Clinical efficacy of conbercept injection on neovascular age-related macular degeneration under different levels of inflammation.

Background: Age-related macular degeneration (AMD) is considered one of the most common causes of irreversible blindness among elderly patients. Neovascular AMD, which accounts for 10% of all AMD cases, can cause devastating vision loss due to choroidal neovascularization (CNV). The clinical effects and safety of intravitreal injection of conbercept in patients suffering from neovascular AMD have not been fully evaluated.

Objectives: The aim of the study was to evaluate the efficacy and safety of intravitreal injection of conbercept in patients with neovascular AMD with different levels of inflammation.

Material and methods: A total of 120 consecutive patients with neovascular AMD who underwent intravitreal injection of conbercept (3 injections per month + pro re nata (3 + PRN)) were included and stratified based on the intraocular level of high-sensitivity C-reactive protein (hs-CRP). The level of inflammation was defined as low, medium or high, based on the concentration of hs-CRP prior to injection. Before and after conbercept injections, best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were compared, respectively. Moreover, cytokine markers as well as the frequency of injections and adverse events (AEs) were measured.

Results: There were significant differences in BCVA and CRT between low, medium and high tertiles. Compared to the baseline, improved BCVA was observed, and CRT declined significantly after operation. Adverse events were most observed in high tertiles. A significant decrease in vascular endothelial growth factor (VEGF), interleukin (IL)-6 and IL-8 was observed after 1 year.

Conclusions: The effectiveness of conbercept on neovascular AMD varies depending on the level of inflammation, which could be achieved by administering different injection frequencies at different levels of inflammation. Furthermore, conbercept is associated with the reduction of inflammatory factor (IL-6 and IL-8) levels after intravitreal injection, which suggests that suppressing inflammatory response might contribute to the clinical efficacy of anti-VEGF treatment. Our results provide a novel mechanism for conbercept in patients with neovascular AMD.