Targeted Drug Delivery Systems for the Treatment of Glaucoma: Most Advanced Systems Review

Each year, new glaucoma drug delivery systems are developed. Due to the chronic nature of the disease, it requires the inconvenient daily administration of medications. As a result of their elution from the eye surface and penetration to the bloodstream through undesired permeation routes, the bioavailability of active compounds is low, and systemic side effects occur. Despite numerous publications on glaucoma drug carriers of controlled drug release kinetics, only part of them consider drug permeation routes and, thus, carriers' location, as an important factor affecting drug delivery. In this paper, we try to demonstrate the importance of the delivery proximal to glaucoma drug targets. The targeted delivery can significantly improve drug bioavailability, reduce side effects, and increase patients' compliance compared to both commercial and scientifically developed formulations that can spread over the eye surface or stay in contact with conjunctival sac. We present a selection of glaucoma drug carriers intended to be placed on cornea or injected into the aqueous humor and that have been made by advanced materials using hi-tech forming methods, allowing for effective and convenient sustained antiglaucoma drug delivery.