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Ocular drug delivery is one of the most fascinating and challenging tasks facing pharmaceutical researchers. Improving drug ocular residence time and/or penetration is complex. Microparticles (MP) provide interesting opportunities to increase ocular bioavailability of drugs and patient compliance brought about by decreased frequency of dosing. However, sustained-release microsphere formulation would fail to accomplish the task of long-lasting drug release unless microspheres remained for a prolonged period at the site of action. Some strategies have been assessed to retain MP at the target site. Among them, improving bioadhesion properties is possibly the one that offers the best technical features to date. In this review, we present the latest scientific communications in the field of MP development and coating to increase bioavailability when MP are destined for ocular treatment. All of these are more or less useful tools that must be considered as an important part of the development process for ocular medication optimization., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Dexamethasone is one of the most prescribed glucocorticoids. It is effective and safe in the treatment of a wide variety of ocular conditions, including anterior and posterior segment inflammation. However, its half-life in the vitreous humor is very short, which means that it typically requires frequent administrations, thus reducing patient adherence and causing therapeutic failure. Innovative dexamethasone delivery systems have been designed in an attempt to achieve sustained release and targeting. The FDA has approved dexamethasone implants for the treatment of macular edema secondary to retinal vein occlusion and posterior segment noninfectious uveitis. Lenses, micro- and nanoparticles, liposomes, micelles and dendrimers are also proving to be adequate systems for maintaining optimal dexamethasone levels in the site of action. Pharmaceutical technology is turning a classical drug, dexamethasone, into a fashionable medicine., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Dendrimers have called the attention of scientists in the area of drug and gene delivery over the last two decades for their versatility, complexity and multibranching properties. Some strategies for optimizing drug pharmacokinetics and site-specific targeting using dendrimers have been proposed. Among them, those related to treating and managing ocular diseases are of special interest. Ocular therapies suffer from significant disadvantages, including frequent administration, poor penetration and/or rapid elimination. This review provides an overview of the recent and promising progress in the dendrimers field, focusing on both the anterior and posterior segments of the eye ocular targets, the use of dendrimers as a strategy for overcoming obstacles to the traditional treatment of ocular diseases and an outlook on future directions. Finally, a first approach to ocular safety with dendrimers is intended that accounts for the state-of-the-art science to date., (Copyright © 2016 Elsevier B.V. All rights reserved.)