Advancements in Nanodrug Delivery Systems as Controlled-Release Systems for Glaucoma Therapy: An Inspirational Step Toward Translation from Research to Clinic

Glaucoma is a collection of disorders that result in permanent vision loss and is characterized by a gradual decline in retinal ganglion cells. While it may not always be high, intraocular pressure (IOP) is the sole risk factor that can be modified according to extensive clinical research. Glaucoma remains the leading cause of irreversible blindness, yet early treatment lowering intraocular pressure is effective in slowing the rate of visual deterioration. Issues like poor absorption, low bioavailability, and short drug resistance time have thus made the management of glaucoma challenging when using conventional ophthalmic drugs. Thus, extensive research has been conducted to explore specific nanodrug delivery systems from various nanocarriers such as nanoparticles, micelles, liposomes and nanofibers, with a focus on systems that have achieved drug release for more than 12 h. These carriers have demonstrated substantial improvements in a lot of the evaluated aspects: enhancing ocular barrier-crossing capabilities, improving bioavailability, prolonging drug release, targeting active tissues of interest, and reducing IOP. This review covers recent developments in nanocarrier ocular delivery systems regarding the management of glaucoma. In this study, the advantages and disadvantages of each system were evaluated and their potential for advancing translation from research to clinic were assessed.