The newly proposed guidelines are designed to be applicable across a spectrum of confirmatory clinical studies, encompassing chemical drugs, biological products, and traditional Chinese medicine (TCM). They also hold significant value for exploratory research endeavors.
Adopting an adaptive design should be predicated on considerations of rationality, integrity, and feasibility. The draft outlines six prevalent adaptive designs, each with its own set of strategic considerations:
- Group Sequential Design: Involves planning for one or more interim analyses with subsequent decisions based on the outcomes. The timing of these interim analyses is critical.
- Sample Size Re-estimation: Refines the sample size as the trial progresses, in line with the data accrued and pre-specified interim analysis plans.
- Two-Stage Seamless Adaptive Design: Divides the trial into two phases, with an interim analysis concluding the first stage, followed by modifications to the second phase based on pre-set criteria. Common variations include I/II (exploratory) and II/III (confirmatory) seamless adaptive designs.
- Adaptive Enrichment Design: Post Phase I, the target population is recalibrated according to interim analysis and preset criteria, guiding the determination of the target population in the subsequent phase.
- Master Protocol with Adaptive Designs: Incorporates one or more adaptive design elements within a master protocol, facilitating multiple adaptive adjustments throughout the study.
- Multiple Adaptive Design: Employs two or more adaptive adjustment methods within a single study design.
