VALIDITY OF BIOMARKERS
To identify biomarkers as surrogate – primary or secondary- endpoints in clinical trials, the relevance and validity of biomarkers need to be determined. Relevance means that a biomarker will actually provide clinically relevant information. Validity refers to the need to characterize a biomarker’s effectiveness or utility as a surrogate endpoint.
For clinical studies the following levels of laboratory biomarker validity – or levels of surrogacy success- must be considered and evaluated:
- Measurement Validity: is the biomarker proposed as a surrogate capable of being measured objectively and reproducibly in any given case? Does it measure an objective, quantifiable characteristic successfully?
- Study Validity: Can the biomarker be measured with accuracy within the study? Does the biomarker correlate strongly with the associated clinical endpoint within the study population?
Biomarkers have become an integral part of the decision-making process in drug development and therefore, biomarker applications require data to demonstrate the validity of the biomarker assessment.
Different purposes for the use of the data
require different approaches: validate vs. verify.
Verification and validation procedures go hand-in-hand to prove that a laboratory biomarker assay meets its requirements, specifications and that it fulfills its intended purpose. These procedures are critical components of the quality management system used at Eurofins Central Laboratory.
VERIFICATION OF BIOMARKER ASSAYS
For global clinical studies, it is important that there is global harmonization between different laboratory locations, enabling patient inclusion regardless of where the laboratory test result is generated. Clinical analyzers and their associated testing kits find great utility in conducting such tests, for which method verification of manufacturer specifications is often sufficient for the use in clinical (CAP/CLIA) laboratories.
Verification of biomarker assays is intended to reproduce commercially available assays.
The purpose of verification is to meet a set of assay specifications in compliance with CAP/CLIA.