Update on clinical trials targeting vascular endothelial growth factor in cancer

The clinical trials of vascular endothelial growth factor (VEGF) inhibitors are discussed.

The recent approval of bevacizumab (a recombinant humanized monoclonal antibody to vascular endothelial growth factor) for the treatment of patients with metastatic colorectal cancer heralds a new era in cancer therapy as bevacizumab is the first dedicated antiangiogenic agent available for routine use. Many other agents designed to target VEGF are in development, including other antibodies targeting the receptor or ligand, soluble receptors, and small-molecule inhibitors of receptor tyrosine kinase function. While some agents are still in the preclinical stages of testing, clinical trials have been done or are ongoing with many VEGF inhibitors. Some of the clinical data are very encouraging, although the development of this class of agents has been hindered in some cases by the lack of dose limiting toxicity and the lack of an accurate understanding of the dose-response relationship. Future efforts will be aimed at elucidating the mechanisms underlying resistance and activity, and optimizing the use of these agents alone and in combination with other modalities in clinical practice. Establishing the relative merits of the different anti-VEGF strategies is another area of intense effort.

The current data on VEGF inhibitors are encouraging in regard to the treatment of cancer and should continue to be studied in relationship to other antiangiogenic agents.