A drug used alone or with other drugs to treat certain types of cervical, colorectal, lung, and kidney cancer, and glioblastoma (a type of brain cancer). It is also used to treat certain types of ovarian epithelial, fallopian tube, and primary peritoneal cancer. Avastin is also being studied in the treatment of other types of cancer. It binds to a protein called vascular endothelial growth factor (VEGF). This may prevent the growth of new blood vessels that tumors need to grow. Avastin contains the active ingredient bevacizumab. It is a type of antiangiogenesis agent and a type of monoclonal antibody.