Aim: We develop a subgroup selection procedure using both prognostic and predictive biomarkers to identify four patient subpopulations: low- and high-risk responders, and low- and high-risk nonresponders.
Methods: We utilize three regression models to identify three sets of biomarkers: S, prognostic biomarkers; T, predictive biomarkers; and U, prognostic and predictive biomarkers. The prognostic signature C(S) combines with a predictive signature, either C(T) or C(U), to develop two procedures C(S,T) and C(S,U) for identification of four subgroups.
Results: Simulation experiment showed that proposed models for identifying the biomarker sets S and U performed well, as did the procedure C(S,U) for subgroup identification.
Conclusion: The proposed model provides more comprehensive characterization of patient subpopulations, and better accuracy in patient treatment assignment.
Keywords: biomarker identification; clinical trial; interaction test; predictive classifiers; subgroup selection; tailored therapy.