The Impact of R-801 Nanoparticles as a Long Acting Topical Glaucoma Therapy.

Primary open angle glaucoma (POAG) is the most common glaucoma type worldwide. The most significant risk factor of this type of glaucoma is the increased intraocular pressure (IOP) that may result in optic nerve damage and gradual but complete loss of vision. Reduction of IOP is the most important measure that should be taken into consideration during selection of glaucoma therapy. Several IOP-lowering medications are available in the drug market. Unfortunately, most of them associated with severe local and/or systemic adverse effects, short duration of action and poor patient compliance. In the current research we strive to develop a long acting, once daily, nanoparticle (NP)-based, ocular formulation loaded with R-801 (a newly discovered drug). Our NPs were prepared from carefully selected bioadhesive and biocompatible materials using double emulsification solvent diffusion method. This method of preparation was selected to obtain the highest encapsulation efficiency for our water-soluble drug and the smallest particle size for our NPs. Also, the NPs were incorporated in biocompatible and bioadhesive vehicles to achieve the required safety, biocompatibility and prolonged corneal contact time. Our formulations were subjected to various in vitro and in vivo evaluations that demonstrated their safety and ability to sustain the drug release, prolong corneal contact time, lower IOP in different animal models, and maintain the IOP at almost constant low value through the day without any fluctuation upon long-term daily application.