Intravitreal bevacizumab (Avastin) for occult choroidal neovascularization in age-related macular degeneration

Background: The purpose of the study is to report data on short-term safety of intravitreal bevacizumab treatment and its effect on visual function, central retinal thickness, and angiographical changes of occult choroidal neovascularization due to age-related macular degeneration. Methods: A consecutive interventional case series of 30 patients with active subfoveal occult choroidal neovascularization secondary to age-related macular degeneration was followed after one intravitreal injection of 1.25 mg bevacizumab at baseline and subsequent injections following standardized criteria. At baseline and follow-up visits patients had visual acuity assessment, intraocular pressure measurement, fluorescein angiography, and optical coherence tomography imaging. Results: No serious ocular or systemic adverse events were identified. A significant increase of intraocular pressure or signs of retinal toxicity or endophthalmitis were not detected in any patient. Optical coherence tomography revealed significant decrease (p ≤ 0.001) in central retinal thickness after 1 week, 4 weeks, and 12 weeks, respectively. Fluorescein leakage decreased within 1 week and improvement was maintained at week 12 in the majority of patients. Visual acuity improved or remained stable in 29 of 30 patients; improvement of 3 or more lines was seen in 14 of 30 patients; one patients showed improvement of 6 lines. No patient had severe vision loss of 6 lines or more; moderate vision loss of 3 lines was seen in one patient. Re-injections of bevacizumab according to standard criteria were performed one to two times during the follow-up period of 12 weeks with a re-injection interval of 4 to 18 weeks (median 8 weeks). Conclusions: Short-term results suggest that intravitreal injection of bevacizumab is well tolerated and for the majority of patients with occult choroidal neovascularization in AMD results in improvement of visual acuity, decrease in central retina thickness, and reduction of angiographic leakage of the lesion. Bevacizumab as intravitreal treatment may provide a novel therapeutic option for selected patients with exudative AMD. Randomized prospective multicenter trials seem justified to further evaluate long term effects and impact of intravitreal bevacizumab on different subtypes of AMD compared to established therapies.