Sustained Drug Delivery Systems for Age-Related Macular Degeneration: Advancements, Challenges, and Future Perspectives.

Age-related macular degeneration (AMD) is a leading cause of vision loss among the elderly and remains a major public health challenge due to its chronic progression and high recurrence rate. Current standard treatment relies heavily on repeated intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents, which impose significant burdens on patients and healthcare systems. In recent years, sustained-release drug delivery systems (SR-DDS) have emerged as promising alternatives to overcome the limitations of frequent injections and to improve therapeutic outcomes in AMD.This chapter explores the rationale, mechanisms, and current advancements in hydrogel-based platforms and implantable devices designed for the long-term delivery of anti-VEGF agents. We provide a comparative analysis of these two delivery modalities, focusing on their materials, biocompatibility, release kinetics, clinical utility, and translational potential. Furthermore, we discuss the critical role of SR-DDS in supporting personalized medicine through patient-specific dosing strategies and their ability to maintain therapeutic drug levels with minimal invasiveness.Challenges in the development and regulatory approval of SR-DDS, including manufacturing complexity, long-term safety, and economic viability, are also addressed. Finally, we highlight emerging trends in biomaterials science, precision engineering, and combination therapy strategies that may shape the next generation of drug delivery platforms for AMD.Together, these insights underscore the transformative potential of SR-DDS in redefining the clinical management of AMD by offering sustained, localized, and patient-tailored therapeutic delivery.