Abstract The development of monoclonal antibodies (mAbs) counts as one of the major medical steps forward, opening up endless possibilities for research, diagnosis, and treatment of a wide range of various diseases and disorders. Development of both humanized and fully human mAbs was expected to be non-immunogenic, that allow repeated administration without any anti-drug antibodies (ADA) responses. Unfortunately, these expectations have proven to be unrealistic. They fail to completely eliminate mAb immunogenicity and ADA formation; they have reduced the extreme immunogenicity associated with murine origin mAbs, but still, they have shown to induce antibodies that sometimes have an impact on clinical outcomes. Understanding the mechanisms of ADA generation and then factors that may influence the immunogenicity of mAbs will help us design mAbs with lower immunogenic responses. Accurate ADA detection is necessary, to provide sufficient information for patient monitoring and clinical intervention. However, ADA assays for mAb have more challenges as both the analyte and antigen (mAb) are antibodies. This short communication discusses the assessment of mAbs immunogenicity. First, we provided an overview about the development of different generations of mAbs and the immunogenicity developed upon their administration. Additionally, we also provided a conclusive review about various types of methods and their principles that have been used for assays of ADA as well as those developed for the detection of anti-trastuzumab Ab used in our study. Finally, we summarized the results and conclusions observed in our study and discussed future prospects for studying ADA developed against mAbs.

PImmunogenicity, Monoclonal Abs, ADA assays, Trastuzumab