A monoclonal antibody being studied in the treatment of some types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. Anti-VEGFR monoclonal antibodies bind to receptors for vascular endothelial growth factor (VEGF) and keeps VEGF from binding to them. This may stop the growth of new blood vessels that tumors need to grow. It is a type of antiangiogenesis agent.