Two-Stage Designs with Additional Futility Tests for Phase II Clinical Trials with Heterogeneous Patient Populations

• Activity Number: 130
• Type: Contributed
• Date/Time: Monday, August 2, 2010 : 8:30 AM to 10:20 AM
• Sponsor: Biopharmaceutical Section
• Author(s): Myron N. Chang*+ and Sin-Ho Jung
• Companies: University of Florida and Duke University
• Keywords: futility test ; efficacy test ; Type I error ; power ; two-stage test

Abstract

In some Phase II clinical trials, the study therapy may be inefficacious in some subgroups, but efficacious in the remaining subgroups. In this article, we propose two-stage testing procedures. The futility test will be performed within each subgroup. If there is strong evidence that the study therapy is inefficacious in some subgroups, these subgroups will be excluded for further consideration and then the efficacy test will be performed across the remaining subgroups. Our numerical studies show that with proper designs, the proposed testing procedure has a power similar to that without futility tests under the alternative hypothesis that the study therapy is efficacious in all subgroups, and simultaneously, the proposed testing procedure detects inefficacious subgsubgroups with a moderate or high probability when true response rates in tthese subgroups are low.