Patient-reported outcomes in the phase 3 BFORE trial of bosutinib versus imatinib for newly diagnosed chronic phase chronic myeloid leukemia

Background: In the phase 3 BFORE trial (NCT02130557), treatment with bosutinib resulted in a significantly higher major molecular response rate at 12months versus imatinib in the modified intent-to-treat (mITT) population of patients with newly diagnosed chronic phase chronic myeloid leukemia (CP CML). Assessment of patient-reported outcomes (PROs) was an exploratory objective. Methods: Patients with newly diagnosed CP CML were randomized 1:1 to receive once-daily bosutinib 400mg or imatinib 400mg as first-line therapy. Patients completed the Functional Assessment of Cancer Therapy-Leukemia (FACT-Leu) and EuroQoL-5 Dimensions (EQ-5D) questionnaires at baseline, every 3 months for the first 24 months of treatment, every 6 months thereafter, and at treatment completion. We report PRO results at month 12 in the mITT population (bosutinib: n = 246; imatinib: n = 241). Results: Mean FACT-Leu combined and subscale scores were similar at baseline in the bosutinib and imatinib arms; at month 12, all scores demonstrated improvement or maintenance of health-related quality of life (HRQoL) in both treatment arms. Repeated-measures mixed-effects models showed no significant difference between bosutinib and imatinib for any FACT-Leu score. Functional health status, as measured by EQ-5D, also demonstrated improvement or maintenance with bosutinib and imatinib at month 12. Conclusions: Similar improvements in PROs compared with baseline were seen after 12 months of treatment with first-line bosutinib or imatinib in the BFORE trial. Newly diagnosed patients with CP CML receiving bosutinib or imatinib can preserve or improve HRQoL during treatment, although clinical efficacy was superior with bosutinib