title: In vitro ADME profiling using high-throughput rapidfire mass spectrometry: cytochrome p450 inhibition and metabolic stability assays.
abstract: Early assessment of absorption, distribution, metabolism, and excretion (ADME) properties of drug candidates has become an essential component of modern drug discovery. ADME characterization is important in identifying compounds early that are likely to fail in later clinical development because of suboptimal pharmacokinetic properties or undesirable drug-drug interactions. Proper utilization of ADME results, meanwhile, can prioritize candidates that are more likely to have good pharmacokinetic properties and also minimize potential drug-drug interactions. By integrating a RapidFire system with an API4000 mass spectrometer (RF-MS), we have established a high-throughput capability to profile compounds (>100 compounds/wk) in a panel of ADME assays in parallel with biochemical and cellular characterizations. Cytochrome P450 inhibition and time-dependent inhibition assays and microsomal stability assays were developed and fully optimized on the system. Compared with the classic liquid chromatography-mass spectrometry method, the RF-MS system generates consistent data with approximately 20-fold increase in throughput. The lack of chromatographic separation of compounds, substrates, and metabolites can complicate data interpretation, but this occurs in a small number of cases that are readily identifiable. Overall, this system has enabled a real-time and quantitative measurement of a large number of ADME samples, providing a rapid evaluation of clinically important drug-drug interaction potential and drug metabolic stability.
authors.affiliation: New Lead Discovery, Exelixis, Inc., South San Francisco, CA, USA.
authors.forename: Xiang
authors.initials: X
authors.lastname: Wu
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Lory
authors.initials: L
authors.lastname: Tan
authors.forename: John
authors.initials: J
authors.lastname: Bui
authors.forename: Erik
authors.initials: E
authors.lastname: Gjerstad
authors.forename: Kirk
authors.initials: K
authors.lastname: McMillan
authors.forename: Wentao
authors.initials: W
authors.lastname: Zhang
mesh_terms: D000327:Adsorption; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D065607:Cytochrome P-450 Enzyme Inhibitors; D004285:Dogs; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D004347:Drug Interactions; D004355:Drug Stability; D000882:Haplorhini; D057166:High-Throughput Screening Assays / Q000379:methods*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods; D051379:Mice; D008862:Microsomes, Liver / Q000378:metabolism*; D010599:Pharmacokinetics; D051381:Rats; D052616:Solid Phase Extraction
chemical_list: D065607:Cytochrome P-450 Enzyme Inhibitors