Description:
IC50 Value: 9.9 nM [1]
XL388 is a novel, highly potent, selective, and ATP-competitive mammalian target of rapamycin (mTOR) inhibitor.
in vitro: Compound 28 (XL388) inhibited cellular phosphorylation of mTOR complex 1 (p-p70S6K, pS6, and p-4E-BP1) and mTOR complex 2 (pAKT (S473)) substrates.Furthermore, this compound displayed good pharmacokinetics and oral exposure in multiple species with moderate bioavailability. Oral administration of compound 28 to athymic nude mice implanted with human tumor xenografts afforded significant and dose-dependent antitumor activity [1].
in vivo: XL388 resulted in complete inhibition of MCF-7 xenograft tumor growth at both doses, with significant tumor regression of 22% and 40% below pretreatment values at the 50 and 100 mg/kg doses, respectively. Furthermore, 28 does not appear to show significant toxicity. Mice in the 50 mg/kg cohort over the course of the study gained on average 2.2% additional mass, while those in the 100 mg/kg cohort lost on average 2.8% of their body mass [1].
Clinical trial: N/A