Intravitreal injection of 2.5 mg versus 1.25 mg bevacizumab (Avastin) for treatment of CNV associated with AMD

Abstract

Purpose: To compare the safety and efficacy of intravitreal injections of 1.25 and 2.5 mg bevacizumab for treatment of choroidal neovascularization associated with age-related macular degeneration.

Methods: In this prospective, randomized, comparative clinical trial, 86 patients with active choroidal neovascularization associated with age-related macular degeneration were studied. Baseline best-corrected visual acuity in the study eye was from 20/40 to 20/2000. Patients were randomly assigned to receive intravitreal injections of 2.5 (39 patients) or 1.25 mg (47 patients) of intravitreal bevacizumab. Best-corrected visual acuity measurement and clinical ocular examination were performed at 1 week, 1 month and then monthly for 5 months. Fluorescein angiography and optical coherence tomography were performed at 1 month and 3 months after each injection.

Results: The mean change in best-corrected visual acuity was -0.06 +/- 0.3 logMAR in 1.25 mg and -0.07 +/- 0.34 in 2.5 mg groups in 3 months (P = 0.9) and -0.06 +/- 0.27 logMAR in 1.25 mg and -0.09 +/- 0.28 in 2.5 mg groups in 5 months (P = 0.6). There was no significant difference in visual acuity between the two groups at any time point during the study. The mean change in foveal thickness was -49 +/- 36 micro in 1.25 mg and -65 +/- 31 micro in 2.5 mg group (P = 0.6). In 2.5 mg group, three cases of vitreous reaction and one case of massive subretinal hemorrhage were observed.

Conclusion: Intravitreal injection of 2.5 mg bevacizumab has the same efficacy as 1.25 mg, but may be associated with a higher rate of adverse events.