Review of Recommendations for Bioanalytical Method Validation: Chromatographic Assays and Ligand Binding Assays

Abstract

Reliable bioanalytical tools for compound selection as well as studies of pharmacokinetics, pharmacodynamics, and toxicity are an important part of preclinical and clinical development. Developing a selective and specific analytical method in today’s regulated bioanalysis framework is a formidable challenge for the analyst. The molecular structure and weight of analytes determine the method to be applied. Chromatographic assay (CC), predominantly liquid chromatography coupled with mass spectrometry, is the method of choice for measurement of small molecule concentrations in the biological matrix. For quantification of large molecules such as peptides and proteins, the gold standard is the ligand binding assay (LBA). LBAs differ substantially from CC methods; hence the recommendations for their validation differ too. Recently published (May 2018) United States Food and Drug Administration guidelines for bioanalytical method validation include a number of elements and acceptance criteria for CCs and LBAs individually. The differences in the requirements are based on the principles of analysis. This review summarizes the differences between small and large molecules, CCs, LBAs, and elements for bioanalytical method validation.