Intraocular Cytokines and Growth Factors in Neovascular Age-Related Macular Degeneration and the Effect of Therapy with Ranibizumab

Abstract

Purpose: : To investigate concentrations of growth factors and inflammatory cytokines in eyes with neovascular age-related macular degeneration (AMD) before and during therapy with intravitreal ranibizumab and to identify associations with disease activity.

Methods: : In a prospective clinical trial 28 eyes of patients with neovascular AMD were compared to 28 eyes of age-matched cataract patients as control. Ranibizumab was administered intravitreously once at baseline and re-treatments were given at monthly visits if OCT revealed macular edema or if vision loss had occurred. Aqueous humor samples were taken each time intravitreal interventions were performed. Follow-up was 12 months. Luminex multiplex assays were used for measurement of 29 different growth factors and cytokines.

Results: : A significantly increased expression of VEGF (p=0.033) and a significantly decreased expression of PDGF (p=0.038) was measured in the aqueous humor of eyes with neovascular AMD. Furthermore, a significant decrease of VEGF (p<0.001) was observed after intravitreal injection of ranibizumab along with significant changes in visual acuity and central retinal thickness (p=0.039 and p<0.001). During follow-up with a flexible regimen, a correlation was identified between increased VEGF levels and persistent or recurrent macular edema. Changes in PDGF levels were strongly associated with alterations in VEGF concentration.

Clinical Trial: : European clinical database EUDRACT-2006-005684-26

Keywords: choroid: neovascularization • aqueous • age-related macular degeneration