Electroretinography in assessing the effectiveness of Retinalamin in age-related macular degeneration

Positive results of clinical trials (CIs) on the use of Retinalamin in patients with various diseases of the optic nerve and retina have been documented in the literature. To improve the objectivity of the study results and minimize bias, we conducted a randomized controlled clinical trial, the design of which included the formation of parallel groups treated with Retinalamin and placebo. The purpose of the study was to evaluate the dynamics of electroretinography (ERG) parameters in patients with dry and wet age-related macular degeneration (AMD) over two years during “Retinalamin” therapy. Material and methods. The study included 21 patients with eаrly or intermediate stage of dry AMD in one eye and wet AMD in the other eye. Patients were randomly divided into 2 groups: main (“Retinalamin”) and control (placebo) groups. Participants received the drugs intramuscularly (a total of 8 courses of 10 days with an interval of 90 days). Cone ERG (ISCEV), multifocal ERG (mfERG) and macular ERG (MERG) were recorded dynamically. The observation period was 720 days (2 years) with repeat ERG at 90, 180, 270, 360, 540 and 720 days after the start of CI. A comprehensive statistical analysis was used to evaluate the ERG results in all groups and for intergroup comparison. Results. The therapeutic effect of “Retinalamin” was detected in eyes with both dry and wet AMD. In the dry AMD subgroup, the effect was more pronounced and for a larger number of ERG parameters. The stability of the effect was confirmed by the results of the Friedman analysis with the Bonferroni correction and in linear mixed models. For most parameters, the proportion of patients who achieved the specified threshold values was higher in the “Retinalamin” group. Conclusion. A statistically significant advantage of “Retinalamin” over placebo was demonstrated for most parameters. The effect size (“large”), based on Cohen’s d coefficients for the amplitude density and latency of the P1 component for all mfERG rings, and the amplitude and latency of the a- and b-MERG waves, indicates a clinically significant effect of “Retinalamin”.