Introduction
nausea, ELN recommendations, diarrhea, toxicity, vomiting, gastrointestinal toxicities
SECONDARY, BLAST CRISIS
Bosutinib is a second-generation TKI approved in Europe in 2013 for CML-chronic phase (CP), accelerated phase (AP), and blast crisis (BC). The licensed starting dose of bosutinib has recently been defined to be 400 g QD for first [The most frequent side effects of bosutinib treatment are gastrointestinal toxicities. In the BYOND trial, 87.7% suffered from all grade diarrhea (comprising 16% grade 3/4), 39.9% from nausea, and 32.5% from treatment-emergent vomiting mostly in the initial days of treatment [Generally speaking, gastrointestinal side effects are very common across all bosutinib trials but typically remain manageable [Preservation of efficacy following secondary dose reductions of bosutinib (after initiation of treatment with the approved standard dose) has mostly been retrospectively addressed within the study populations assessed showing similar efficacy even in lower dosages [The purpose of the current phase 2 study was to evaluate whether a new therapeutic scheduling approach, termed “bosutinib step-in dosing regimen,” might be able to decrease early-occurring GI toxicity while maintaining optimal efficacy according to ELN recommendations [