Exosome-Mediated Drug Delivery Systems: Emerging Frontiers in Precision Medicine, Targeted Therapeutics, and Their Significance in Overcoming Current Drug Delivery Challenges

Exosome-mediated drug delivery systems have emerged as a promising platform for precision medicine, offering a natural and biocompatible means to deliver therapeutics with high specificity. Exosomes are nanoscale vesicles secreted by various cell types, such as mesenchymal stem cells, tumor cells, and immune cells, and are involved in intercellular communication. Due to their unique properties, such as the ability to cross biological barriers (e.g., the blood-brain barrier) and target specific tissues, exosomes hold great potential for overcoming current drug delivery challenges, including poor bioavailability, off-target effects, and toxicity. This review explores the biogenesis, composition, and functional characteristics of exosomes, focusing on their advantages as drug delivery vehicles. Key strategies for drug loading and surface engineering are discussed, including passive and active approaches, as well as the potential for targeting ligands to enhance therapeutic specificity. Furthermore, the applications of exosome-based systems in cancer therapy, neurological disorders, inflammatory diseases, and cardiovascular conditions are highlighted, illustrating their versatile therapeutic potential. Despite significant progress, several challenges remain, including issues related to exosome heterogeneity, standardization of isolation methods, and large-scale production. The review concludes with future perspectives on integrating artificial intelligence, developing exosome-mimetic systems, and advancing personalized exosome therapeutics for the ranostic applications.