Anti-drug Antibody Validation Testing and Reporting Harmonization Addendum

The anti-drug antibody validation testing and reporting harmonization (ADAH) white paper was published December 2021 and has generated significant interest, highlighting its utility within the scientific community. Following the ADAH white paper, members of the American Association of Pharmaceutical Scientist (AAPS) Therapeutic Product Immunogenicity community published a similar white paper addressing neutralizing antibody validation testing and reporting harmonization (NAbH) in July 2023 which has also been broadly accessed. Given the broad interest in these white papers by the bioanalytical and immunogenicity communities, the authors have solicited user feedback to address noted gaps. This feedback has prompted us to issue an addendum to address these gaps including adding a section on anti drug antibody (ADA) assay cross-validation and ADA data presentation for regulatory submissions, and to update the method sensitivity assessments. In addition, given recent year discussions around the implementation of signal to noise over titer, a section on this topic is included.