Statistical analysis
SECONDARY
Categorical data were summarized as the frequency and percentage, and continuous data were summarized using the number of patients, mean, standard deviation (SD), minimum, median, and maximum. The safety analysis set comprised all patients who received tenapanor. For efficacy, the primary analysis set comprised the modified intention-to-treat population, defined as all patients who received tenapanor and whose serum phosphorus level was measured after the start of tenapanor treatment.For the primary endpoint, the incidences of all AEs and drug-related AEs that occurred or worsened after the start of tenapanor treatment were summarized using Medical Dictionary for Regulatory Activities preferred term and system organ class. Laboratory parameters and vital signs were summarized using summary statistics at each time point. The percentage of patients who achieved the key secondary endpoint was calculated, along with 95% confidence intervals (CIs). The analysis for the key secondary endpoint was performed against the threshold level of 20% and a one-sided significance level of 1.25% at the data cut-off point and final point of the treatment period. Statistical analyses were conducted using SAS version 9.4 (SAS Institute, Tokyo, Japan).The sample size was based on the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines