手法を比較

	フェーズII臨床試験 ― 初期有効性と用量評価	適応的無作為化比較試験
分野	疫学	疫学
系統	Process / pipeline	Process / pipeline
提唱年	1960s–1970s (formalised in US federal drug regulation)	Late 1990s–2000s (widespread adoption post-2010)
提唱者	U.S. Food and Drug Administration / ICH E8 guidelines (institutionalised framework)	Donald Berry and colleagues; formalized by FDA guidance in 2010 and 2019
種類	Interventional clinical study design	Experimental clinical trial design
原典	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	Berry, D. A. (2006). Bayesian clinical trials. Nature Reviews Drug Discovery, 5(1), 27–36.
別名	Phase 2 trial, Phase II study, early efficacy trial, proof-of-concept trial	adaptive RCT, adaptive trial design, response-adaptive randomization trial, adaptive clinical trial
関連	6	6
概要	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.	An adaptive randomized clinical trial (adaptive RCT) is a prospective experimental study that uses pre-specified rules to modify one or more trial aspects — such as sample size, allocation ratios, or treatment arms — based on accumulating data collected during the trial itself, while maintaining statistical validity and integrity of the study.