Aqueous vascular endothelial growth factor and aflibercept concentrations after bimonthly intravitreal injections of aflibercept for age-related macular degeneration.

Abstract

Clinical evidence supports the efficacy of bimonthly aflibercept injection for age-related macular degeneration. The study aimed to evaluate aqueous vascular endothelial growth factor and aflibercept concentrations and the efficacy of bimonthly aflibercept in patients with age-related macular degeneration. This study is a prospective, interventional case series. Enrolled were 35 eyes with exudative age-related macular degeneration from 35 patients. Patients received three bimonthly intravitreal aflibercept without loading doses. We collected the aqueous humor just before each injection, measured vascular endothelial growth factor and aflibercept concentrations by enzyme-linked immunosorbent assay and measured best-corrected visual acuity and central retinal subfield thickness before and after the injections. Aqueous vascular endothelial growth factor and aflibercept concentrations were measured. The vascular endothelial growth factor concentration was 135.4±60.5pg/mL (mean±standard deviation, range 60.6-323.4) at baseline and below the lowest detectable limit in all eyes at month 2 and in 32 eyes at month 4 (P<0.001 [month 2] and P<0.001 [month 4]). The mean aflibercept concentration was 20.3ng/mL at month 2 and 28.0ng/mL at month 4. The mean logarithm of the minimum angle of resolution visual acuity improved from 0.50±0.36 at baseline to 0.36±0.40 at month 6 (P<0.001). The mean central retinal subfield thickness decreased from 353±100μm at baseline to 236±45μm at month 6 (P<0.001). Bimonthly aflibercept injections without loading doses may be considered a treatment option for age-related macular degeneration.