Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Jul 1;24(4):78.
doi: 10.1208/s12248-022-00729-7.

Pre-existing Reactivity to an IgG4 Fc-Epitope: Characterization and Mitigation of Interference in a Bridging Anti-drug Antibody Assay

Michael A Partridge #  1 , Jihua Chen #  2 , Elif Kabuloglu Karayusuf  2 , Thanoja Sirimanne  2 , Colin Stefan  2 , Ching Ha Lai  2 , Meghna Gathani  2 , Lisa DeStefano  2 , Michal Rozanski  2 , Sean McAfee  2 , Manoj Rajadhyaksha  2   3 , Matthew D Andisik  2 , Albert Torri  2 , Giane Sumner  2
Affiliations

Pre-existing Reactivity to an IgG4 Fc-Epitope: Characterization and Mitigation of Interference in a Bridging Anti-drug Antibody Assay

Michael A Partridge et al. AAPS J. .

Abstract

Twenty percent of baseline patient samples exhibited a pre-existing response in a bridging anti-drug antibody (ADA) assay for a human IgG4 monoclonal antibody (mAb) therapeutic. In some cases, assay signals were more than 100-fold higher than background, potentially confounding detection of true treatment-emergent ADA responses. The pre-existing reactivity was mapped by competitive inhibition experiments using recombinant proteins or chimeric human mAbs with IgG4 heavy chain regions swapped for IgG1 sequences. These experiments demonstrated that the majority of the samples had reactivity to an epitope containing leucine 445 in the CH3 domain of human IgG4. The pre-existing reactivity in baseline patient samples was mitigated by replacing the ADA assay capture reagent with a version of the drug containing a wild type IgG1 proline substitution at residue 445 without impacting detection of drug-specific, treatment-emergent ADA. Finally, purification on Protein G or anti-human IgG (H + L) columns indicated the pre-existing response was likely due to immunoglobulins in patient samples.

Keywords: Anti-drug antibody (ADA); Autoantibody; IgG4; Immunogenicity; Monoclonal antibody therapeutic; Pre-existing antibody.

PubMed Disclaimer

References

    1. Casadevall N, Nataf J, Viron B, Kolta A, Kiladjian JJ, Martin-Dupont P, et al. Pure red-cell aplasia and antierythropoietin antibodies in patients treated with recombinant erythropoietin. N Engl J Med. 2002;346(7):469–75. - DOI
    1. Bartelds GM, Krieckaert CL, Nurmohamed MT, van Schouwenburg PA, Lems WF, Twisk JW, et al. Development of antidrug antibodies against adalimumab and association with disease activity and treatment failure during long-term follow-up. JAMA. 2011;305(14):1460–8. - DOI
    1. US F. Guidance for industry immunogenicity assessment for therapeutic protein products. 2014.
    1. Agency EM. Guideline on immuogenicity assessment of therapeutic prtoeins. 2017.
    1. Koren E, Smith HW, Shores EW, Shankar G, Finco-Kent D, Rup B, et al. Recommendations on risk-based strategies for detection and characterization of antibodies against biotechnology products. J Immunol Methods. 2008;333(1–2):1–9. - DOI

LinkOut - more resources