Bevacizumab in age-related macular degeneration: a randomized controlled trial on the effect of on-demand therapy every 4 or 8 weeks
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Updated: Feb 3, 2026

Regenerative Therapy by Suprachoroidal Cell Autograft in Dry Age-related Macular Degeneration: Preliminary In Vivo Report
Published on: February 12, 2018
Sankha Amarakoon1,2, José P Martinez-Ciriano1, L Ingeborgh van den Born1
1Rotterdam Eye Hospital, Rotterdam, the Netherlands.
Purpose:
Intravitreal anti-vascular endothelial growth factor (VEGF) injections are an effective treatment for neovascular age-related macular degeneration (nARMD). Bevacizumab appears to be a cost-effective off-label anti-VEGF alternative to ranibizumab, but an optimal injection schedule has not yet been determined. In this study, we investigate whether on-demand bevacizumab treatment every 8 weeks is non-inferior to on-demand bevacizumab every 4 weeks in treating nARMD.
Methods:
A total of 120 nARMD patients were randomly assigned to an on-demand regimen of intravitreal bevacizumab (IVB) every 4 (n = 60) or 8 weeks (n = 60). The primary outcome was visual acuity (VA) change after 1 year of treatment.
Results:
Visual acuity (VA) improved between baseline and 1 year in both treatment groups. The mean change in the VA score at 1 year was not significantly different between bevacizumab administration on-demand every 4 weeks [5.6 ± 10.2 Early Treatment Diabetic Retinopathy Study (ETDRS) letter] or 8 weeks (4.6 ± 12.0 ETDRS letters). A reduction in the central retinal thickness was observed in both groups. At 1 year, the mean decrease in central foveal thickness ranged from 61 ± 90 μm in the 4-week group to 91 ± 83 μm in the 8-week group (p = 0.07). The mean number of IVB treatments during the study period was 8.7 ± 2.3 in the 4-week group and 5.9 ± 1.0 in the 8-week group.
Conclusion:
At 1 year, bevacizumab administration on-demand every 8 weeks was non-inferior to administration every 4 weeks. The results strongly suggest that bevacizumab acts longer than 4 weeks in ARMD, reducing the burden of injections for patients.
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