Bevacizumab in the treatment of non-small-cell lung cancer

Lung cancer is the leading cause of cancer death in the United States. The majority of patients present with advanced disease, and treatment with standard cytotoxic chemotherapy improves survival and quality of life in patients with a preserved functional status. However, the prognosis is poor with the majority of patients dying in less than a year. Treatment with standard cytotoxic chemotherapy has reached a therapeutic plateau, and new therapeutic approaches have investigated therapies that target the specific molecular pathways involved in carcinogenesis and angiogenesis. The most promising strategy for inhibiting angiogenesis involves agents that either target the proangiogenesis growth factor, vascular endothelial growth factor A (VEGF) by preventing binding to the receptor or inhibiting the downstream signaling of the vascular endothelial growth factor receptor. The only therapeutic agent approved for the treatment of lung cancer is bevacizumab, a monoclonal antibody that binds to VEGF. A recent phase III trial revealed a statistically significant improvement in response rate, progression free and overall survival with combination of bevacizumab with chemotherapy over chemotherapy alone. Attempts to identify surrogate markers of antiangiogenesis activity are currently ongoing, and may assist in the selection of patients for antiangiogenesis therapy and the development of this class of agents.