Engineering nanoparticles to overcome the mucus barrier for drug delivery: Design, evaluation and state-of-the-art

: Chitosan, a natural biodegradable polymer obtained from deacetylation of chitin, has been used as an approbative macromolecule for the development of various novel drug delivery systems. It is one of the most favorable biodegradable carriers for nanoparticulate drug delivery due to its intrinsic properties, such as biocompatibility, biodegradability, non-toxicity, availability of free reactive amino groups, and ease of chemical modification into different active derivatives. Furthermore, interesting physical properties (film-forming, gelling and thickening) make it a suitable candidate for formulations, such as films, microcapsules, beads, nanoparticles, nanofibres, nanogel and so on. Researchers have reported that chitosan nanoparticles act as a promising vehicle for herbal actives as they provide a superior alternative to traditional carriers and improve pharmaceutical efficiency. As no review of chitosan nanoparticles encapsulating herbal extracts and bioactives has been published till date, a maiden effort has been made to collate and review the use of chitosan nanoparticles for the entrapment of phytoconstituents to yield stable, efficient and safe drug delivery systems. Additionally, the paper presents a comprehensive account of the state-of the-art in fabricating herbal chitosan nanoparticles and their current pharmacological status. A list of patents on chitosan nanoparticles of herbal actives has also been included. This review is intended to serve as a didactic discourse for the formulation scientists endeavoring to develop advanced delivery systems for herbal actives.

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The role of KPI-121 0.25% in the treatment of dry eye disease: penetrating the mucus barrier to treat periodic flares

Therapeutic Advances in Ophthalmology ◽

10.1177/25158414211012797 ◽

2021 ◽

Vol 13 ◽

pp. 251584142110127

Author(s):

Preeya K. Gupta ◽

Nandini Venkateswaran

Keyword(s):

Drug Delivery ◽

Dry Eye ◽

Ocular Surface ◽

Dry Eye Disease ◽

Eye Disease ◽

Eye Drops ◽

Short Term ◽

Short Term Treatment ◽

Loteprednol Etabonate ◽

Mucus Barrier

The tear film, which includes mucins that adhere to foreign particles, rapidly clears allergens and pathogens from the ocular surface, protecting the underlying tissues. However, the tear film’s ability to efficiently remove foreign particles during blinking can also pose challenges for topical drug delivery, as traditional eye drops (solutions and suspensions) are cleared from the ocular surface before the drug can penetrate into the conjunctival and corneal epithelium. In the past 15 years, there has been an increase in the development of nanoparticles with specialized coatings that have reduced affinity to mucins and are small enough in size to pass through the mucus barrier. These mucus-penetrating particles (MPPs) have been shown to efficiently penetrate the mucus barrier and reach the ocular surface tissues. Dry eye disease (DED) is a common inflammatory ocular surface disorder that often presents with periodic flares (exacerbations). However, currently approved immunomodulatory treatments for DED are intended for long-term use. Thus, there is a need for effective short-term treatments that can address intermittent flares of DED. Loteprednol etabonate, an ocular corticosteroid, was engineered to break down rapidly after administration to the ocular surface tissues and thereby reduce risks associated with other topical steroids. KPI-121 is an ophthalmic suspension that uses the MPP technology to deliver loteprednol etabonate more efficiently to the ocular tissues, achieving in animal models a 3.6-fold greater penetration of loteprednol etabonate to the cornea than traditional loteprednol etabonate ophthalmic suspensions. In clinical trials, short-term treatment with KPI-121 0.25% significantly reduced signs and symptoms of DED compared with its vehicle (placebo). Recently approved KPI-121 0.25%, with its novel drug delivery design and ease of use, has the potential to effectively treat periodic flares of DED experienced by many patients.

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