SU11248 sunitinib malate sutent is a selective inhibitor of certain protein tyrosine kinases including VEGF-R types 1-3 PDGF-R-a and -b, c-kit, and RET. Its antitumor activity may result from both inhibition of angiogenesis and direct antiproliferative effects on certain tumor types. In several phase I/II/III studies, sutent was found to be effective as second and first line treatment in metastatic renal cell carcinoma (RCC). In fact, with a 37% response rate and an additional 48% stable disease sutent became the drug of choice for first line treatment in RCC. Sutent was also effective as second line treatment in patients with gastrointestinal stromal tumors (GIST) with 8% response rate, 70% stable disease and a 20-month median survival. Prolonged stable disease was also documented in neuroendocrine tumors. In addition, a phase II study in multitreated women with breast cancer, sutent demonstrated a moderate activity with 16% clinical benefit. Finally, in non-small cell lung cancer (NSCLC) in patients' progressing on chemotherapy sutent was able to achieve a 10% response rate, a level of activity similar to those documented by other agents approved for lung cancer. The agent is being tested in other tumors with a modified schedule of dosage.