The planning and execution of clinical trials utilizing response-adaptive randomization is logistically complex. While a standardized approach to such designs is worthwhile, there are also unique challenges with each trial. Three detailed case studies are provided to illustrate the types of logistical issues that arise, as well as the decision problems coming before the data monitoring committees. Several lessons learned from these case studies are presented. These range from consideration of more extreme scenarios for trial simulation during the planning stage to formal establishment of an executive steering committee to facilitate the decision process (even for learn-phase trials).
