Statistical analysis
For Part A, Simon’s two-stage optimal design was used to determine the sample size. The null hypothesis that the true confirmed CR response rate is 16% was tested against a one-sided alternative. In the first stage, 13 patients were treated. If there were ≤2 confirmed CR response in these 13 patients, the study was to be stopped. Otherwise, 13 additional patients would be treated for a total of 26. The null hypothesis was to be rejected if ≥7 confirmed CR responses were observed in 26 patients. This design yields a Type I error rate of 0.10 and power of 0.80 when the true response rate is 35%.For Part B, a single-stage, fixed design was used. A total of 44 patients was calculated to provide ≥90% power to reject the null hypothesis that the true response rate is ≤16% when the true response rate is ≥35%, based on a one-sided binomial test with a significance level of 0.05. The null hypothesis was to be rejected if the observed CR rate is ≥25% (11 patients with CR).Unless otherwise specified, safety analyses were descriptive and performed using the all-treated population. Efficacy endpoints were analyzed using the efficacy population. DOR, PFS, and OS were analyzed using the Kaplan-Meier method.See Supplementary Materials for additional methods details.