Vascular disruption represents a new approach to a validated therapeutic strategy: depriving tumors (and, in the case of eye disease, pathologic neovascular lesions) of vital blood supply.

In solid tumors, vascular disrupting agents, such as ZYBRESTAT and OXi4503, rapidly disrupt the existing tumor vasculature, working from within the tumor to reduce blood flow, and depriving the tumor of critically needed oxygen and nutrients, thereby resulting in rapid and extensive tumor cell death. This disruption of the preexisting blood vessels contrasts with the action of anti-angiogenic therapies, which are designed to prevent VEGF-driven new blood vessel formation, mostly occurring at the outside of tumors.