ABSTRACT
BACKGROUND: Nilotinib and dasatinib have shown superior rates of molecular response (MR) compared to imatinib for the treatment of newly diagnosed chronic myeloid leukemia (CML) in chronic phase (CP). This study indirectly compares MR in patients taking nilotinib 300 mg bid with that in those taking dasatinib 100 mg qd by 12 months and through 48 months. METHODS: Patients in ENESTnd were re-weighted to match published baseline characteristics reported for DASISION using a propensity score model. After matching, differences in rates of major MR (MMR, measured as a 3 log reduction on the International Scale [IS]), MR(4.0) (4 log reduction on IS), and MR(4.5) (4.5 log reduction on IS) relative to imatinib were indirectly compared between nilotinib and dasatinib. Hazard ratios (HRs) were used to indirectly compare MR outcomes between nilotinib and dasatinib through 48 months of follow-up, while rate differences were used to compare progression to AP/BC between nilotinib and dasatinib by 48 months. RESULTS: After matching, rates of MR by 12 months were higher with nilotinib vs dasatinib by 11.7% for MMR (p = 0.045), 8.2% for MR(4.0) (p = 0.029), and 8.5% for MR(4.5) (p < 0.001). Higher rates of MMR (HR = 1.44, p = 0.018) and MR(4.0) (HR = 1.58, p = 0.013) achievement were maintained with nilotinib compared to dasatinib through 48 months of follow-up. No statistically significant differences were observed for MR(4.5) through 48 months or progression to AP/BC by 48 months. LIMITATIONS: LIMITATIONS include comparisons based solely on indirect evidence and HRs for MR(4.0) and MR(4.5) from the DASISION trial being extracted from cumulative incidence curves. CONCLUSIONS: This indirect comparison suggests that nilotinib is associated with higher rates of achieving MMR, MR(4.0), and MR(4.5) by 12 months compared to dasatinib for the treatment of newly diagnosed CML-CP. In addition, higher rates of MR achievement with nilotinib were also maintained through 48 months of follow-up.
