OSI-027 is a selective and potent dual inhibitor of mTORC1 and mTORC2 with IC50 of 22 nM and 65 nM, respectively. It shows more than 100-fold selectivity for mTOR relative to PI3Kα, PI3Kβ, PI3Kγ, and DNA-PK. It inhibits phosphorylation of the mTORC1 substrates 4E-BP1 and S6K1 as well as the mTORC2 substrate AKT in diverse cancer models in vitro and in vivo. OSI-027 shows robust antitumor activity in several different human xenograft models representing various histologies. In COLO 205 and GEO colon cancer xenograft models, OSI-027 showed superior efficacy compared with rapamycin. OSI-027 is currently in Phase I clinical trials in patients with advanced solid tumors or lymphoma.