Brinzolamide-brimonidine Fixed Combination for Preventing IOP Elevation After Intravitreal Anti-VEGF Injections

Overview

This study aims to evaluate the effect of topical prophylaxis with brinzolamide-brimonidine fixed combination on short-term intraocular pressure (IOP) elevation after intravitreal injections of anti-vascular endothelial growth factors (anti-VEGF). Patients scheduled for treatment with intravitreal injections of anti-VEGF will be randomly divided into two groups. In control group no prophylactic medication will be used, whereas in case group one drop of brinzolamide-brimonidine fixed combination will be instilled two hours before the injection. IOP will be measured before the injection, 1 minute after the injection, 10 minutes and 30 minutes post-injection in all eyes. In case group, the pre-injection IOP will be measured prior to the administration of the fixed combination of brinzolamide-brimonidine. The iCare (IC200) tonometer will be used for IOP measurements at all time points.

The intravitreal anti-VEGF (ranibizumab, bevacizumab, pegaptanib and aflibercept) are commonly used in the treatment of diabetic macular edema, neovascular age-related macular degeneration and other pathologies characterized by retinal or choroidal neovascularization. Intravitreal injections οf anti-VEGF agents result in an immediate and transient increase in IOP, which returns to normal within a short period of time, typically within thirty minutes. Repeated intravitreal injections and prolonged treatments seem to be associated with sustained elevation of IOP, leading to the initiation of ocular hypotensive medication and glaucoma filtration surgery. A fixed-dose combination of brinzolamide 1%, a carbonic anhydrase inhibitor, and brimonidine 0,2%, an alpha 2 adrenergic receptor agonist, represents a safe and effective drug in glaucoma treatment and its ocular hypotensive effect has been demonstrated similar to or better than the unfixed combinations of its component drugs.