Some essential considerations in the design and conduct of non-inferiority trials.

Publication Type:

Journal Article


Clinical trials (London, England), Volume 8, Issue 4, p.432-9 (2011)


2011, Center-Authored Paper, Human Biology Division, September 2011, Vaccine and Infectious Disease Division


Suppose a standard therapy (Standard) has been established to provide a clinically important reduction in risk of irreversible morbidity or mortality. In that setting, the safety and efficacy of an experimental intervention likely would be assessed in a clinical trial providing a comparison with Standard rather than a placebo arm. Such a trial often is designed to assess whether the efficacy of the experimental intervention is not unacceptably worse than that of Standard, and is called a non-inferiority trial. Formally, the non-inferiority trial usually is designed to rule out a non-inferiority margin, defined as the minimum threshold for what would constitute an unacceptable loss of efficacy.