Sample re-analysis may be required for numerous reasons. Assay failure is the most common and the clearest. Individual re-analysis is usually justified by the lack of internal standards or the failure to meet chromatographic parameters such as retention time or peak shape. In ligand binding assays and chromatographic assays, the color or peak height may exceed expectations or fall below expectations. These   failures may be due to several causes, some lab-related and some study or in-life-related

To justify re-analysis for individual samples a lab investigation should be opened with a requirement for a lab investigation to publish findings. For example, in the case of poor peak shape, an error in addition to a kind of extraction or re-suspension media may have caused the issue. Perhaps an internal standard was not added. In the case of responses being below or above expectations the laboratorian may have incorrectly diluted the sample. Again, a lab investigation with hypotheses should be written and a lab report filed. Before undertaking any lab investigation, the lab collecting the sample should be queried. Low samples may have resulted from taking the sample too soon or too late. A very high sample may similarly result from too soon a collection after dosing, collection for the same site as the dosing, or collecting too late. These causal factors must be excluded before risking samples.

Areas Covered

Protocol and SOP coverage of when and how to re-analyze samples. Hypothesis formation and testing. Protocol and SOP for laboratory investigation, including participants and the review and issuance of the investigation report.

Who Should Attend

Directors, Managers and Supervisors, Analysts and QA

Why Should You Attend

This Webinar will outline procedures for sample re-analysis in GxP analytical work supporting registration and filing. This seminar will also compare current and previous approaches and guidance documents.

This Webinar will provide suggestions to avoid compliance issues, keep the project on schedule, and minimize audit findings related to re-analysis.

Topic Background

Predicate rule for sample reanalysis, when to re-analyze, steps suggested to be applied before re-analysis.