Quantitative Considerations for Enrichment Clinical Trial Implementation: Marker Prevalence, Effect Size, Diagnostic Assay Performance, Sample Size, and Beyond

• Activity Number: 163
• Type: Topic Contributed
• Date/Time: Monday, August 5, 2013 : 10:30 AM to 12:20 PM
• Sponsor: Biopharmaceutical Section
• Author(s): Ray Liu*+
• Companies: Columbia
• Keywords: enrichment trial ; biomarker ; sample size ; diagnostic

Abstract

In oncology trials, it has become more and more important to use biomarkers to select patients who are most likely to respond to the treatment under investigation. The main benefit of such enrichment trial design is the smaller sample size. Many factors influence the needed sample size, including the effect size of the treatment in both marker positive and marker negative populations, marker prevalence, and the quality of the diagnostic assay to measure the biomarker for clinical use. This work quantitatively demonstrates how these factors relate to each other, and how they affect sample size, trial cost, and recruitment timeline. The information is critical to facilitate decision-making in the planning stage of clinical trials.