Efficacy and Safety of Ponatinib as a Second‑Line Treatment for Chronic‑Phase Chronic Myeloid Leukemia: Retrospective...

The third-generation tyrosine kinase inhibitor (TKI) ponatinib has demonstrated efficacy in patients with chronic phase chronic myeloid leukemia (CML-CP). However, limited data were reported for the use of ponatinib as a second-line treatment in real world evidence. This observational, multicenter, retrospective study included patients aged ≥ 16 years with CML-CP who received ponatinib as second-line therapy between September 2016 and October 2023 at Yokohama City University Medical Center and Fujisawa City Hospital. The median age at the time of data collection was 53 (range, 20-79) years. The median duration of TKI treatment was 15 (range, 1-85) months. The TKIs administered as first-line treatment were as follows: bosutinib in eight patients (50%), dasatinib in six patients (38%), and nilotinib in two patients (13%). Reasons for switching to ponatinib included intolerance (in five patients, 31%) and resistance (in 11 patients, 69%). The median ponatinib exposure was 637 (range, 49-1384) days, with a median follow-up of 1,052 (range, 411-1,732) days. Among the patients, 13 (81%) achieved or maintained major molecular response. Five patients (31%) discontinued ponatinib. Ponatinib demonstrated high efficacy in treating CML-CP resistant or intolerant to second-generation TKIs.