Statistical Considerations
nausea, appetite increase, CINV, Nausea, Vomiting
SECONDARY, SENSITIVITY
The study was designed to test whether olanzapine without fosaprepitant/aprepitant was non-inferior to olanzapine with fosaprepitant/aprepitant for prevention of CINV. The primary endpoint was nausea control as defined by the proportion of patients reporting no nausea (a response of 0 in the nausea item of the Nausea and Vomiting Daily Diary/Questionnaire) in the overall (0-120 hours) period. Nausea control in the acute (0-24 hours) and the delayed (24-120 hours) periods were also reported but were only to be tested if olanzapine without fosaprepitant/aprepitant was shown to be noninferior to olanzapine with fosaprepitant/aprepitant (gatekeeping approach). Our previous studyPatient characteristics were summarized by treatment arm. Baseline symptoms were compared between arms using the Kruskal-Wallis test. The primary endpoint of nausea control and secondary endpoints including complete response, undesired appetite increase, and undesired sedation rates were summarized by treatment arm using frequency and proportion. The differences in these rates between treatment arms were estimated (along with 95% confidence interval) and tested using normal approximation of the binomial distribution. Sensitivity analyses of the primary and secondary endpoints using repeated measurement and growth curve models to account for time trend were conducted. Except for the primary endpoint (with a one-sided test of non-inferiority), all confidence intervals and p-values for other endpoints reported were 2 sided. Data collection and statistical analyses were conducted by the Alliance Statistics and Data Management Center. All analyses were conducted using the SAS software version 9.4 on a database locked on January 7, 2022. Data quality was ensured by review of data by the Alliance Statistics and Data Management Center and by the study chairperson following Alliance policies.This phase III trial was monitored by the Alliance Data and Safety Monitoring Board, a standing committee composed of individuals from within and outside of the Alliance.