Selectivity of ligand-binding assays in relationship to the measurement of biologics: how much does it matter?

“Findings of metabolism can be relevant to the pharmacological activity of the drug ... therefore application of protein metabolism to the discovery process should be an exciting and interesting approach for the future.” While technologies for determining the potency and structural identity of macromolecules have developed significantly over recent years, the relationship between potency and structure is still an issue. Ligand-binding assays (LBA) may respond equally to related molecules that have the same epitope, but differ in their activity/potency. This is especially important in human following dosing, where the metabolites may significantly contribute to biological activity, but may (or may...