Onatasertib (CC-223) 是一種口服有效的 mTOR 激酶抑制劑，抑制 mTOR 激酶，IC₅₀ 為 16 nM。Onatasertib 抑制 mTORC1 和 mTORC2。The antitumor activity of Onatasertib in the PC-3 xenograft model is determined using a number of dosing paradigms. Onatasertib significantly inhibits PC-3 tumor growth in a dose- and schedule-dependent manner. Dosing at 10 or 25 mg/kg, once daily, results in 46% (P<0.001) and 87% (P<0.001) reduction in tumor volume, respectively. Similar dose dependency is observed with twice-daily dosing at 5 or 10 mg/kg, corresponding to 65% (P<0.001) and 80% (P<0.001) tumor volume reductions. All dose levels are tolerated in the once-daily and twice-daily dosing studies, with only the 25 mg/kg/d group showing any significant body weight loss. These mice lost approximately 10% of their initial body weight after 3 weeks of dosing