Alterations in intraocular cytokine levels following intravitreal ranibizumab

Abstract

Objective: Our previous work has shown that, after intravitreal bevacizumab (IVB) administration, decreases in the levels of vascular endothelial growth factor (VEGF)-A and placental growth factor (PlGF), along with increases in the levels of interleukin (IL)-8 and transforming growth factor (TGF)-β2, can be observed. It is not yet known if similar changes occur after intravitreal ranibizumab (IVR). The purpose of this study was to examine intraocular cytokine changes after IVR.

Design: Prospective clinical study.

Participants: Subjects with proliferative diabetic retinopathy requiring pars plana vitrectomy (PPV) were recruited.

Methods: Participants received IVR as pre-treatment before PPV. Aqueous humour levels of IL-8, VEGF-A, PlGF, and TGF-β2 were measured at time of pre-treatment and PPV. Results were analyzed using univariate statistical models.

Results: A total of 14 participants were recruited. After IVR administration, we observed a decrease in the levels of VEGF-A and PlGF, and an increase in the levels of IL-8 and TGF-β2. These results were statistically significant only for VEGF-A (p = 0.0001) and IL-8 (p = 0.0002).

Conclusions: The changes in cytokine levels after IVR mirror the changes seen after IVB. Further studies are warranted in order to determine if there are any differences between IVB and IVR in this regard.