5. Phase II Trial Design

  1. Guosheng Yin

Published Online: 9 JAN 2012

DOI: 10.1002/9781118183335.ch5

Clinical Trial Design: Bayesian and Frequentist Adaptive Methods

Clinical Trial Design: Bayesian and Frequentist Adaptive Methods

How to Cite

Yin, G. (2011) Phase II Trial Design, in Clinical Trial Design: Bayesian and Frequentist Adaptive Methods, John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9781118183335.ch5

Publication History

  1. Published Online: 9 JAN 2012
  2. Published Print: 19 DEC 2011

ISBN Information

Print ISBN: 9780470581711

Online ISBN: 9781118183335



  • adaptive randomization;
  • Bayesian phase II trial designs;
  • frequentist hypothesis testing;
  • Gehan's two-stage design;
  • posterior probability;
  • predictive probability;
  • Simon's two-stage designs;
  • toxicity measurements


This chapter covers many topics in phase II trial designs. For single-arm phase II trial designs, it introduces Gehan's two-stage design and Simon's optimal and minimax two-stage designs; both are cast in the frequentist hypothesis testing framework. From Bayesian perspectives, the chapter discusses how to use posterior probability and predictive probability to monitor clinical trials. With the emergence of more randomized phase II trials, Bayesian posterior predictive probabilities provide very helpful guidance for trial conduct. In addition, adaptive randomization may be incorporated to phase II designs to enhance trial ethics by assigning more patients to better treatment arms. Phase II trials often collect multiple outcomes, such as both efficacy and toxicity measurements, which could be binary or time-to-event endpoints. For each case, the chapter presents the trial design that accounts for the multivariate endpoints and also constructs the corresponding stopping rules.

Controlled Vocabulary Terms

Bayesian probability; hypothesis testing; posterior predictive distribution; posterior probability; randomization