Cutting-Edge Achievements of Inner Ear Drug Delivery Systems

The intricate physiological structure of the inner ear presents challenges for traditional medication treatment strategies, including systemic adverse responses, trouble penetrating the blood-labyrinth barrier, and low local cochlear concentration, resulting in poor therapeutic outcomes. An intriguing tactic that is extensively developed over decades is utilizing drug delivery systems to transport medication molecules to the inner ear. Herein, the challenges associated with inner ear delivery are discussed, cutting-edge achievements in inner ear drug delivery systems are emphasized, including nano-, micro-, and macrocarriers, and finally opportunities to leverage advanced technologies to improve existing drug delivery strategies are highlighted. Inner ear drug delivery systems can overcome the challenges faced by traditional administration strategies, particularly the inherent anatomical barriers and clearance through the Eustachian tube. This perspective focuses on reviewing representative results of inner ear drug delivery systems at the nano-, micro-, and macroscales, with a view to providing insights for further research.image (c) 2024 WILEY-VCH GmbH