ASCO20: Bosutinib for Patients With TKI-Intolerant CML
Posted: Monday, June 1, 2020
The results of the BYOND study support the use of bosutinib in patients with Philadelphia chromosome–positive chronic myeloid leukemia (CML) that is resistant or intolerant to prior tyrosine kinase inhibitors (TKIs), according to analyses presented during the ASCO20 Virtual Scientific Program (Abstract 7551). “Despite being intolerant to all prior therapies, more than 50% of patients in the overall intolerant cohort remained on bosutinib treatment at the data cutoff, and more than 80% achieved or maintained a major molecular response,” stated Susanne Saussele, MD, of Heidelberg University, Mannheim, Germany, and colleagues.
The ongoing phase IV study included 73 patients with Philadelphia chromosome–positive CML in chronic phase who entered the study with intolerance to all prior TKIs. A total of 29 patients had received 1 prior TKI, 26 received 2 prior TKIs, and 18 received 3 prior TKIs. The overall median treatment duration was 25.3 months.
The survival rate at 2 years was 97.2%, and a major molecular response was achieved in 89.7%, 84.6%, and 66.7% of patients previously treated with one, two, and three lines of TKI therapy, respectively. At the data cutoff, approximately half of patients (53.4%) were still receiving bosutinib therapy.
Treatment with bosutinib was discontinued in 28.8% of patients due to adverse events. The most common treatment-emergent adverse events were diarrhea (87.7%) and nausea (43.8%). Grade 3 or 4 treatment-emergent adverse events included diarrhea (16.4%), increased alanine aminotransferase levels (19.2%), and increased lipase levels (12.3%). In all, 84.9% of patients had at least one dose reduction, and 83.6% had at least one dose interruption due to adverse events.
Disclosure: For full disclosures of the study authors, visit coi.asco.org.