Bevacizumab is not toxic to retinal ganglion cells after repeated intravitreal injection.

Abstract

The cytotoxicity of single and repeated administration of bevacizumab to retinal ganglion cells was studied in vivo and in vitro. Rats received single or repeated injections of 125 microg of bevacizumab into the vitreous cavity of the left eye, while saline was injected into the right eye as a control. In the repeated injection group, bevacizumab was injected at the same concentration once per week for 4 weeks. Retinal ganglion cells were retrogradely labeled with Fluorogold dye, and counted after kill at 0 and 6 months after treatment. In the in vitro study, PC12 cells were cultured in various concentrations of bevacizumab (0, 1, 2, 5, and 10 mg/mL) to model retinal ganglion cells exposure. Cell viability in each group was assessed by an MTT assay. There was no significant difference in retinal ganglion cell numbers between control and bevacizumab-treated eyes following either single or repeated injection, or did bevacizumab have any significant influence on PC12 cell viability in vitro. These results suggest that intravitreal injection of bevacizumab poses no risk to retinal ganglion cells, even after repeated application.