RAD001 is an orally administered cell cycle inhibitor with antitumor activity. RAD001, like Rapamycin, binds with high affinity to an intracellular immunophilin, FKBP12 and this complex specifically interacts with the mammalian target of rapamycin (mTOR) protein kinase, inhibiting downstream events such as the initiation of mRNA translation. RAD001 inhibits the growth of a wide range of histologically diverse tumor cells. RAD001 is being developed as a cytostatic agent to delay the time to tumor recurrence/progression or to increase survival in patients with various malignancies. The compound has good tolerability, a partially discovered mechanism of action. RAD001 has the ability to arrest cells in the G1 phase, and the ability to induce apoptosis. RAD001 is being investigated as an anticancer agent based on its potential to act directly on the tumor cells by inhibiting tumor cell growth and proliferation through possible inhibition of the PI3/AKT/MTOR pathway.