The aim of measurements of ADA is to predict the potential of the test item to induce ADA with all consequences for toxicological effects, test item kinetics and efficacy.
Part of a toxicity study or clinical trial.
Anti-drug antibody assay is usually an ELISA-based screening assay which is validated for the given antibody product. The target analyte is generally polyclonal, consisting of antibodies of various isotype classes, specificities and affinities. As a result of the nature of the assay and the lack of an accurate reference standard (parallelism between sample and calibrator is not given for antibodies) a threshold value will be used to identify positive samples from non-specific background noise. Therefore, for each assay an assay cut point is set with the application of a risk-based approach. This is done by a parametric approach using the mean absorbance of blank samples plus 1.645 x standard deviation, where 1.645 is the 95th percentile of the normal distribution.
In a first step the method is established and subsequently, method validation is performed. The following parameters are tested during method validation: