Topical ophthalmic administration: Can a drug instilled onto the ocular surface exert an effect at the back of the eye?

Topical ophthalmic instillation is an appealing strategy to deliver drugs the back of eye treat retinal diseases such as neovascular age-related macular degeneration, diabetic retinopathy, vein occlusion, and glaucomatous optic neuropathy. It has several advantages being non-invasive user-friendly, e.g., allowing self-administration. However, main obstacle been how achieve therapeutic drug concentrations in retina due eye’s protective mechanisms, flows, barriers. Less than 4% instilled dose enters anterior chamber, much less expected reach posterior segment. crucial understand a drug’s topical pharmacokinetics humans one can extrapolate data from rabbits humans. In this review, available on vitreous studies conducted human patients have compiled, together with critical physiological factors be considered for route administration. Improvements design preclinical are suggested increase their translatability treatment patients. Finally, current status clinical trials formulations intended depicted. At present, no degeneration or other neurodegenerative illnesses reached market.