JNCI: Biomarkers should guide analysis but not treatment assignment
A randomized biomarker-stratified design, which uses the biomarker to guide analysis but not treatment assignment, provides a rigorous assessment of the utility of a potential biomarker for guiding therapy, according to a commentary published online Jan. 14 in the Journal of the National Cancer Institute.

Boris Freidlin, PhD, and colleagues at the Biometric Research Branch at the National Cancer Institute in Bethesda, Md., discussed both advantages and disadvantages of commonly used randomized trial designs, including biomarker-stratified, enrichment, and biomarker-strategy designs. Important ongoing and completed trials were used as examples by the authors and key aspects of the discussion included efficiency comparisons and special interim monitoring issues that arise because of the complexity of randomized clinical trials.

"The biomarker-stratified design maximizes the advantage of randomization by providing unbiased estimates of benefit to risk ratios across different biomarker-defined subgroups and for the entire randomly assigned population,” commented Freidlin and colleagues.

In most settings, randomized biomarker-stratified designs that use the biomarker to guide analysis but not treatment assignment should be used to obtain a rigorous assessment of biomarker clinical utility, concluded the authors.

“Clinical biomarker tests that aid in making treatment decisions will play an important role in achieving personalized medicine for cancer patients,” noted the authors.