Can molecular biomarker-based patient selection in Phase I trials accelerate anticancer drug development?
Early clinical trials represent a crucial bridge between preclinical drug discovery and the especially resource-intense randomized phase III trial-the definitive regulatory hurdle for drug approval. High attrition rates and rising costs, when coupled with the extraordinary opportunities opened up by cancer genomics and the promise of personalized medicine call for new approaches in the conduct and design of phase I/II trials. The key challenge lies in increasing the odds for successful and efficient transition of a compound through the drug development pipeline. The incorporation of scientifically and analytically validated biomarkers into rationally designed hypothesis-testing clinical trials offers a promising way forward to achieving this objective. In this article, we provide an overview of biomarkers in early clinical trials, including examples where they have been particularly successful, and the caveats and pitfalls associated with indiscriminate application. We describe the use