Conventional and Advanced Ocular Formulation and Delivery: A Mini Review

Objective: To review available ocular formulation and delivery for the treatment of eye diseases, and to discuss the advantages and disadvantages of the ophthalmic formulation and delivery due to the complexity anatomical of the eye.Data Sources: A literature search through Pub Med (1984 – December 2016) was performed using the key words: ocular barrier, posterior segment, anterior segment, disease of the eye, peptide delivery, ocular delivery, ophthalmic.Study Selection and Data Extraction: Articles in English identified from reviews, abstracts, and presentations on eye formulation and delivery were included.Conclusion: Effective treatment of ocular diseases has been difficult challenges due to the nature of the disease, the presence of the ocular barriers, and the unique structure of the eye. Within the last 2 decades, challenges in drug delivery have been partially met through modification of the ophthalmic formulations using viscosity enhancing polymers, hydrogels; through formulation of novel drugs approach using prodrugs, gene therapy and peptide delivery; and through making the drug particles smaller using nano-formulations techniques which all are aimed to increase the drug’s retention time in the eye, to have the least side effects, and to be minimally invasive. However, there are many more challenges that need to be addressed including: the application from the research bench top using rabbit or cadaver into patients’ specific diseases, decreasing the toxicities of the formulations, and making the ophthalmic formulations and deliveries safe, well-tolerated and cost efficient