Age-related macular degeneration (AMD) is one of the leading causes of blindness in the United States, affecting approximately 11 million patients. AMD is caused primarily by an upregulation of vascular endothelial growth factor (VEGF). In recent years, aflibercept injections have been used to combat VEGF. However, this treatment requires frequent intravitreal injections, leading to low patient compliance and several adverse side effects including scarring, increased intraocular pressure, and retinal detachment. Polymeric nanoparticles have demonstrated the ability to deliver a sustained release of drug, thereby reducing the necessary injection frequency. Aflibercept (AFL) was encapsulated in poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs) via double emulsion diffusion. Scanning electron microscopy showed the NPs were spherical and dynamic light scattering demonstrated that they were uniformly distributed (PDI < 1). The encapsulation efficiency and drug loading were 75.76% and 7.76% respectively. In vitro release studies showed a sustained release of drug; 75% of drug was released by the NPs in seven days compared to the full payload released in 24 h by the AFL solution. Future ocular in vivo studies are needed to confirm the biological effects of the NPs. Preliminary studies of the proposed aflibercept NPs demonstrated high encapsulation efficiency, a sustained drug release profile, and ideal physical characteristics for AMD treatment. This drug delivery system is an excellent candidate for further characterization using an ocular neovascularization in vivo model.

Micro-(MPs) and nanoparticles (NPs) have been recently studied for their application in ophthalmic drug delivery. These drug delivery systems are able to circumvent the ocular barriers that currently limit the efficacy of conventional treatments, as well as provide a more sustained release of drug, reducing the frequency of administration and increasing patient compliance. This review summarizes the recent trends in ophthalmic research from conventional treatment to the utilization of MPs and NPs as drug carriers.

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Background: The current treatment of ocular neovascularization requires frequent intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents that cause severe side effects. Objective: The purpose of this study is to prepare and characterize a novel nanoscale delivery system of apatinib for ocular neovascularization. </P><P> Methods: The optimized formulation showed a particle size of 135.04 nm, polydispersity index (PDI) of 0.28 &#177; 0.07, encapsulation efficiency (EE) of 65.92%, zeta potential (ZP) of -23.70 &#177; 8.69 mV, and pH of 6.49 &#177; 0.20. In vitro release was carried out to demonstrate a 3.13-fold increase in the sustainability of apatinib-loaded nanoparticles versus free apatinib solution. </P><P> Result: Cell viability and VEGFA and VEGFR2 expression were analyzed in animal retinal pigment epithelial (ARPE-19) cells. The results confirmed the hypothesis that apatinib nanoparticles decreased toxicity (1.36 &#177; 0.74 fold) and efficient VEGF inhibition (3.51 &#177; 0.02 fold) via VEGFR2 mediation.