Statistical Methods
PD
DISEASE, SECONDARY
The power analysis and sample size estimation were completed using the Bayesian adaptive trial design method. We modeled the probability of ORR using Beta distributions. The prior distribution is Beta(0.1, 0.9), which is fairly pessimistic; the expected value is 0.1, reflecting the response rate based on previous experiences. We estimated the ORR using the posterior distribution and reported its median and 90% credible interval (see protocol for details). It was predetermined that the trial would be terminated if there was a lack of response, that is, the probability of the ORR being greater than 0.1 was 50% or less. Because the ORR in the trial was zero, the trial was terminated. The SD rate and the progressive disease (PD) rate were reported, and the 90% credible intervals were estimated using the posterior distribution. SD was defined as lack of progression at first restaging after two cycles.For secondary objectives, the median PFS and OS were estimated using Kaplan–Meier estimate with 95% confidence intervals (CI). The CIs were based on Greenwood formula for variance. Possible risk factors for PFS and OS of WHO grade and 