Evaluation of criteria for the acceptance of bioanalytical data

Results from bioanalytical analyses for registration of a new drug entity are used to define its pharmacokinetics and bioavailability/bioequivalence. Whilst analytical data may be derived from the application of a validated method, it is essential to apply mathematical criteria to its acceptance, in order that the analyst can be assured that the assay is performing within defined limits and to its validated specification. Parameters evaluated for acceptability are the batch calibration curve, the minimum quantifiable concentration and the quality control (QC) sample acceptability. Specifically, six QC samples per analytical batch are used, two samples at each of three concentrations. The rationale for the definition of these criteria is evaluated together with a consideration of their applications and limitations. The relevance and use of Shewhart and Cusum plots to monitor assay performance is illustrated.