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Published on: September 20, 2019
An adaptive group sequential design for phase II/III clinical trials that select a single treatment from several
Patrick J Kelly1, Nigel Stallard, Susan Todd
1Medical and Pharmaceutical Statistics Research Unit, The University of Reading, UK. patrick.kelly@reading.ac.uk
Abstract:
There is increasing interest in combining Phases II and III of clinical development into a single trial in which one of a small number of competing experimental treatments is ultimately selected and where a valid comparison is made between this treatment and the control treatment. Such a trial usually proceeds in stages, with the least promising experimental treatments dropped as soon as possible. In this paper we present a highly flexible design that uses adaptive group sequential methodology to monitor an order statistic. By using this approach, it is possible to design a trial which can have any number of stages, begins with any number of experimental treatments, and permits any number of these to continue at any stage. The test statistic used is based upon efficient scores, so the method can be easily applied to binary, ordinal, failure time, or normally distributed outcomes. The method is illustrated with an example, and simulations are conducted to investigate its type I error rate and power under a range of scenarios.
Insights
This study introduces a flexible adaptive trial design for efficiently selecting the best experimental treatment by dropping less promising options early. This method ensures valid comparisons with control treatments across various outcome types.
Area of Science:
- Clinical trial methodology
- Biostatistics
- Drug development
Background:
- Increasing interest in integrating Phase II and III clinical trials.
- Need for efficient methods to select superior experimental treatments early.
- Requirement for valid comparisons between selected treatments and controls.
Purpose of the Study:
- To present a flexible adaptive group sequential design for multi-stage clinical trials.
- To enable the selection of one experimental treatment from multiple candidates.
- To ensure valid comparisons with a control treatment throughout the trial.
Main Methods:
- Utilizes adaptive group sequential methodology to monitor an order statistic.
- Employs efficient scores for the test statistic, allowing application to diverse outcome types.
- Design accommodates variable stages, initial number of treatments, and ongoing treatment selection.
Main Results:
- The proposed design is highly flexible regarding trial stages and treatment numbers.
- The method is applicable to binary, ordinal, failure time, and normally distributed outcomes.
- Simulations confirm the design's control of type I error rate and power across scenarios.
Conclusions:
- The presented adaptive design offers a robust and flexible approach for combined Phase II/III clinical trials.
- This methodology facilitates efficient selection of promising treatments while maintaining statistical validity.
- The design's adaptability and broad applicability to different outcome measures enhance its utility in drug development.
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