higher doses of AAV have presented with various signs of retinal inflammation, including vitritis, retinitis, and choroiditis,2,6,7 implicating the presence of a cell-mediated immune response. This evidence concerns the gene RPGR and retinitis.