Intraoral Drug Delivery: Bridging the Gap Between Academic Research and Industrial Innovations

Abstract Intraoral delivery of active pharmaceutical ingredients (API) is an attractive approach to improve their local therapeutic efficacy or to enable their systemic delivery. It offers several advantages, such as high drug concentration at the intraoral target site and rapid access to the systemic circulation due to high vascularization of the oral cavity, bypassing first‐pass metabolism. However, several limitations need to be addressed, such as the relatively short residence time of formulations applied in the oral cavity due to salivation, swallowing reflex, and tongue movement, as well as poor membrane permeability of, in particular, hydrophilic drugs. Within this review, a comprehensive summary of the latest strategies and formulation approaches in the field of intraoral drug delivery is provided, focusing on those pursued by academia and industry to overcome those challenges. An overview is provided of excipients that are generally recognized as safe (GRAS) and utilized to enhance the efficacy of intraoral drug delivery systems, such as mucoadhesive materials, enzyme inhibitors, and permeation enhancers. Innovative pharmaceutical dosage forms are outlined, covering solid, semi‐solid, and liquid delivery systems as well as aerosols. Future trends, including self‐emulsifying systems, microneedles, and in situ bioprinting, are explored, presenting new opportunities for intraoral drug delivery.