Adaptive designs for dose-finding studies based on sigmoid Emax model.
We propose an adaptive procedure for dose-finding in clinical trials when the primary efficacy endpoint is continuous. We model the mean of the efficacy endpoint, given the dose, as a four-parameter logistic function. The efficacy endpoint at each dose is distributed according to either a normal or a gamma distribution. We consider the cases of fixed variance and fixed coefficient of variation assuming them to be both known and unknown. The analytic formulae for the Fisher information matrix are obtained, which are used to build the locally and adaptive D-optimal designs.
Dragalin
Vladimir
V
Wyeth Research, Collegeville, Pennsylvania 19426, USA.
Hsuan
Francis
F
Padmanabhan
S Krishna
SK
D002986:Clinical Trials as Topic / Q000379:methods* / Q000706:statistics & numerical data; D003198:Computer Simulation; D004305:Dose-Response Relationship, Drug; D006801:Humans; D016013:Likelihood Functions; D015233:Models, Statistical; D012107:Research Design