Intravitreal bevacizumab has initial clinical benefit lasting eight weeks in eyes with neovascular age-related macular degeneration

P William Conrad, David N Zacks, Mark W Johnson

Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, USA

Purpose: To determine whether the effect of a single initial intravitreal injection of bevacizumab for neovascular age-related macular degeneration (AMD) persists for 8 weeks.

Methods: We reviewed the records of 25 consecutive patients with neovascular AMD treated with intravitreal bevacizumab. Patients were included (n = 15) if follow up data were available from 4 and 8 week visits after a single initial injection. Additionally, optical coherence tomography (OCT) images were graded qualitatively in a masked fashion by a single reader.

Results: Baseline mean visual acuity was 20/200, improving to 20/125 at 4 weeks (p = 0.0153) and 20/100 at 8 weeks (p = 0.0027). Mean central retinal thickness was 316 ± 107 µm at baseline and decreased to 223 ± 70 µm and 206 ± 45 µm at 4 and 8 weeks post-injection, respectively (p = 0.0003 and 0.0005). By masked OCT grading, macular fluid was resolved in 10/15 (66.7%) and 11/15 (73.3%) eyes at 4 and 8 weeks, respectively, and 3/15 (20%) eyes had continued reduction in residual macular fluid between 4 and 8 weeks.

Conclusions: A single initial bevacizumab injection has persistent clinical benefit lasting 8 weeks in most eyes with neovascular AMD. Results of prospective randomized studies are needed before changes in treatment regimens can be recommended.

Keywords: age-related macular degeneration, bevacizumab, choroidal neovascular membrane, optical coherence tomography