biostudies-literatureWu JNational Cancer InstituteAmerican Lebanese Syrian Associated CharitiesNCI NIH HHS1235-1248https://www.ebi.ac.uk/biostudies/studies/S-EPMC9502026biostudies-literatureUnknown20(6)For the cancer clinical trials with immunotherapy and molecularly targeted therapy, time-to-event endpoint is often a desired endpoint. In this paper, we present an event-driven approach for Bayesian one-stage and two-stage single-arm phase II trial designs. Two versions of Bayesian one-stage designs were proposed with executable algorithms and meanwhile, we also develop theoretical relationships between the frequentist and Bayesian designs. These findings help investigators who want to design a trial using Bayesian approach have an explicit understanding of how the frequentist properties can be achieved. Moreover, the proposed Bayesian designs using the exact posterior distributions accommodate the single-arm phase II trials with small sample sizes. We also proposed an optimal two-stage aPharmaceutical statisticsBayesian single-arm phase II trial designs with time-to-event endpoints.PMC9502026P30 CA177558P30CA177558Pan HWu JHsu CWfalseBayesian single-arm phase II trial designs with time-to-event endpoints.For the cancer clinical trials with immunotherapy and molecularly targeted therapy, time-to-event endpoint is often a desired endpoint. In this paper, we present an event-driven approach for Bayesian one-stage and two-stage single-arm phase II trial designs. Two versions of Bayesian one-stage designs were proposed with executable algorithms and meanwhile, we also develop theoretical relationships between the frequentist and Bayesian designs. These findings help investigators who want to design a trial using Bayesian approach have an explicit understanding of how the frequentist properties can be achieved. Moreover, the proposed Bayesian designs using the exact posterior distributions accommodate the single-arm phase II trials with small sample sizes. We also proposed an optimal two-stage a2021-01-01T00:00:00Z2021 Nov2025-04-18T20:52:12.638Z2025-04-07T08:56:04.989ZS-EPMC95020263408576410.1002/pst.2143