Sunitinib (marketed as Sutent, previously known as SU11248) is a small molecule receptor tyrosine kinase inhibitor that is approved for the treatment of gastrointestinal stromal tumor (GIST) and renal cell carcinoma (RCC).

In a separate study, Sutent shrank tumors in 51 percent of patients in the advanced stages of lung cancer, for whom other forms of treatment did not work. This lung cancer study was "phase 2," meaning that it was not as advanced as the "phase 3" kidney cancer study. Phase 3 is generally the most advanced stage of study before submitting a drug to the Food and Drug Administration for approval.

Dr. Mark Socinski, the lead researcher in the lung cancer study who is an associate professor at the University of North Carolina's oncology program, acknowledged that the study was still in the early stages, but said that Sutent "could have a place in the treatment of lung cancer, either alone or in combination with other agents."
*The most commonly reported Sutent-related side effects?*