Temsirolimus (codenamed CCI-779) is an intravenous drug for the treatment of renal cell carcinoma (RCC), developed by Wyeth Pharmaceuticals and approved by the U.S. Food and Drug Administration (FDA) in late May 2007,[2] and was also approved by the European Medicines Agency (EMEA) on November 2007. It is a derivative and prodrug of sirolimus and is sold as Torisel.