Factors Affecting Disease Stability After Intravitreal Brolucizumab Injection for Refractory Neovascular Age-Related Macular Degeneration

Abstract

Introduction The purpose of this study is to identify the factors affecting neovascular age-related macular degeneration (nAMD) disease stability after brolucizumab treatment. Methods We retrospectively analyzed the medical records of 31 patients (31 eyes) with recalcitrant nAMD who were switched to brolucizumab after conventional anti-vascular endothelial growth factor (VEGF) treatment. We divided patients into two groups by treatment extension (TE) period: group 1 with TE < 12 weeks ( N = 16) and group 2 with TE ≥ 12 weeks ( N = 15). We compared outcomes between the groups at 2, 4, 8, and 12 weeks, including morphological characteristics of choroidal neovascularization (CNV). Logistic regression analysis identified factors associated with TE ≥ 12 weeks. Results Group 2 had a significantly greater proportion of patients with dry macula (subretinal and intraretinal fluids absent) than group 1 (60 vs. 12.5%) at 2 weeks ( P < 0.05). Best-corrected visual acuity (BCVA) and subfoveal choroidal thickness (SFCT) did not differ significantly between groups at all timepoints. Central subfield retinal thickness (CST) was significantly lower in group 2 at 2 (237.1 vs. 280.8 μm; P < 0.05), 4 (224.0 vs. 262.9 μm; P < 0.05), and 8 weeks (216.8 vs. 331.1 μm; P < 0.05). Group 2 had less vessel area (0.63 vs. 1.27 mm 2 ; P < 0.05) and total vessel length (0.22 vs. 0.42 mm; P < 0.05). Choriocapillaris flow deficit (CCFd) was significantly lower in group 2 (42.7 vs. 48.2%; P < 0.05). Dry macula at 2 weeks (odds ratio [OR] = 8.3; P < 0.05) and a lower CCFd (OR = 0.73; P < 0.05) were associated with TE ≥ 12 weeks. Conclusions Early fluid-free status after switching to brolucizumab and choriocapillary function around CNV were prognostic factors for disease stability in nAMD refractory to anti-VEGF treatment.