Current formulation strategies to design novel carriers for targeted drug delivery and management of Infectious keratitis: A comprehensive review on the present state of the art

Infectious keratitis is a pernicious disease that affects the anterior segment of the eye and is one the leading causes of blindness worldwide. This disease may cause severe visual impairment or permanent vision damage if left untreated. No doubt there are many conventional drug delivery systems to treat ocular keratitis, yet it is the fifth leading cause of blindness globally. This is the result of the eye's complex anatomy and barrier system, which restricts the total ocular contact time of the conventional formulations resulting in under-dosing. The widely used traditional formulations to treat keratitis, like antibiotic eye drops and ointments, are rendered useless due to less ocular contact time and low therapeutic drug levels at the target ocular site. The main requirement of the present time is to develop novel drug delivery-backed stratagems to overcome the shortcomings of conventional formulations, which will reduce the morbidity associated with infectious keratitis and improve clinical outcomes. It is worth mentioning that there are documented incidents of Herpetic keratitis of the cornea followed by COVID-19 infection and vaccination. This paper is a rigorous review of all the novel drug delivery strategies to combat ocular keratitis. These future drug delivery strategies will pave the way for the present time researcher and formulation chemists to develop multi-dimensional novel formulations that are safe, patient-compliant, and surpass the ocular barriers to maintain therapeutic drug levels in ocular tissues.