Non-specificity fingerprints for clinical stage antibodies in solution

Monoclonal antibodies (mAbs) have successfully been developed for the treatment of a wide range of diseases. The clinical success of mAbs, does not solely rely on optimal potency and safety, but also require good biophysical properties to ensure high developability potential. In particular, non-specific interactions are a key developability measure to monitor during discovery. Despite an increased focus on the detection of non-specific interactions, their physicochemical origins remain poorly understood. Here, we employ solution-based microfluidic technologies to characterise a set of clinical stage mAbs and their interactions with commonly used non-specificity ligands to generate non-specificity fingerprints, providing quantitative data on the underlying physical chemistry. Furthermore, the solution-based analysis enables us to evaluate the contribution of avidity in non-specific binding by mAbs. Based on our findings, we propose a quantitative solution-based non-specificity score, which can be exploited in the development of biological therapeutics and more widely in protein engineering. ### Competing Interest Statement The authors have declared no competing interest.