ABSTRACT
Biomarkers hold a key role in advancing personalized medicine strategies and targeted therapies by stratifying patients, matching the right patient to the right clinical trials, and minimizing the potential for adverse effects. Applying the appropriate scientific rigor to characterize a biomarker assay can vary based on the type of biomarker and its role in the development process, ranging from driving internal decisions to supporting label claims. The chapter discusses a published framework that can help determine the most appropriate, fit-for-purpose method for biomarker characterization. The staining of breast or gastric cancers for human epidermal growth factor receptor 2 using immunohistochemistry is one example of a sensitive predictive biomarker. Several alternative trial designs can also evaluate the treatment effect in biomarker-defined subpopulations, even trials that only accrue positive biomarker patients. Monitoring biomarkers are measured serially to assess the status of a disease or medical condition.
