C3 and age-related macular degeneration: The important role of the complement system in the etiopathogenesis of AMD has been also supported by recent multicenter studies assessing the efficacy of the intravitreal treatment with complement cascade inhibitors targeting complement proteins C3, C5, and CD59, injected either alone or in combination with vascular endothelial growth factor (VEGF) inhibitors, in patients with exudative AMD.