RegionSizeR- A Novel App for Regional Sample Size Planning in MRCTs

Area of Science:

• Clinical Trials
• Biostatistics
• Pharmaceutical Development

Background:

• Multi-regional clinical trials (MRCTs) require careful sample size planning to ensure treatment effect consistency across diverse regions.
• Existing methods often rely on consistency probability, but regional enrollment characteristics necessitate tailored approaches.
• ICH E17 guidelines emphasize preserving a proportion of the overall treatment effect in regional planning.

Purpose of the Study:

• To develop a user-friendly tool for efficient and harmonized sample size planning in MRCTs.
• To provide a simulation-based application supporting discussions on sample size allocation strategies.
• To implement the treatment effect preservation method outlined in ICH E17.

Main Methods:

• Development of RegionSizeR, an interactive, web-based R shiny application.
• Simulation-based approach for sample size calculations and allocation.
• Accommodation of various endpoint types (continuous, binary, time-to-event) and trial designs (superiority, non-inferiority, MCP-Mod).

Main Results:

• RegionSizeR offers a comprehensive platform for regional sample size planning in MRCTs.
• The application supports diverse clinical trial designs and endpoint types.
• Independent testing confirmed the app's validity with results showing discrepancies of no more than 1% across various scenarios.

Conclusions:

• RegionSizeR facilitates informed decision-making for sample size allocation in MRCTs.
• The tool promotes harmonized planning by considering regional specifics and ICH E17 principles.
• This application serves as a valuable resource for optimizing MRCT design and ensuring treatment effect consistency.