Bayesian and Adaptive Clinical Trial Simulation and Monitoring R package AdaptiveTrialsR version 0.1.2 Provides tools for simulating, monitoring, and evaluating Bayesian and adaptive clinical trial designs with binary outcomes. The package includes methods for trial simulation, posterior and predictive probability monitoring, adaptive randomization, Bayesian treatment-effect estimation, dose-finding designs, two-stage phase II trial designs, group sequential monitoring, operating-characteristic evaluation, interim analyses, and decision-support procedures. The methodological foundation includes the two-stage phase II design described by Simon (1989) <doi:10.1016/0197-2456(89)90015-9>. Software Imports: stats, utils, dplyr, ggplot2, rlang Suggests: testthat (>= 3.0.0) Muhammad Zahir Khan <zahirstat007@gmail.com> Comprehensive R Archive Network (CRAN) Muhammad Zahir Khan [aut, cre] MIT + file LICENSE (https://CRAN.R-project.org/package=AdaptiveTrialsR/LICENSE) 2026-07-30 application/tgz https://CRAN.R-project.org/package=AdaptiveTrialsR doi:10.32614/CRAN.package.AdaptiveTrialsR