One- and two-stage designs for stratified phase II clinical trials

A global one-sample test for response rates for stratified phase II clinical trials is proposed. Such a test is analogous to that of a stratified log-rank test for time-to-event data. Both one- and two-stage tests are developed, and conditional and unconditional approaches are introduced in each case, where the conditional approach involves conditioning on the observed samples sizes within the strata. The methodology generates samples sizes and stopping boundaries that provide designs with the desired power and type I error probability. These methods are useful for designing stratified phase II clinical trials. An application to a Children's Oncology Group phase II clinical trial in relapsed neuroblastoma patients is presented.