Off-Label Intravitreal Eculizumab for Geographic Atrophy: Report of the First Two Cases

Purpose: To report the feasibility and short-term safety of off-label intravitreal eculizumab as a complement-inhibition strategy for geographic atrophy (GA) secondary to age-related macular degeneration (AMD), based on two clinical cases. Case Reports: Two pseudophakic patients with progressive bilateral visual decline presented with GA and drusen in both eyes. Because this represents a novel, off-label therapeutic approach, intravitreal eculizumab was administered first in the worse-seeing eye in both cases, which also exhibited more advanced atrophic involvement. The treatment was selected as a potentially more accessible alternative to pegcetacoplan or avacincaptad pegol, which remain unavailable in Brazil. At one-month follow-up, no ocular toxicity was observed. Visual acuity remained stable in both patients; in Case 1, BCVA improved from 20/400 to 20/200, while Case 2 maintained baseline acuity. Full-field electroretinography demonstrated preserved responses without reduction in B-wave amplitude, and multifocal electroretinography showed stable response densities with no amplitude loss. After functional assessment, structural multimodal imaging also showed no evidence of toxicity. Optical coherence tomography (OCT) revealed stable GA-related outer retinal atrophy without inner retinal changes, intra- or subretinal fluid, or any signs of acute retinal injury. Fundus autofluorescence and OCT angiography remained unchanged, with no findings of ocular inflammation, vascular compromise, or early acceleration of GA progression. Conclusions: Intravitreal eculizumab was feasible and demonstrated short-term safety in these two cases, with preserved visual function and no electrophysiological or structural evidence of toxicity. While biologically plausible as a C5-inhibition strategy, its therapeutic benefit remains unproven. Larger, controlled studies with extended follow-up are required to clarify long-term safety and efficacy in geographic atrophy.