Interference in immunoassays to support therapeutic antibody development in preclinical and clinical studies.

During preclinical and clinical studies, immunoassays are used to measure the concentration of the therapeutic antibody, anti-drug antibodies and soluble protein biomarkers. The reliability of these assays is crucial since the results are routinely used for safety assessment and dose selection. Furthermore, soluble protein biomarkers can provide information about target engagement, proof of mechanism, proof of principle and prediction of response. Study samples mostly consist of complex matrices that can exhibit considerable interference, resulting in inaccurate measurements. This perspective discusses the source of interference and strategies to mitigate or eliminate interference in immunoassays used during preclinical and clinical drug development of drugs with a focus on the development of therapeutic antibodies.