Thymosin Beta 4: A Potential Novel Therapy for Neurotrophic Keratopathy, Dry Eye, and Ocular Surface Diseases

Chronic ocular surface diseases such as dry eye, blepharitis, and neurotrophic keratopathies represent a significant and a growing therapeutic challenge. The basis of this expanding prevalence is multifactorial and may due to issues such as an aging population, an increasing use of video display terminals, and increases in frequency of refractive surgeries. The growing incidence of diseases such as diabetes may also be a contributing factor. Current treatments for ocular surface disease include artificial tears, lubricants, tear duct plugs, steroids, antibiotics, cyclosporine, scleral lenses, and serum tears. Treatment choices depend on the type and severity of the disease, but in general positive outcomes are limited because many of these treatments do not fully address the underlying disease process or promote mechanisms that facilitate long-term wound repair. From minor corneal injuries to more severe inflammatory-mediated pathologies, clinicians need agents that promote corneal healing and reduce the inflammatory response to prevent visual disturbances and improve quality of life. A focus on treatments that reduce the inflammatory responses while accelerating corneal epithelial growth would represent a major step forward from current treatment options. Increasing evidence suggests that thymosin beta 4 (T beta 4), a naturally occurring polypeptide, can elicit this spectrum of therapeutic responses: a rapid corneal reepithelialization and a reduction in corneal inflammation. This chapter serves as a review of standard therapies as well as recent advancements in the development of newer therapies that includes the use of T beta 4 that is proving to be an exciting new agent for the management of ocular surface disease.