手法を比較

	ベイジアン第II相臨床試験	フェーズII臨床試験 ― 初期有効性と用量評価
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	1990s (Thall & Simon 1994; Berry 1985–2006)	1960s–1970s (formalised in US federal drug regulation)
提唱者	Peter Thall, Richard Simon, Donald Berry (key contributors)	U.S. Food and Drug Administration / ICH E8 guidelines (institutionalised framework)
種類	Interventional clinical trial design	Interventional clinical study design
原典	Thall, P. F., & Simon, R. (1994). Practical Bayesian guidelines for phase IIB clinical trials. Biometrics, 50(2), 337–349.	Friedman, L. M., Furberg, C. D., DeMets, D. L., Reboussin, D. M., & Granger, C. B. (2015). Fundamentals of Clinical Trials (5th ed.). Springer. ISBN: 978-3319185392
別名	Bayesian phase 2 trial, Bayesian single-arm phase II study, Bayesian early-phase efficacy trial, Bayes phase II	Phase 2 trial, Phase II study, early efficacy trial, proof-of-concept trial
関連	6	6
概要	A Bayesian Phase II clinical trial applies Bayesian statistical inference to the standard Phase II objective of evaluating whether an experimental treatment shows sufficient early-phase efficacy to justify progression to a Phase III trial. By combining prior information with accumulating trial data, it enables principled interim monitoring, flexible stopping rules, and updated probability statements about treatment effect — all without the multiple-testing penalties that burden frequentist sequential designs.	A Phase II clinical trial is the second stage in the drug or intervention development pipeline, conducted after Phase I safety testing. Its primary goal is to assess whether the intervention shows preliminary efficacy signals in a relevant patient population at the dose established in Phase I, while continuing to characterise the safety and tolerability profile. Phase II trials are generally smaller than Phase III confirmatory trials and serve as critical go/no-go decision points before large-scale investment.