Recent perspectives on the delivery of biologics to back of the eye

Abstract

Introduction Biologics are generally macromolecules, large in size with poor stability in biological environments. Delivery of biologics to tissues at the back of the eye remains a challenge. To overcome these challenges and treat posterior ocular diseases, several novel approaches have been developed. Nanotechnology-based delivery systems, like drug encapsulation technology, macromolecule implants and gene delivery are under investigation. We provide an overview of emerging technologies for biologics delivery to back of the eye tissues. Moreover, new biologic drugs currently in clinical trials for ocular neovascular diseases have been discussed. Areas Covered Anatomy of the eye, posterior segment disease and diagnosis, barriers to biologic delivery, ocular pharmacokinetic, novel biologic delivery system Expert Opinion Anti-VEGF therapy represents a significant advance in developing biologics for the treatment of ocular neovascular diseases. Various strategies for biologic delivery to posterior ocular tissues are under development with some in early or late stages of clinical trials. Despite significant progress in the delivery of biologics, there is unmet need to develop sustained delivery of biologics with nearly zero-order release kinetics to the back of the eye tissues. In addition, elevated intraocular pressure associated with frequent intravitreal injections of macromolecules is another concern that needs to be addressed.

17β-Estradiol Delivered in Eye Drops: Evidence of Impact on Protein Networks and Associated Biological Processes in the Rat Retina through Quantitative Proteomics

“…Therefore, it is not surprising that crystallin-based cell survival strategies have been proposed to protect and rescue RGCs from degeneration associated with glaucomatous and other optic neuropathies [50]. However, therapeutic protein delivery to the retina faces many obstacles [66][67][68] compared to small molecule therapy such as E 2 delivered topically [20], which would induce the desired changes in protein expression.…”

Ocular delivery of proteins and peptides: Challenges and novel formulation approaches

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Dendrimers for ocular drug delivery

“…23 Posterior segment diseases such as macular degeneration and retinopathy cannot currently be treated with topical vehicles and require more invasive techniques such as direct injections or surgical interventions. 24, 25 …”