Efficacy and safety of second-line ponatinib after failure of a single previous tyrosine kinase inhibitor for chronic myeloid leukemia patients in chronic phase

Adverse effects of dasatinib on glucose-lipid metabolism in patients with chronic myeloid leukaemia in the chronic phase

To explore the differences in glucose-lipid metabolism profiles among the 3 TKIs, we designed a retrospective study to compare the onset of hyperglycaemia, hypertriglyceridemia, hypercholesterolemia and hyper-low density lipoprotein (LDL)-cholesterolemia in the patients with normal baseline glucose-lipid profiles and had no medical record of cardio- or cerebro-vascular diseases and/or metabolic syndrome diseases, and identify variables associated with them. 370 chronic myeloid leukaemia patients receiving dasatinib, nilotinib or imatinib therapy ≥3 months were retrospectively reviewed. During TKI-therapy, the mean fasting glucose, triglyceride, cholesterol, and LDL-cholesterol levels increased significantly in both dasatinib and nilotinib cohorts compared with the imatinib cohort. In multivariate analyses, dasatinib was the factor significantly associated with both poor hyperglycaemia- and hypertriglyceridemia-free survival. In addition, nilotinib was significantly associated with more occurrences of hyperglycaemia and hypercholesterolemia; increasing age was significantly associated with more occurrences of hyperglycaemia and hypertriglyceridemia. We concluded that dasatinib, similar to nilotinib, has the adverse impact on glucose-lipid metabolism compared with imatinib.

Ponatinib in the treatment of chronic myeloid leukemia and philadelphia chromosome positive acute lymphoblastic leukemia

Philadelphia chromosome, reciprocal translocation between chromosome 9 and 22, leading to a constitutively active fusion protein BCR-ABL1 is the common feature among Philadelphia positive acute lymphoblastic leukemia (Ph+ ALL) and chronic myeloid leukemia (CML). The discovery of tyrosine kinase inhibitors (TKIs) has led to significant improvement in the treatment of CML and Ph+ ALL. Ponatinib is a third-generation TKI that is currently approved as per label when no other TKIs are indicated for the treatment of patients with CML and Ph+ ALL after failing treatment with second-generation TKIs or if presence of T315I mutation is discovered. This review summarizes the ponatinib development, approved indications as well as ongoing clinical studies in CML and Ph+ ALL.

Life after ponatinib failure: outcomes of chronic and accelerated phase CML patients who discontinued ponatinib in the salvage setting

Ponatinib is a pan-tyrosine kinase inhibitor (TKI) with efficacy in multirefractory CML patients who have failed other TKIs. Despite excellent response rates, resistance or intolerance may develop. We conducted a retrospective review of the outcome of patients with chronic (CP) and accelerated (AP) phase CML refractory to prior TKI who discontinued ponatinib for resistance or intolerance. Nineteen CP patients, discontinued due to resistance (n = 13), toxicity (n = 5) and to pursue stem cell transplantation (n = 1). At discontinuation, 14 were still in CP, three had progressed to AP and two to blast phase (BP). Three CP patients improved their cytogenetic response (CyR) to complete CyR (CCyR), two after SCT and one on omacetaxine. None of the 12 patients, without a major cytogenetic response at ponatinib discontinuation, including all patients treated with subsequent TKIs, responded to therapy. Seventeen AP patients, stopped ponatinib due to resistance (n = 15) or intolerance (n = 2). At discontinuation, 14 were still in AP and three had progressed to BP. Four patients were treated with SCT and one achieved major molecular response. None of the 12 patients treated with non-SCT approaches responded to subsequent therapy. Median survival for all patients was 16.6 months after ponatinib discontinuation (31, 9 and 13 months for patients in CP, AP and BP, respectively). Median survival was 60 months for patients who discontinued ponatinib for toxicity and 11 months for those who discontinued for resistance. Long-term outcome of patients with ponatinib failure are poor with estimated one-year OS and EFS rates of 54% and 40%, respectively. New treatment options are required for this subset of patients.

Ponatinib as second-line treatment in chronic phase chronic myeloid leukemia patients in real-life practice

Scarce information is available on the use of ponatinib as second-line treatment in chronic phase chronic myeloid leukemia (CP-CML) patients resistant and/or intolerant to prior tyrosine kinase inhibitor (TKI) therapy. We collected data from 29 CML patients, with a median age of 54 years (range 32-72). Eleven patients had received dasatinib, 15 patients received nilotinib, and 3 patients received imatinib as first-line treatment. Forty-five percent of patients started ponatinib for secondary resistance, 38% for primary resistance, 7% for severe intolerance associated to a molecular warning, 7% due to the presence of a T315I mutation, and 3% for severe intolerance. Ponatinib was started at a dose of 45 mg in 60% of patients, 30 mg in 38%, and 15 mg in 2% of patients. Overall, at a median follow-up of 12 months, 85% of treated patients improved the level of response as compared to baseline, with 10 patients achieving a deep molecular response (MR4-4.5). No thrombotic events were recorded. The dose was reduced during treatment in 2 patients due to intolerance and in 8 patients in order to reduce the cardiovascular risk. Ponatinib seems a valid second-line treatment option for chronic phase CML, in particular for patients who failed a front-line second-generation TKI due to BCR-ABL-independent mechanisms of resistance.