"How New Knowledge about Cancer Is Changing Clinical Trials"

Over the last two decades, biomedical researchers have begun to unravel cancer’s immense complexity, drilling down to the molecular level to better understand the genetic and biological changes that drive how cancers develop, grow, and spread. Today, researchers are able to sequence the genome of an individual patient’s cancer more quickly and more cheaply than ever before, making precision medicine possible.

This greater understanding of cancer and how tumors behave at the molecular level has allowed scientists to develop a new generation of targeted drugs and immune-based therapies, identify biomarkers that can be used to guide therapy and select patients who are most likely to respond to a drug, and develop novel strategies to detect difficult-to-treat cancers early.

The practice of clinical trials is evolving to keep pace with these advances in the scientific understanding of cancer. Already, for example, investigators are conducting fewer very large trials in which all patients, regardless of the underlying biology of their cancers, are randomly assigned to receive the experimental or control treatment. These large trials often require large numbers of participants to detect an effect because, often, too few patients respond to the experimental therapy to draw a definitive conclusion.

NCI is adapting its clinical trials programs to build on new research insights that target molecular alterations and only test the experimental therapy in the selected population. This approach can increase the speed and efficiency of clinical trials, as only the patients most likely to benefit are included in the trial.