Recent trends in drug-delivery systems for the treatment of diabetic retinopathy and associated fibrosis

Diabetic retinopathy is a frequent microvascular complication of diabetes and a major cause of visual impairment. In advanced stages, the abnormal neovascularization can lead to fibrosis and subsequent tractional retinal detachment and blindness. The low bioavailability of the drugs at the target site imposed by the anatomic and physiologic barriers within the eye, requires long term treatments with frequent injections that often compromise patient's compliance and increase the risk of developing more complications. In recent years, much effort has been put towards the development of new drug delivery platforms aiming to enhance their permeation, to prolong their retention time at the target site and to provide a sustained release with reduced toxicity and improved efficacy. This review provides an overview of the etiology and pathophysiology of diabetic retinopathy and current treatments. It addresses the specific challenges associated to the different ocular delivery routes and provides a critical review of the most recent developments made in the drug delivery field. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

Diabetic retinopathy is a common complication of diabetes, with challenges in treatment due to the low bioavailability of drugs at the target site in the eye, requiring long-term and frequent injections. Efforts have been made in recent years to develop new drug delivery platforms to enhance permeation, prolong retention time, and provide sustained release to reduce toxicity and improve efficacy.