เปรียบเทียบวิธี

	การทดลองทางคลินิกระยะที่ II	การศึกษาทางคลินิกระยะที่ 1
สาขาวิชา	ระบาดวิทยา	ระบาดวิทยา
ตระกูล	Process / pipeline	Process / pipeline
ปีกำเนิด	1960s–1970s (formalised in US federal drug regulation)	1960s (formal regulatory framework established ~1963–1970s)
ผู้ริเริ่ม	U.S. Food and Drug Administration / ICH E8 guidelines (institutionalised framework)	Regulatory and clinical pharmacology community; formalized in U.S. FDA IND regulations (1963) and ICH guidelines
ประเภท	Interventional clinical study design	Interventional clinical study design
แหล่งต้นตำรับ	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	Storer, B. E. (1989). Design and analysis of phase I clinical trials. Biometrics, 45(3), 925–937.
ชื่อเรียกอื่น	Phase 2 trial, Phase II study, early efficacy trial, proof-of-concept trial	Phase 1 trial, first-in-human study, FIH study, dose-escalation study
ที่เกี่ยวข้อง	6	6
สรุป	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.	A Phase I clinical trial is the first stage of human testing for a new drug, biologic, or intervention. Its primary objective is to evaluate safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) rather than therapeutic efficacy. Small cohorts of participants — typically healthy volunteers or patients with advanced disease — receive sequentially increasing doses to identify the maximum tolerated dose (MTD) and the dose-limiting toxicities (DLTs) that define the boundary for subsequent trials.