Recent Progress on Topical Drug Therapy for Corneal Neovascularization

The cornea is a crucial refractive medium in the visual system, characterized by its avascular and transparent nature under physiological conditions. Pathological factors such as ocular trauma and inflammation can induce the formation of new capillaries from the limbal vascular network, leading to corneal neovascularization (CNV). With an associated blindness rate as high as 12%, CNV has become a significant challenge in ophthalmology. Current treatment strategies for CNV primarily include drug therapy such as anti-inflammatory and antiangiogenic agents, as well as surgical procedures like laser photocoagulation. These approaches are often limited by invasive procedures, suboptimal efficacy, and other constraints. Therefore, developing effective, safe, and convenient therapeutic options has become a critical research focus. Due to structural barriers of the ocular surface, the bioavailability of conventional eye drops is limited to ≈1%-5%, significantly restricting therapeutic efficacy. In recent years, researchers have been actively optimizing drug delivery systems using nanotechnology, hydrogels, and other advanced techniques to prolong ocular surface retention time, improve corneal penetration, and enhance drug release properties. This review summarizes recent advances in topical drug therapy for CNV, focusing on its pathogenesis, therapeutic agents, and delivery strategies, as well as approaches to enhance the bioavailability of topical treatments.