Systemic bevacizumab (Avastin) therapy for neovascular age-related macular degeneration twelve-week results of an uncontrolled open-label clinical study

Abstract

Purpose: To evaluate the short-term safety of systemic bevacizumab (Avastin, Genentech, Inc., South San Francisco, CA) and its effects on visual acuity (VA) and subfoveal choroidal neovascularization (CNV) in patients with neovascular age-related macular degeneration (AMD).

Design: Open-label, single-center, uncontrolled clinical study.

Participants: Age-related macular degeneration patients with subfoveal CNV (N = 9) and best-corrected VA letter scores of 70 to 20 (approximate Snellen equivalent, 20/40-20/400).

Methods: Patients were treated at baseline with an infusion of bevacizumab (5 mg/kg), followed by 1 or 2 additional doses given at 2-week intervals. Safety assessments were performed at all visits. Ophthalmologic evaluations included protocol VA measurements and ocular examinations, along with optical coherence tomography (OCT) imaging, fluorescein angiography, and indocyanine green angiography.

Main outcome measurements: Safety assessments were performed, along with assessments of changes from baseline in VA scores, OCT measurements, and angiographic lesion characteristics.

Results: There were no serious ocular or systemic adverse events identified. By 6 weeks, the only adverse event identified was a mild elevation of systolic blood pressure (BP) (+12 mmHg; P = 0.035), and this elevation was controlled by either changing or initiating antihypertensive medication. By 12 weeks, the elevation of systolic BP was no longer significant (P = 0.51). In the study eyes, significant increases in VA were evident within 1 week of treatment, and by 12 weeks, the median and mean VA letter scores increased by 8 letters (P = 0.011) and 12 letters (P = 0.008), respectively. The median and mean central retinal thickness measurements decreased by 157 microm (P = 0.008) and 177 microm (P = 0.001), respectively. In the fellow eyes at 12 weeks, the median and mean VA letter scores increased by 27 letters (P = 0.018) and 16 letters (P = 0.012), and the median and mean central retinal thickness measurements decreased by 59 mum (P = 0.028) and 92 microm (P = 0.06). In all study eyes, angiography revealed a marked reduction or an absence of leakage from CNV.

Conclusion: Overall, bevacizumab therapy was well tolerated, with an improvement in VA, OCT, and angiographic outcomes. Although these preliminary results are promising, a randomized controlled clinical trial is necessary before concluding that systemic bevacizumab therapy is safe and effective for patients with neovascular AMD.