Adaptive Randomization for Clinical Trials

Abstract

In February 2010, the U.S. Food and Drug Administration (FDA, 2010) drafted guidance that discusses the statistical, clinical, and regulatory aspects of various adaptive designs for clinical trials. An important class of adaptive designs is adaptive randomization, which is considered very briefly in subsection VI.B of the guidance. The objective of this paper is to review several important new classes of adaptive randomization procedures and convey information on the recent developments in the literature on this topic. Much of this literature has been focused on the development of methodology to address past criticisms and concerns that have hindered the broader use of adaptive randomization. We conclude that adaptive randomization is a very broad area of experimental design that has important application in modern clinical trials.

Key Words:

• Adaptive designs
• Delayed response
• Optimal allocation
• Sequential analysis

ACKNOWLEDGMENTS

The views of the second author (Oleksandr Sverdlov) expressed herein do not necessarily represent the views or practices of the author's employer or any other party.

Feifang Hu's research was partial supported by DMS-0907297 and DMS-0906661 from the National Science Foundation (USA). William F. Rosenberger's research was supported by National Science Foundation grant DMS-0904253 under the 2009 American Reinvestment and Recovery Act.