ABSTRACT
As indicated in Chapter 7, a seamless trial design is referred to as a program that addresses study objectives within a single trial that are normally achieved through separate trials in clinical development. A two-stage (seamless) adaptive design is a seamless trial design that would use data from patients enrolled before and after the adaptation in the final analysis. Thus, a two-stage seamless adaptive design consists of two phases (stages), namely a learning (or exploratory) phase (stage 1) and a confirmatory phase (stage 2). The learning phase provides an opportunity for adaptations such as stopping the trial early due to safety and/or futility/efficacy based on accrued data at the end of the learning phase. A two-stage seamless adaptive trial design reduces lead time between the learning (i.e., the first study for the traditional approach) and confirmatory (i.e., the second study for the traditional approach) phases. Most importantly, data collected at the learning phase can be combined with those data obtained at the confirmatory phase for final analysis.
