Adapting from Phase III to Phase II at an Interim Analysis

• Activity Number: 231
• Type: Topic Contributed
• Date/Time: Monday, July 30, 2012 : 2:00 PM to 3:50 PM
• Sponsor: Biopharmaceutical Section
• Author(s): Keaven Anderson*+ and Xiaoyun (Nicole) Li
• Companies: Merck and Merck & Co.
• Keywords: adaptive design ; clinical trials ; group sequential design

Abstract

For time-to-event trials in oncology, it is often the case that the evidence that a new treatment works is based on a surrogate endpoint from a small trial. Thus, the evidence that the treatment works for a more clinically important endpoint for a definitive trial is limited. Sometimes a Phase III trial with an interim futility analysis is used to limit investment in such cases. The question becomes, if the trial stops for futility, might there still be interest in further developing the new treatment studied? Here we provide a third option to continuing or stopping a Phase III trial. We develop methods to convert a Phase III trial to a Phase II trial that provides full control of different Type I and Type II errors for Phase II and Phase III while also making the conversion rules non-binding. This strategy provides an efficient option for a new treatment in late-stage development accord