Primary endpoint
toxicity, GI toxicity
The primary endpoint was the incidence rate of grade 2 to 4 GI toxicity independent of relatedness to the study drug within 6 months after registration. The null hypothesis of the trial was defined as bosutinib leading to GI toxicity grades 2 to 4 in ≥ 40% of the pts. All pts were asked and examined for grade 2 to 4 GI toxicity at their individual 6-month visits. Pts were evaluable, if they received at least 14 daily doses of study medication and either had a grade 2 to 4 GI toxicity at any time within the first 6 months or were observed for the complete 6 months without experiencing any grade 2 to 4 GI toxicity. To be included in the analysis, pts without previously reported grade 2 to 4 GI toxicity should have had an examination within the interval around 6 months, i.e., between > 4.5 and 9 months, but preferably between 6 and 9 months to cover at least 6 months observation time. This primary endpoint was confirmatively tested. The 95% confidence interval (CI) around the estimated rate of the primary endpoint was calculated in accordance with Clopper and Pearson [