Comparison of competitive ligand-binding assay and bioassay formats for the measurement of neutralizing antibodies to protein therapeutics

• Published in: Journal of pharmaceutical and biomedical analysis 2011-01, Vol.54 (2), p.351-358
• Main Authors: Finco, Deborah, Baltrukonis, Daniel, Clements-Egan, Adrienne, Delaria, Kathy, Gunn, George R., Lowe, John, Maia, Mauricio, Wong, Teresa
• Format: Article
• Language: English
• Subjects: Analysis; Analytical, structural and metabolic biochemistry; Antibodies - analysis; Antibodies - immunology; Antibodies, Neutralizing - analysis; Antibody Formation - immunology; Binding, Competitive; Bioassay; Biological and medical sciences; Biological Assay - methods; Biological Products - analysis; Biological Products - immunology; Biotechnology - methods; CLB assay; Drug-Related Side Effects and Adverse Reactions; Fundamental and applied biological sciences. Psychology; General pharmacology; Humans; Immunogenicity; Ligands; Medical sciences; Neutralizing antibodies; Pharmacology. Drug treatments
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/j.jpba.2010.08.029

Administration of biological therapeutic proteins can lead to unwanted immunogenicity in recipients of these products. The assessment and characterization of such immune reactions can be helpful to better understand their clinical relevance and how they relate to patient safety and therefore, have become an integral part of a product development program for biological therapeutics. Testing for anti-drug antibodies (ADA) to biological/biotechnology-derived therapeutic proteins generally follows a tiered approach. Samples are initially screened for binding antibodies; presumptive positives are then confirmed in a confirmatory assay; subsequently, confirmed-positive samples may be further characterized by titration and with a neutralizing antibody (NAb) assay. Regulatory guidances on immunogenicity state that assessing the neutralizing capacity of antibodies should preferably be done using functional bioassays, while recognizing that competitive ligand-binding (CLB) assays may be substituted when neutralizing bioassays are inadequate or not feasible. This manuscript describes case studies from four companies in which CLB assays and functional bioassays were compared for their ability to detect neutralizing ADA against a variety of biotechnology-derived therapeutic proteins. Our findings indicate that CLB assays are comparable to bioassays for the detection of NAbs, in some cases offering better detection sensitivity, lower variability, and less matrix interference.