Discovery of bepridil as a valuable lead compound with potent p53-MDM2 inhibitory activity / 药学实践杂志

Objective To find novel lead compounds as p53-MDM2 inhibitors by drug repurposing strategy. Methods The p53-MDM2 inhibitory activities of compounds were determined by FP and western blotting. MTT method was used to determine the in-vitro antitumor activities. The metabolites in human liver microsomes were tested. Results Bepridil showed excellent in-vitro anti-tumor activity and strong p53-MDM2 protein binding inhibitory activity, which can significantly reduce the expression of MDM2 protein in a dose-dependent manner. The metabolites in human liver microsomes are mainly benzene ring hydroxyl mono-oxidation metabolites. Conclusion Bepridil can be used as a lead compound for p53-MDM2 protein binding small molecule inhibitors for subsequent structural optimization design studies.

Pharmacokinetics and metabolism of AMG 232, a novel orally bioavailable inhibitor of the MDM2-p53 interaction, in rats, dogs and monkeys: in vitro-in vivo correlation.

1. AMG 232 is a novel inhibitor of the p53-MDM2 protein-protein interaction currently in Phase I clinical trials for multiple tumor indications. The objectives of the investigations reported in this article were to characterize the pharmacokinetic and drug metabolism properties of AMG 232 in pre-clinical species in vivo and in vitro, and in humans in vitro, and to predict its pharmacokinetics in humans through integrating PKDM data. 2. AMG 232 exhibited low clearance (<0.25 × Qh) and moderate to high oral bioavailability in mice, rats and monkeys (>42%), but high clearance (0.74 × Qh) and low oral exposure in dogs (18%). 3. Biotransformation was the major route of elimination of AMG 232 in rats, with only 7% of intravenously administered (14)C-labeled AMG 232 recovered as parent molecule in bile. The major metabolite was an acyl glucuronide as measured by in vivo rat studies and in vitro hepatocyte incubations in multiple species. 4. The in vitro-in vivo correlation of AMG 232 clearance was within 2-fold in pre-clinical species using hepatocytes. AMG 232 was predicted to exhibit low clearance, high volume distribution and long half-life in humans. The predictions are consistent with the preliminary human pharmacokinetic parameters of AMG 232 in clinical trials.

Discovery of 1-arylpyrrolidone derivatives as potent p53-MDM2 inhibitors based on molecule fusing strategy.

Introducing an aryl moiety to our previous pyrrolidone scaffold by molecule fusing strategy afforded two sets of isopropylether-pyrrolidone and α-phenylethylamine-pyrrolidone derivatives. Two novel compounds 8b and 8g of the latter serial showed potent p53-MDM2 inhibitory activities with Ki values of 90nM which were three-time higher than that of the parent compound. We also confirmed compound 8b can activate p53 proteins in lung cancer A549 cells. The results offered us valuable information for further lead optimization.