A Two-Stage Adaptive Targeted Clinical Trial Design for Biomarker Performance-Based Sample Size Re-Estimation
- 157 Downloads
Biomarker-directed targeted clinical trial is aimed at developing pharmaceutical agents for a targeted patient subpopulation sharing a specific disease etiology. Biomarker plays a key role in patient enrichment for targeted trials. Biomarker performance substantially impacts heterogeneity of a targeted study population and consequently trial efficiency, statistical power, information accumulation, and early stopping decision-making (Simon and Maitournam in Clinical Cancer Res 10:6759-6763, 2004; Maitournam and Simon in Stat Med 24:329-339, 2005; Gao et al. in Contemp Clin Trials 42:119-131, 2015). Hence, accurate assessment of biomarker performance is crucial to sample size calculation in planning of targeted trials. However, prior knowledge of biomarker performance is often limited at the planning stage due to inadequacy of biomarker validation, differences between study populations in demographic characteristics and trial settings, etc. Under this circumstance, adaptive design would be useful in updating biomarker performance and re-estimating sample sizes when a targeted trial is ongoing. In this paper, we propose a two-stage adaptive design that provides flexibility in biomarker performance-based sample size adaption for targeted trials. The design can facilitate a targeted trial to achieve planned statistical power by re-assessment of actual biomarker performance and subsequent sample size adaption while preserving desired type-1 error.
KeywordsPositive Predictive Value Conditional Power Initial Sample Size Sample Size Adaption Patient Enrichment
- 5.Lan KKG, Trost DC (1997) Estimation of parameters and sample size re-estimation. In: Proceedings of the Biopharmaceutical Section, American Statistical Association, pp 48–51Google Scholar
- 10.U.S. Food and Drug Administration (2010) Guidance for industry: adaptive design clinical trials for drugs and biologics (draft guidance)Google Scholar
- 11.European Medicines Agency (2007) Reflection paper on methodological issues in confirmatory clinical trials planned with an adaptive designGoogle Scholar