title: Design and evaluation of multiregional trials with heterogeneous treatment effect across regions.
abstract: To speed up drug development to allow faster access to medicines for patients globally, conducting multiregional trials incorporating subjects from many countries around the world under the same protocol may be desired. Several statistical methods have been proposed for the design and evaluation of multiregional trials. However, in most of the recent approaches for sample size determination in multiregional trials, a common treatment effect of the primary endpoint across regions is usually assumed. In practice, it might be expected that there is a difference in treatment effect due to regional difference (e.g., ethnic difference). In this article, a random effect model for heterogeneous treatment effect across regions is proposed for the design and evaluation of multiregional trials. We also address consideration of the determination of the number of subjects in a specific region to establish the consistency of treatment effects between the specific region and the entire group.
authors.affiliation: Division of Biometry, Graduate Institute of Agronomy, College of Bioresource and Agriculture, National Taiwan University, Taipei, Taiwan.
authors.forename: Chi-Tian
authors.initials: CT
authors.lastname: Chen
authors.forename: H M James
authors.initials: HM
authors.lastname: Hung
authors.forename: Chin-Fu
authors.initials: CF
authors.lastname: Hsiao
mesh_terms: D000465:Algorithms; D002986:Clinical Trials as Topic / Q000379:methods / Q000706:statistics & numerical data; D006801:Humans; D015233:Models, Statistical; D015337:Multicenter Studies as Topic / Q000379:methods* / Q000706:statistics & numerical data; D016032:Randomized Controlled Trials as Topic / Q000379:methods / Q000706:statistics & numerical data; D012107:Research Design / Q000706:statistics & numerical data*; D018401:Sample Size; D016896:Treatment Outcome