Introduction to Adaptive Designs for Clinical Trials

This guide provides an introduction to adaptive designs for clinical trials, a method that allows for modifications to trial designs based on accumulating data. It contrasts adaptive designs with fixed-sample designs (FSDs), which have predetermined sample sizes. The document outlines the advantages of adaptive designs, including increased statistical efficiency and ethical considerations, such as reducing the number of participants assigned to ineffective treatments. It also discusses the complexities involved in implementing adaptive designs, including the need for timely data reporting and the potential for larger maximum sample sizes. The guide categorizes popular adaptive design methods, including group sequential designs, sample-size modification methods, adaptive randomization, treatment-arm modification, and adaptive enrichment designs. Each category is briefly explained, highlighting their specific applications and benefits in clinical trials. The document emphasizes that adaptive designs are a topic of ongoing research and are not a one-size-fits-all solution for clinical trial challenges.