Ocular angiostatic agents

As angiogenesis is important to the developing eye, continued proliferation in the post-natal period will result in a host of ocular disorders, many of which will lead to blindness. Significant inroads to the impedance of aberrant vessel growth have been derived from numerous fields of study including oncology, wound healing and ophthalmology. Angiogenesis is a complex process involving a variety of steps including: elaboration of angiogenic factors, activation of receptor linked signalling pathways, altered gene expression resulting in modulation of the receptor/signalling pathway or to the production of extracellular proteinases that degrade the vascular endothelial cell (VEC) basement membrane and components of the extracellular matrix. Extracellular modifications are required for migration of activated VECs and subsequent differentiation into newly formed blood vessels. To all aspects of the angiogenic cascade, new drug candidates have been described and tested in a variety of ocular neovascularisation models. A number of these agents are currently in clinical phases of investigation for disorders in both the anterior and posterior segments of the eye.