Quantification of Abemaciclib and Metabolites: Evolution of Bioanalytical Methods Supporting a Novel Oncolytic Agent

Abstract

Aim: Bioanalytical methods undergo many revisions and modifications throughout drug development to meet the objectives of the study and development program. Results: Validated LC–MS/MS methodology used to quantify abemaciclib and four metabolites in human plasma is described. The method, initially validated to support the first-in-human study, was successfully modified to include additional metabolites as in vitro and in vivo information about the activity and abundance of human metabolites became available. Consistent performance of the method over time was demonstrated by an incurred sample reanalysis passing rate exceeding 95%, across clinical studies. An overview of the numerous methods involved during the development of abemaciclib, including the quantification of drugs evaluated as combination regimens and used as substrates during drug–drug interaction studies, is presented. Conclusion: Robust bioanalytical methods need to be designed with the flexibility required to support the evolving study objectives associated with registration and post-registration trials.

Simultaneous determination of LY3214996, abemaciclib, and M2 and M20 metabolites in human plasma, cerebrospinal fluid, and brain tumor by LC-MS/MS

“…The benchtop, autosampler, processed sample, and long-term stability results for all analytes are presented in Tables S5 −S8 and are summarized in Table 5 . The observed stability results are in agreement with previously published data on abemaciclib and its metabolites [ [18] , [19] , [20] ].…”

“…3 B). Compared to previously published assays for abemaciclib [ [18] , [19] , [20] ], the present method demonstrated at least 10-fold better sensitivity (0.2 nM versus 2 [ 18 ], 4 [ 20 ], and 200 nM [ 19 ]) and a larger linear dynamic range (2500-fold versus 100 [ 19 , 20 ] or 500 nM [ 18 ]). No bioanalytical method has been reported for LY3214996.…”

“…Herein, we report a validated liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of LY3214996, abemaciclib, and M2 and M20 metabolites in the plasma, GBM tissue, and CSF of selected patients. Compared to the reported assays for abemaciclib [ [18] , [19] , [20] ], the present method demonstrated at least 10-fold better sensitivity (lower limit of quantification is 0.2 nM), a larger dynamic range (0.2–500 nM), and a minor post-injection carryover, while the sample preparation involved a simple one-step protein precipitation. To our knowledge, no validated assays have been reported for the determination of LY3214996 levels in any biological specimen.…”

An UHPLC-MS/MS method for quantification of the CDK4/6 inhibitor abemaciclib in human serum

“…Therefore, a biphenyl column was tested, which showed good overall chromatographic performance. A few LC-MS/MS methods or chromatographic conditions have been published for the analysis of abemaciclib: C18 columns with alkaline or acidified mobile phases have been described by Martinéz-Chávez et al [10] , [19] , Wickremsinhe et al [20] , and Kadi et al [21] , respectively, with protein precipitation performed for sample cleanup. The herein developed sample preparation consisted of a manual protein precipitation step followed by an automated on-line sample clean-up using a hydrophilic-lipophilic balanced reversed-phase sorbent.…”

“…There are only a few methods, all of which are based on LC-MS/MS techniques, that describe the analyses of the CDK4/6 inhibitor abemaciclib in mouse and/or human plasma. The published methods are research methods based solely on manual sample preparation, and some are not directly applicable to human material due to its narrow calibration range [10] , [19] , [20] , [21] .…”