Current status and advances in esophageal drug delivery technology: influence of physiological, pathophysiological and pharmaceutical factors

Abstract

Diseases affecting the esophagus are common. However, targeted drug delivery to the esophagus is challenging due to the anatomy and physiology of this organ. Current pharmacological treatment for esophageal diseases predominantly relies on the off-label use of drugs in various dosage forms, including those for systemic drug delivery (e.g. oral tablets, sublingual tablets, and injections) and topical drug delivery (e.g. metered dose inhaler, viscous solution or suspension, and endoscopic injection into the esophagus). In general, systemic therapy has shown the most efficacy but requires the use of high drug doses to achieve effective concentrations in the esophagus, which increases the risk of adverse effects and toxicity. Topical drug delivery has enormous potential in improving the way we treat patients with acute and chronic esophageal diseases, especially those requiring drugs that have low therapeutic index and/or significant adverse effects to non-targeted organs and tissues. This review will address the physiological, pathophysiological, and pharmaceutical considerations influencing topical drug delivery in the esophagus. The main conventional (e.g. liquid formulations, orodispersible tablets, lozenges, pastilles, troches, chewing gum) and innovative (e.g. stent-based, film-based, nanoparticulate-based) drug delivery approaches will be comprehensively discussed, along with the developments to improve their effectiveness for topical esophageal drug delivery. The translational challenges and future clinical advances of this research will also be discussed.

Bio-Inspired Untethered Robot-Sensor Platform for Minimally Invasive Biomedical Sensing

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“…It is noteworthy that the viscosity of the experimental surface surpasses the typical viscosity of mucus within the human esophagus (130 cP). 45 These capabilities demonstrate the soft kirigami robot's snake-like adaptability to complex environments, including dry environments, wet environments, undulated topography, and surfaces with different slopes. The soft Kirigami robot also exhibits superior steering capability and deployability, with the ability to be steered in all directions and flipped upside down, as shown in Figure 6F,G.…”

Nanodrug delivery materials for digestive system diseases

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Chitosan Nanoparticles for Gastroesophageal Reflux Disease Treatment

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