motesanib (amg 706) is an experimental drug candidate originally developed by amgen but later investigated by the takeda pharmaceutical company. it is an orally administered small molecule belonging to angiokinase inhibitor class which acts as an antagonist of vegf receptors, platelet-derived growth factor receptors, and stem cell factor receptors. it is used as the phosphate salt motesanib diphosphate. after clinical trials in thyroid cancer, non-small cell lung cancer, gastrointestinal stromal cancer, colorectal cancer, and breast cancer, the drug was not found to show sufficient efficacy for further development, and development was abandoned by takeda.