An Ex Vivo Potency Assay to Assess Active Drug Levels of A Glp-1 Agonistic Peptide During Preclinical Safety Studies

Abstract

We were able to show that despite a high total test compound level, activity was reduced tremendously in antidrug-antibody-positive monkeys. Therefore, the applied ex vivo potency assay supplements drug quantification methods to determine active exposures.

BI 456906: Discovery and preclinical pharmacology of a novel GCGR/GLP-1R dual agonist with robust anti-obesity efficacy

“…Upon termination of the study, an ex vivo bioactivity assay [ [48] , [49] , [50] ] was carried out on plasma samples to determine drug exposures and the relative bioactivity for the human GLP-1R and GCGR ( Figure 3 N; Table S2 ) to support the interpretation of the pharmacokinetic and pharmacodynamic profiles of the two peptides ( Table S1 ). Diluted plasma samples were used to determine the nM activity and relative bioactive fraction (EC 50 ) for BI 456906 and semaglutide at the GLP-1R ( Figure S4 ) and the GCGR ( Figure S5 ).…”

Comprehensive Review on the Degradation Chemistry and Toxicity Studies of Functional Materials

“…The ex vivo potency assay provides the methods for PK/PD assessment in a chronic toxicity study with the aim to understand active drug exposure. 310 In the future, this method will be used to explore the potency of drug−functional material conjugates.…”

“…In this assay, analysis of the plasma samples withdrawn from experimental animals was carried out in a cell-based readout system where peptide activity in the unknown sample was compared with a spiked predose sample of the same animal. The ex vivo potency assay provides the methods for PK/PD assessment in a chronic toxicity study with the aim to understand active drug exposure . In the future, this method will be used to explore the potency of drug–functional material conjugates.…”

Proposal for A Harmonized Descriptive Analyte Nomenclature for Quantitative Large-Molecule Bioanalysis

“…It is common understanding that immune responses against the drug occur for basically all large molecules whether they are of animal, humanized or human origin, which to a certain percentage may neutralize the potency of the drug [2]. It is, therefore, obvious that a correlation of only the absolute total drug concentrations to PD, efficacy and safety can be misleading and may not be sufficient to describe the efficacious and safe dose [3]. Consequently, much effort has been invested in the past years to quantify certain forms of the drug molecule, such as the quantification of the subfraction of 'active (potent) drug' molecules, 'free drug' or, as an alternative approach, to understand the impact of ADAs on the potency of drug by, for example, neutralizing ADA assays or ex vivo potency assays [3][4][5][6].…”

“…It is, therefore, obvious that a correlation of only the absolute total drug concentrations to PD, efficacy and safety can be misleading and may not be sufficient to describe the efficacious and safe dose [3]. Consequently, much effort has been invested in the past years to quantify certain forms of the drug molecule, such as the quantification of the subfraction of 'active (potent) drug' molecules, 'free drug' or, as an alternative approach, to understand the impact of ADAs on the potency of drug by, for example, neutralizing ADA assays or ex vivo potency assays [3][4][5][6]. Neutralizing assays are, however, only of qualitative nature describing the potential impact of ADAs on the drug and cannot be used to quantify or mathematically calculate the remaining potent fraction of the drug.…”