Optimizing Pediatric Dose Finding: A Phase I/II Design Integrating Adult Data

Precision dose selection in pediatric trials is imperative given children’s distinct profiles, yet constrained by ethical barriers and recruitment challenges that could be strategically mitigated through adult trial data integration. To address the limitations of existing methods, we propose the pp-BOIN12 and pp-TITE-BOIN12 designs based on the Power prior framework to identify optimal biological dose (OBD) and address delayed outcomes. These designs adaptively quantify dose-level similarity between adult and pediatric cohorts using Hellinger distance to calibrate real-time borrowing weights. Numerical simulations demonstrate that pp-BOIN12 improves the percentage of correct OBD selection while reducing patient assignments to doses above maximum tolerated dose (MTD). pp-TITE-BOIN12 maintains comparable accuracy with minimal performance degradation while significantly shortening trial duration. This work provides an adaptive and safe method for incorporating adult data into pediatric extrapolation trials.