Bioanalytics – Biomolecular
2019 PharmSci 360
FDA Final guidelines recommend that the sensitivity for immunogenicity assays be at least 100 ng/mL. As a result, assay sensitivity plays a pivotal role when determining if a method is fit-for-purpose. In addition, assay sensitivity is also used to calculate the concentration of the low positive control targeted to fail in 1% of assays. Despite these significant roles during assay development and characterization, the perceived sensitivity of a method may be manipulated by numerous experimental variables. Significant differences may be observed when using monoclonal vs polyclonal positive controls. However, the number of analysts, days, reagent/buffer preparations and instruments used for sensitivity assessment are also impactful to the reported assay sensitivity value. The relationship of these variables will be described for an electrochemiluminescent bridging ADA method. As well, assay performance will be evaluated over time and recommendations for effective positive control placement will be provided.