Four-year minimum follow-up of ongoing patients (pts) with chronic-phase chronic myeloid leukemia (CP-CML) in a phase 1 trial of ponatinib (PON).

7047 Background: PON, an approved oral tyrosine kinase inhibitor (TKI), has potent activity against native BCR-ABL and resistant mutants, including T315I. A phase 1 trial evaluated PON safety and antileukemic activity; this analysis includes 4-year minimum follow-up of ongoing pts, the longest follow-up of PON-treated pts to date. Methods: Pts (N = 81) with resistant/refractory hematologic malignancies received PON (2–60 mg qd) in this ongoing, open-label, dose-escalation trial (NCT00660920; enrollment 2008–2010; data cutoff, 26 Sept 2014). The median follow-up for 43 CP-CML pts was 49.9 (1.7–69.9) mo; minimum follow-up for 22 ongoing CP-CML pts was 50.2 mo. Results: Data are reported for CP-CML pts. Median age was 55 years; time since diagnosis 6.6 years. 60% of pts had received ≥ 3 TKIs; 63% had BCR-ABL mutations (28% T315I). At time of analysis, 51% remained on study. Most common reasons for discontinuation: adverse events (AEs) 26%; progression 9%. By intention-to-treat analysis: major cytogenetic res...