Katie Odem-Davis
Subjects are often randomized in clinical trials to one of two or more regimens. In the simplest case, the new experimental treatment (EXP) is evaluated for superiority relative to an inert placebo (PLA). However, when a drug has been established to be effective for treatment, use of a placebo for evaluating efficacy of the EXP may be deemed unethical and treatment is therefore compared to this “standard” treatment (STD) in an active-control trial. Showing superiority of EXP relative to STD requires techniques similar to those for EXP relative to PLA. However, when EXP has some desirable features, such as improved side-effect profile, increased ease of use, or lower cost, it may be satisfactory to show that EXP is simply not unacceptably worse than STD. In this setting, non-inferiority (NI) trials may be employed.
Methods used in NI trials are different from those for superiority trials, and there are outstanding issues unique to this field. In my talk, I will outline four main issues in NI trials, simulation designs for assessing conditions contributing to these issues, and a proposed new method to adjust for violation of a key assumption inadequately addressed by current methods used in this setting.
