Antibodies to vascular endothelial growth factor in non-small cell lung cancer

Angiogenesis, formation of new vasculature, is critical to cancer growth. Agents that block angiogenesis, in particular bevacizumab, a monoclonal antibody that binds vascular endothelial growth factor, the key ligand in angiogenesis, have become an important option for many patients with non-small cell lung cancer (NSCLC). Activity was first demonstrated in Eastern Cooperative Oncology Group E4599, a large phase 3 trial that randomized patients with newly diagnosed, nonsquamous NSCLC to receive carboplatin/paclitaxel with or without bevacizumab at 15 mg/kg every 3 weeks. The study demonstrated significant improvements in response rate, progression-free survival, and overall survival with the addition of bevacizumab. Median overall survival improved from 10.3 to 12.3 months (p = 0.003). Significant toxic effects, including fatal hemoptysis, however, resulted in 15 treatment-related deaths in the bevacizumab arm. The beneficial results were recently confirmed in the European Avastin in Lung Cancer B017704 (AVAiL) trial. In AVAiL, patients with newly diagnosed nonsquamous NSCLC were randomized to receive cisplatin/gemcitabine with or without bevacizumab at doses of either 7.5 or 15 mg/kg every 3 weeks. Both doses resulted in statistically significant improvements in response rate and progression-free survival, but overall survival results have yet to be presented. Based on these encouraging results, the drug is now being studied in earlier-stage disease as neoadjuvant or adjuvant therapy and in locally advanced NSCLC. Exploration of the safety and efficacy of the drug in combination with other chemotherapeutics and targeted agents, and in previously excluded patient populations such as those with brain metastases, is also ongoing.