| Abstract： |
When several treatment regimens are possible candidates for a large phase III study, but too few resources are available to evaluate each relative to a standard, conducting a multi-arm randomized selection trial is a useful strategy to remove inferior treatments from further consideration. When the study has a relatively quick endpoint, frequent interim monitoring of the trial becomes ethically and practically appealing. In this paper, we propose a class of sequential procedures designed to select a subset of treatments that offer clinically meaningful improvements over the control group, or to declare that no such subset exists. The proposed procedures are easy to implement, allow sequential elimination of inferior treatments and sequential recruitment of promising treatments while preserving the type I error rate, and can be applied on a flexible monitoring schedule in terms of calendar time. |