The treatment of cancer by targeting angiogenesis and depriving growing tumors of their blood supply has been recognized as an interesting therapeutic possibility for several decades. A multitude of development programs investigating both low-molecular-weight substances and biologicals, in particular monoclonal antibodies (mAbs), have been instigated. The generation of human or human-like mAbs has led to the recent development of therapeutic antibodies that are potentially highly beneficial in the treatment of cancer. Avastin, which binds to the pro-angiogenic factor vascular endothelial growth factor, is one of the most promising of these antibodies, and has proved beneficial in the treatment of colorectal, lung and breast cancer, with a potential to be used also in other types of cancer. However, as angiogenesis is a complex process controlled by both pro-angiogenic as well as anti-angiogenic factors, several research and development programs targeting different pro-angiogenic factors, receptors and antigens that are selectively expressed on cells in newly formed blood vessels are under way. At BioInvent International AB, research is focused on angiomotin, a newly discovered receptor for the anti-angiogenic factor angiostatin, and on the pro-angiogenic factor placenta growth factor.