A Comprehensive Review of Clinically Applied Adeno-Associated Virus-Based Gene Therapies for Ocular Disease

The eye is an ideal target for gene therapy due its accessibility, immune privilege, small size, and compartmentalization. Adeno-associated virus (AAV) is the gold standard vector for gene delivery and can be injected via multiple routes of administration to target different parts of this organ. The approval of Luxturna (TM), a subretinally delivered gene therapy for RPE65-associated Leber's congenital amaurosis, and the large number of successful proof of concept studies performed in animal models injected great momentum into the pursuit of additional AAV-based gene therapies for the treatment of retinal disease. This review provides a comprehensive summary of all subretinally, intravitreally, and suprachoroidally delivered AAV-based ocular gene therapies that have progressed to clinical stage. Attention is given to primary (safety) and secondary (efficacy) outcomes, or lack thereof. Lessons learned and future directions are addressed, both of which point to optimism that the ocular gene therapy field is poised for continued momentum and additional regulatory approvals.