40: Jumping Hurdles: Interim Analyses for Funding Decisions

In episode 40 of "In the Interim…", Dr. Scott Berry examines the statistical, operational, and behavioral challenges of using interim analyses as triggers for funding in adaptive and seamless Phase II/III clinical trials. The episode presents a typical hypothetical scenario for rare disease drug development, contrasting conventional two-stage development with a seamless design and highlighting efficiency gains in sample size, patient allocation, and trial duration. Scott details the construction of administrative (financial) interim analyses, underscoring their distinction from futility analyses and their role in funding decisions when complete funding is not secured upfront. He addresses FDA operational bias concerns, emphasizing blinding and limiting information sharing to protect trial integrity. Finally, the episode focuses on developing objective interim funding criteria—using Bayesian predictive probability and assurance—and on leveraging illustrative simulation outputs and sample datasets to bridge the “I’ll know it when I see it” divide between scientists and funders. Practical, empirical, and tailored to real funding barriers in clinical research.

Key Highlights

• Statistical structure and efficiency of seamless Phase II/III trial designs

• Administrative (financial) interim analysis setup as funding decision triggers, distinct from futility analyses

• FDA operational bias guidance and requirements for trial blinding

• Predictive probability and assurance as objective interim criteria

• Sample data and simulation outputs to facilitate stakeholder alignment