Aim: The work was aimed at developing a bioanalytical approach to identify immunogenic parts of a bispecific F(ab) fragment and to characterize the immune response seen in a preclinical study. Experimental: The bioanalytical method consists of a set of domain detection assays that use germlined variants of the drug. Results: The method demonstrated that anti-drug antibodies (ADAs) were predominantly directed against both antigen-binding sites of the drug. Conclusion: The method was capable to discriminate between ADAs directed against one of the antigen-binding sites, both sites or the constant domain, allowing for an estimation of the relative binding prevalence for these subunits. The developed approach provides a practical and robust solution for exploratory characterization of ADAs against multidomain biotherapeutics.
Keywords:
- ADA
- anti-drug antibody
- bispecific F(ab)
- DDA
- domain detection assay
- immunogenicity response characterization
- MDB
- multi-domain biotherapeutic