RPACT Cloud

Interactive Platform for Statistical Methods in Clinical Research

Friedrich Pahlke

RPACT

June 24, 2026

A Journey in Trial Design Software

  • My connection to Takeda goes back to my ADDPLAN years.
  • At that time, I worked with Gernot Wassmer on the further development of ADDPLAN — a legacy software that runs only on Windows.
  • Gernot originally invented and developed ADDPLAN, and some of you may still be familiar with it.
  • In my role, I also had insight into how ADDPLAN was used across the pharmaceutical industry, including at Takeda.
  • For me, this was the beginning of a long journey: more than 20 years of working at the interface of adaptive design methodology and user-friendly software implementation.
  • With rpact and now RPACT Cloud, we continue this work in a modern, open, validated, and web-based environment.

RPACT Cloud

Why RPACT Cloud?

What are the advantages of using RPACT Cloud instead of directly using the R package rpact or other software, e.g., ADDPLAN or East?

  • User-friendly graphical user interface: Users do not need to write R code, but can point and click to design their trial
    • Provides an easy entry to rpact
    • Starting point for your R Markdown or Quarto reports
    • Helpful to learn/demonstrate the usage of rpact in a user friendly and intuitive way
  • Web-based: No local installation required, accessible from any device with internet access
  • Free demo available: At rpact.cloud, users can try out RPACT Cloud for free

Why RPACT Cloud? (cont’d)

  • Company installation: Companies can install RPACT Cloud on their own servers, ensuring data security and compliance with internal policies
  • Cost-effective: Installation license with a flat rate per company, no per-user fees, and no hidden costs for updates or included support
  • Continuous development: We are constantly developing and improving RPACT Cloud based on user feedback and the latest methodological research
  • Fully validated: License includes installation qualification tests for the GUI (Shiny test suite), adding on top of the rpact package validation

What can RPACT Cloud be used for?

RPACT Cloud: Trial Designs

  • Fixed sample design
  • Group sequential designs
  • Adaptive designs using the inverse normal and Fisher’s combination test, and conditional error rate principle

RPACT Cloud: Sample Size and Power Calculation

for

  • testing means (continuous endpoint)
  • testing rates (binary endpoint)
  • survival trials with flexible recruitment and survival time options
  • testing rates for count data

RPACT Cloud: Simulation Tool

for means, rates, survival data, and count data

  • Assessment of adaptive sample size/event number recalculation strategies
  • Assessment of treatment selection strategies in multi-arm trials
  • Assessment of population selection strategies in enrichment designs (planned for late 2026)

\(\rightarrow\) rpact useful for conducting innovative designs and flexible simulations in clinical trial planning

RPACT Cloud

RPACT Cloud – Basics

RPACT Cloud – Explore Parameter Levels

RPACT Cloud – Settings

RPACT Cloud – Quick Start Menu

RPACT Cloud – Design Tabs

RPACT Cloud – Getting Help

RPACT Cloud – Copy And Paste

RPACT Cloud – Output Options

RPACT Cloud – Reporting

RPACT Cloud – Export

RPACT Cloud – Plotting

RPACT Cloud – Output Table

RPACT Cloud – Design Comparison

Outlook to Future Developments

Future of RPACT Cloud

In the near future you will see in RPACT Cloud:

  • Count data simulations, complementing the currently available sample size and power functionality
  • Enrichment designs, which are currently not yet available and are planned for implementation by the end of 2026
  • Exploration of an integrated AI chat interface, potentially powered by the upcoming “RPACT Code” technology
  • A gradual transition from an rpact-focused GUI towards a flexible platform for clinical trial design
  • Future support for additional statistical methodologies beyond rpact, such as graphical multiple testing procedures

New Edition of the Reference Book

  • Group Sequential and Confirmatory Adaptive Designs in Clinical Trials by Gernot Wassmer and Werner Brannath
  • Second Edition (Springer, 2025) — published on September 24, 2025
  • Now featuring numerous rpact R code examples demonstrating the methods implemented in the package
  • For more information, visit: link.springer.com/book/10.1007/978-3-031-89669-9

Summary

  • RPACT Cloud is our web-based graphical user interface for rpact, with a focus on ease of use and accessibility
  • We are continuously developing and improving our software based on user feedback and the latest methodological research
  • This year we are developing “RPACT Code” (working title), a next-generation agentic AI system that helps statisticians design clinical trials using natural language, while ensuring that all results are computed deterministically and reproducibly in R

Thank You