A propensity score matching analysis of dasatinib and nilotinib as a frontline therapy for patients with chronic myeloid leukemia in chronic phase

BACKGROUND: Both dasatinib and nilotinib are approved frontline therapy for chronic myeloid leukemia in chronic phase (CML-CP) based on randomized trials compared with imatinib. However, no head-to-head comparison of dasatinib and nilotinib has been conducted in patients with newly diagnosed CML-CP. METHODS: The authors conducted a propensity score (PS) matched comparison of patients with CML-CP who received frontline therapy with either dasatinib (N = 102) or nilotinib (N = 104) under the respective phase 2 trials conducted in parallel. RESULTS: PS matching resulted in 87 patients from each trial being matched for pretreatment characteristics. The 3-month BCR-ABL1/ABL1 ratio <10% rate was 93% with dasatinib and 94% with nilotinib (P =.25); the rates of major molecular response at 12 months were 77% and 85%, respectively (P =.13); and the rates of molecular response with 4.5-log reduction in the ratio at 36 months were 66% and 64%, respectively (P =.96). All other clinically relevant responses were similar between the 2 treatment cohorts. The 3-year probability of event-free survival was 89% among the patients who received dasatinib and 87% among those who received nilotinib (P =.99), and the corresponding 3-year overall survival probabilities were 99% and 93%, respectively (P =.95). No statistical difference was observed between the dasatinib and nilotinib groups in any of the other survival endpoints. The treatment discontinuation rate also was similar between the 2 cohorts (dasatinib group, 18%; nilotinib group, 19%; P =.82). CONCLUSIONS: In a PS-matched cohort of patients with newly diagnosed CML-CP, dasatinib and nilotinib offer similar response and survival outcomes. Both drugs can be considered reasonable standard-of-care options as first-line therapy for patients with CML-CP. Cancer 2016;122:3336–3343.