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arXiv · 2007.04951

Adding experimental treatment arms to Multi-Arm Multi-Stage platform trials in progress

Thomas Burnett·Franz König·Thomas Jaki
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Abstract

Multi-Arm Multi-Stage (MAMS) platform trials are an efficient tool for the comparison of several treatments. Suppose we wish to add a treatment to a trial already in progress, to access the benefits of a MAMS design. How should this be done? The MAMS framework requires pre-planned options for how the trial proceeds at each stage in order to control the family-wise error rate. Thus, it is difficult to make both planned and unplanned design modifications. The conditional error approach is a tool that allows unplanned design modifications while maintaining the overall error rate. In this work, we use the conditional error approach to allow adding new arms to a MAMS trial in progress. We demonstrate the principles of incorporating additional hypotheses into the testing structure. Using this framework, we show how to update the testing procedure for a MAMS trial in progress to incorporate additional treatment arms. Simulations illustrate the possible operating characteristics of such procedures using a fixed rule for how and when the design modification is made.

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Thomas Burnett, Franz König, Thomas Jaki. 2020-07-09. Adding experimental treatment arms to Multi-Arm Multi-Stage platform trials in progress. https://arxiv.org/abs/2007.04951

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