Recent Strategies for Ocular Drug Delivery: Promises and Challenges

Abstract

Ocular diseases include various anterior and posterior segment diseases. Due to the unique anatomy and physiology of the eye, efficient ocular drug delivery is a great challenge to researchers. The emerging nanoscience is playing an important role in the development of novel strategies for ocular disease management. Various active molecules have been designed to associate with nanocarriers to overcome ocular barriers and interact with certain ocular tissues. In this chapter, highlights will be made on barrier to intraocular delivery, general pathways for ocular absorption, and factors affecting intraocular bioavailability. The recent attempts of nanotechnology for treating anterior and posterior ocular diseases will be explored. This will include nanomicelles, nanoparticles, nanosuspensions, vesicular systems, in situ gel, dendrimers, contact lenses, implants, microneedles, and cell-based delivery systems. In addition, gene-based ocular delivery systems will be discussed. In this chapter, we will also provide a comprehensive overview of drug-device combinations used for ocular diseases such as glaucoma, dry eye disease, infections, and inflammations. Furthermore, drug delivery devices for ocular surgeries are discussed. Finally, challenges and future prospective of ocular delivery systems will be explored.