A decision making algorithm for inherited retinal dystrophies, caused by biallelic mutations in the RPE65 gene, in the clinical practice of an ophthalmologist

Inherited retinal dystrophies (IRD) include a wide range of genetically and phenotypically heterogeneous diseases that lead to progressive loss of vision. With the development of gene therapy, it has become possible to treat two forms of IRD caused by biallelic mutations in the RPE65 gene: isolated retinitis pigmentosa (IRP) type 20 and Leber's congenital amaurosis (LCA) type 2. These nosologies are included in the list of orphan diseases of the Russian Ministry of Health. The success factor for the use of IRD gene therapy is the early stage of the disease, when the viability of retinal cells is preserved. An interdisciplinary approach to diagnostics makes it possible to timely establish the clinical and genetic variant of IRD and refer the patient to targeted therapy. Therefore, at a joint meeting of the Council of Experts of the North-Western Federal District of the Russian Federation, which included ophthalmologists and medical geneticists, a scheme for managing patients with IRD was accepted, including the stages of clinical and functional ophthalmological examination and molecular genetic testing. In addition, regional centers of expertise for IRD were approved in two federal medical institutions in St. Petersburg, whose task is to optimize the quality of diagnosing patients with IRP and LCA.

1. Recommendations on Clinical Assessment of Patients with Inherited Retinal Degenerations - 2016. https://www.aao.org/clinical-statement/recommendations-on-clinical-assessment-of-patients. Available at: https://www.aao.org/clinical-statement/recommendations-on-clinical-assessment-of-patients. (accessed 14.10.2021).

2. Neroev V.V., Katargina L.A., Kadyshev V.V., Zolnikova I.V., Kutsev S.I. Prospects for the diagnosis and gene therapy of inherited retinal dystrophies caused by biallelic mutations in the RPE65 gene. Russian ophthalmological journal. 2021; 14 (3): 78–82 (in Russian)]. https://doi.org/10.21516/2072-0076-2021-14-3-78-82

3. Chung D. C., Bertelsen M., Lorenz B., et al. The natural history of inherited retinal dystrophy due to biallelic mutations in the RPE65 gene. Am. Journ. Ophthalmol. 2019; 199: 58–70. doi: 10.1016/j.ajo.2018.09.024

4. Russell S., Bennett J., Wellman J.A., et al. Efficacy and safety of voretigene neparvovec (AAV2-hRPE65v2) in patients with RPE65-mediated inherited retinal dystrophy: a randomised, controlled, open-label, phase 3 trial. Lancet. 2017; 390 (10097): 849–60. http://dx.doi.org/10.1016/S0140-6736(17)31868-8

5. Bennett J., Wellman J., Marshall K.A., et al. Safety and durability of effect of contralateral-eye administration of AAV2 gene therapy in patients with childhood-onset blindness caused by RPE65 mutations: a follow-on phase 1 trial. Lancet. 2016; 388(10045): 661–72. http://dx.doi.org/10.1016/s0140-6736(16)30371-3