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This article reviews the field of oral uptake of nanoparticles across the gastrointestinal epithelium for the period 2006–2016. Analysis is conducted from the viewpoint of i) M-cell genetics and model development, ii) drug targeting to Peyer's patches and M-cells, and iii) physicochemical interactions of nanoparticles in the intestinal milieu. In light of these recent developments, regulatory considerations in the development of orally-absorbable nanoparticle drug products are discussed and focused on Module 3.2.P sub-sections of the Common Technical Document. Particular attention is paid to novel excipients, ligands and the non-standard method of manufacture. The novelty of this drug delivery system demands not only a multi-disciplinary scientific and regulatory approach but also a risk-adjusted consideration for a system defined by both processes and specifications. Given the current state of scientific development in the field it is suggested (in the author's personal opinion) that the design of nanoparticulate drug delivery systems should be kept as simple as possible (from a regulatory and manufacturing perspective) and to target the entire gastrointestinal epithelium. [ABSTRACT FROM AUTHOR]

Nasal vaccination is a promising alternative to classical parental vaccination, as it is non-invasive and, in principle, capable of eliciting strong systemic and local immune responses. However, the protective efficacy of nasally administered antigens is often impaired because of delivery problems: free antigens are readily cleared from the nasal cavity, poorly absorbed by nasal epithelial cells and generally have low intrinsic immunogenicity. In this review paper, we describe the main physiological hurdles to nasal vaccine delivery, survey the progress made in technological approaches to overcome these hurdles and discuss emerging opportunities for improving nasal vaccines. According to current insights, encapsulation of the antigen into bioadhesive (nano)particles is a promising approach towards successful nasal vaccine delivery. These antigen-loaded particles can be tailor made by supplying them with targeting ligands, adjuvants or endosomal escape mediators to form the desired vaccine that provides long-lasting protective immunity. [ABSTRACT FROM AUTHOR]

Although polymeric nanoparticles/microparticles are well established for the mucosal administration of conventional drugs, they have not yet been developed commercially for vaccine delivery. The limitation of the mucosal (particularly oral) route of delivery, including low pH, gastric enzymes, rapid transit and poor absorption of large molecules, has made mucosal vaccine delivery challenging. Nevertheless, several polymeric delivery systems for mucosal vaccine delivery are currently being evaluated. The polymer-based approaches are designed to protect the antigen in the gut, to target the antigen to the gut-associated lymphoid tissue or to increase the residence time of the antigen in the gut through bioadhesion. M-cell targeting is a potential approach for mucosal vaccine delivery, which can be achieved using M-cell-specific lectins, microbial adhesins or immunoglobulins. While many hurdles must be overcome before targeted mucosal vaccine delivery becomes a practical reality, this is a potential area of research that has important implications for future vaccine development. This review comprises various aspects that could be decisive in the development of polymer based mucosal vaccine delivery systems. [ABSTRACT FROM AUTHOR]