Abstract
Abstract: :
Purpose: Vascular endothelial growth factor (VEGF) is implicated as one of the major angiogenic factors responsible for choroidal neovascularization (CNV) in AMD. Recent clinical studies using intraocular anti–VEGF therapies for CNV in AMD have shown promising results. The SANA Study uses a systemic anti–VEGF humanized monoclonal antibody known as bevacizumab (Avastin®, Genentech Inc.) for the treatment of neovascular AMD. We proposed that systemic bevacizumab might improve visual acuity outcomes by leaking from active CNV, binding extracellular VEGF in the macula, and inhibiting the increased vascular permeability and growth of CNV attributed to VEGF. This off–label use of bevacizumab was possible once the FDA approved bevacizumab for the treatment of patients with metastatic colorectal cancer. Methods: This open–label, uncontrolled clinical study enrolled AMD patients with subfoveal CNV, a central retinal thickness of at least 300 microns, and visual acuity from 20/40 to 20/400. They were treated initially with 2 or 3 infusions of bevacizumab (5mg/kg) at 2 week intervals. Patients were examined every week for the first 6 weeks, every 2 weeks for the next 6 weeks, and every 4 weeks thereafter. At baseline and at each follow–up visit, patients underwent a medical review, ETDRS visual acuity (VA) assessment, ophthalmologic examination, and ocular imaging. Results: Of the 15 patients enrolled in the study, the first 9 patients have been followed for at least 3 months, and these patients received only 2 or 3 infusions of bevacizumab during this time. By 3 months, the median and mean visual acuity letter scores from the Study Eyes of these first 9 patients increased by 8 letters (p=0.011) and 12 letters (p=0.008), respectively. Significant visual acuity improvements were evident 1 week after the first dose. In the 9 Fellow Eyes, CNV was diagnosed in 8 eyes at baseline. Median and mean VA increased by 27 letters (p=0.018) and 16 letters (p=0.012), respectively. No serious adverse events were identified. Conclusions: Bevacizumab therapy resulted in stable or improved visual acuity in all eyes with subfoveal CNV after 3 months. The treatment appeared to be well tolerated. Follow–up is ongoing to determine the durability of these favorable visual acuity outcomes.
Keywords: choroid: neovascularization • age-related macular degeneration • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled