Biodegradable Contact Lenses for Targeted Ocular Drug Delivery: Recent Advances, Clinical Applications, and Translational Perspectives

Abstract

Ocular drug delivery presents a persistent clinical challenge due to the protective anatomical structure of the eye, physiological barriers such as reflex blinking, and continuous tear fluid turnover. These factors significantly limit the bioavailability of topically applied medications, reducing the therapeutic effectiveness of conventional formulations, such as eye drops, ointments, and suspensions, particularly in the management of chronic ocular disorders, including dry eye syndrome, diabetic retinopathy, and age-related macular degeneration. Drug-eluting contact lenses (DECLs) offer a promising alternative, enabling sustained, localized, and controlled drug release directly at the ocular surface. While several reviews have addressed contact lenses as drug delivery platforms, this work provides a distinct perspective by focusing specifically on biodegradable polymer-based systems. Emphasis is placed on recent advances in the design and fabrication of DECLs using natural and synthetic biodegradable polymers, which offer superior biocompatibility, customizable degradation kinetics, and the capacity for programmable drug release. This review discusses the selection criteria for polymer matrices, strategies for drug incorporation, and key factors influencing release profiles. Moreover, this study highlights innovative methodologies and therapeutic approaches that differentiate it from the existing literature, providing a timely and comprehensive resource for researchers developing next-generation polymeric ocular drug delivery systems.

Keywords: biodegradable polymers; drug-eluting contact lenses (DECLs); ophthalmic biomaterials; sustained drug release.

Figure 1

Cross-sectional diagram of the human eye showing major anatomical regions involved in ocular pharmacokinetics.

Figure 2

Key barriers to effective ocular drug delivery.

Figure 3

Classification of contact lenses based on material, usage duration, and application.

Figure 4

Categorization of controlled ocular drug release mechanisms.

Figure 5

Representative polymer-based drug delivery systems for ocular administration at the macro- and nanoscale levels.

Figure 6

Key challenges and opportunities for DECLs.