This article discusses futility analyses for the MCP-Mod methodology. Formulas are derived for calculating predictive and conditional power for MCP-Mod, which also cover the case when longitudinal models are used allowing to utilize incomplete data from patients at interim. A simulation study is conducted to evaluate the repeated sampling properties of the proposed decision rules and to assess the benefit of using a longitudinal versus a completer only model for decision making at interim. The results suggest that the proposed methods perform adequately and a longitudinal analysis outperforms a completer only analysis, particularly when the recruitment speed is higher and the correlation over time is larger. The proposed methodology is illustrated using real data from a dose-finding study for severe uncontrolled asthma.

翻译：本文探讨了MCP-Mod方法的无效性分析。研究推导了适用于MCP-Mod的预测效能与条件效能计算公式，这些公式同样适用于采用纵向模型以利用期中分析时患者不完整数据的情况。通过模拟研究评估了所提决策规则的重抽样特性，并比较了在期中决策时使用纵向模型与仅使用完成者模型的优势。结果表明，所提方法表现良好，且纵向分析优于仅基于完成者的分析，尤其在招募速度较快和时间相关性较强时更为明显。本文通过一项严重未控制哮喘剂量探索研究的真实数据对所提方法进行了实例演示。