Ranibizumab for the Treatment of Macular Edema Associated With Perfused Central Retinal Vein Occlusions

Abstract

Purpose:: Vascular endothelial growth factor A (VEGF-A) increases retinal vascular permeability and may play a role in the development of macular edema. Ranibizumab (Lucentis^TM) is a humanized antigen-binding antibody fragment (Fab) that targets all VEGF-A isoforms and their biologically active degradation products. This study assesses the biologic effect, change in visual acuity, and safety of intravitreal (ITV) ranibizumab in patients with macular edema associated with perfused central retinal vein occlusions (CRVO).

Methods:: Ten patients with clinical, angiographic, and optical coherence tomography (OCT) evidence of macular edema associated with perfused CRVO are enrolled in this ongoing prospective, open-label study. Patients received 3 monthly ITV ranibizumab injections (0.3 or 0.5 mg) and will be re-treated over the ensuing 9 months as needed. The primary efficacy endpoint is the percentage of patients gaining at least 15 letters of best-corrected ETDRS visual acuity (BCVA) at 4 m from baseline to 6 and 12 months. The secondary endpoints included the change in BCVA from baseline to each study visit, the change in central retinal thickness measured with OCT at each study visit, the rates of progression to ischemic CRVO, and the incidence and severity of adverse events.

Results:: Prior to study enrollment, the mean duration of CRVO symptoms was 20.7 weeks (range, 6-52 weeks). At 1 month, ranibizumab treatment resulted in stable vision (a loss of <0 letters) in 100% of patients (n=10). BCVA improved by a mean of 9 ± 8 letters, and central retinal thickness decreased by a mean of 292.1 ± 167.2 µm compared with baseline. At 3 months, ranibizumab treatment resulted in stable vision in 100% of patients (n=6). Mean improvement in BCVA was 12.6 ± 14.9 letters, and central retinal thickness decreased by a mean of 367.7 ± 111.8 µm compared with baseline. So far, no serious ocular or systemic adverse events have been reported.

Conclusions:: In this small series, ranibizumab was well tolerated and appeared to reduce macular edema and improve, at least temporarily, BCVA in patients with macular edema associated with a perfused CRVO.

Clinical Trial:: www.clinicaltrials.gov Registered 11/29/06; number pending

Keywords: vascular occlusion/vascular occlusive disease • injection • retina