Regulatory Issues in use of Biomarkers in Oncology Trials

In the current era of personalized medicine, there has been an increased interest in biomarkers as a classifier for patient risk cohorts as well as a predictor of success for a therapeutic intervention. They hold promise to better screen patients who may or may not benefit from a particular treatment, but may experience toxicity inherent in oncology treatments. However, in general the classifier biomarkers are identified in post-hoc subgroup analyses. In this article we discuss the challenges in ascertaining true positive results from such post-hoc analyses.