biostudies-literatureBofill Roig MGeneralitat de CatalunyaMinisterio de Ciencia e InnovaciónNCI NIH HHSMinisterio de Economía y Competitividad4122-4135https://www.ebi.ac.uk/biostudies/studies/S-EPMC8482791biostudies-literatureUnknown40(18)Pathologic complete response (pCR) is a common primary endpoint for a phase II trial or even accelerated approval of neoadjuvant cancer therapy. If granted, a two-arm confirmatory trial is often required to demonstrate the efficacy with a time-to-event outcome such as overall survival. However, the design of a subsequent phase III trial based on prior information on the pCR effect is not straightforward. Aiming at designing such phase III trials with overall survival as primary endpoint using pCR information from previous trials, we consider a mixture model that incorporates both the survival and the binary endpoints. We propose to base the comparison between arms on the difference of the restricted mean survival times, and show how the effect size and sample size for overall survival relyStatistics in medicineDesign of phase III trials with long-term survival outcomes based on short-term binary results.PMC8482791MTM2015‐64465‐C2‐1‐RP30 CA016672MDM‐2014‐04452017 SGR 622PID2019‐104830RB‐I00Bofill Roig MGomez Melis GShen YfalseDesign of phase III trials with long-term survival outcomes based on short-term binary results.Pathologic complete response (pCR) is a common primary endpoint for a phase II trial or even accelerated approval of neoadjuvant cancer therapy. If granted, a two-arm confirmatory trial is often required to demonstrate the efficacy with a time-to-event outcome such as overall survival. However, the design of a subsequent phase III trial based on prior information on the pCR effect is not straightforward. Aiming at designing such phase III trials with overall survival as primary endpoint using pCR information from previous trials, we consider a mixture model that incorporates both the survival and the binary endpoints. We propose to base the comparison between arms on the difference of the restricted mean survival times, and show how the effect size and sample size for overall survival rely2021-01-01T00:00:00Z2021 Aug2025-04-04T13:57:38.519Z2025-04-04T13:57:38.519ZS-EPMC84827913394235210.1002/sim.9018