Superiority, equivalence and non-inferiority trials

ICH E9 (1998) Note for Guidance on Statistical Principles for Clinical Trials  

Typically, later phase trials tend to have the confirmatory elements while the earlier phase studies proof of concept, dose-finding etc. are viewed as exploratory. Indeed an alternative word for confirmatory is pivotal. It is the confirmatory elements of our trials that provide the pivotal information from a regulatory perspective. 

Usually it is the primary endpoint(s) that provides the basis of the confirmatory claims and exploratory aspects are relegated to the secondary (or exploratory) endpoints. 

A clear distinction should also be made between superiority, equivalence and 

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