Practical approaches to incurred sample LC-MS/MS reanalysis: confirming unexpected results

Area of Science:

• Pharmacokinetics and Drug Metabolism
• Analytical Chemistry
• Bioanalytical Science

Background:

• Incurred sample reanalysis (ISR) is vital for ensuring the quality and integrity of LC-MS/MS bioanalytical assays.
• Conventional ISR, involving re-analysis of study samples, may be insufficient for confirming unexpected bioanalytical results.
• Investigational drug NVP-1 in a Phase II trial presented unexpected plasma concentration-time data requiring further investigation.

Purpose of the Study:

• To discuss and evaluate additional exploratory activities for confirming unexpected plasma concentration-time results of NVP-1.
• To present practical methods that can enhance the confirmatory bioanalysis of small molecules.

Main Methods:

• LC-MS/MS reanalysis of study samples after multiple freeze/thaw cycles and short-term benchtop storage.
• Evaluation of additional MS/MS transitions during LC-MS/MS analysis.
• Application of a different sample preparation procedure for LC-MS/MS.
• Dilution of study samples using plasma from healthy volunteers.

Main Results:

• The discussed exploratory activities provide practical approaches for confirming unexpected bioanalytical findings.
• These methods can be readily implemented in routine confirmatory LC-MS/MS bioanalysis.
• The study successfully confirmed unexpected results for NVP-1.

Conclusions:

• Conventional ISR may not always be adequate for unexpected bioanalytical results.
• Additional exploratory LC-MS/MS methods offer robust solutions for data confirmation.
• These enhanced techniques improve the reliability of bioanalytical data in clinical studies.