Clinical Features and Treatment Outcomes of 51 Patients with Chronic Myeloid Leukemia Treated with a Tyrosine Kinase Inhibitor at a Single Institution from 2002 to 2014

Serial evaluation of the pharmacokinetics of ponatinib in patients with CML and Ph + ALL

Although tyrosine kinase inhibitors (TKIs) play a crucial role in the treatment of chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL), intolerance and resistance to TKIs have been serious problems. Due to a lack of research, the importance of the pharmacokinetics (PK) of TKIs is currently unclear. We examined the PK of the third-generation TKI ponatinib to monitor side effects and efficacy during treatments for one patient with CML-chronic phase (CP-CML) and two who received allogeneic hematopoietic stem cell transplantation (allo-HSCT), one for CML-blastic crisis (BC-CML) and one for Ph + ALL. The patient with CP-CML was intolerant to multiple TKIs (dasatinib, nilotinib, imatinib, and bosutinib) and thus was switched to ponatinib (15 mg/day). The patients who received allo-HSCT for BC-CML and Ph + ALL received ponatinib (15 mg/day) as maintenance therapy. Notably, serial evaluation of the PK of ponatinib showed that the median trough values (ng/ml) were 17.2 (12.2-34.5), 33.1 (21.2-40.3) and 27.7 (13.6-29.9) in patients 1, 2, and 3, respectively. These values were around the target concentration (23 ng/ml). All patients are maintaining complete remission without side effects. In conclusion, serial evaluation of PK of ponatinib may yield meaningful information about its safety and efficacy.

Evaluation of Molecular Response to Imatinib Mesylate Treatment in Iranian Patients With Chronic Myeloid Leukemia

BACKGROUND

Imatinib mesylate has revolutionized the treatment of patients with chronic myeloid leukaemia (CML); however, some patients fail to respond and have a poor prognosis. Evaluation of molecular response to imatinib is a sensitive method can help physicians make better and quicker therapeutic decisions in the course of this disease. This study aims to evaluate the molecular response to generic imatinib in Iranian patients with CML.

PATIENTS AND METHODS

This prospective study consisted of 255 newly diagnosed patients with CML who received imatinib. Molecular response was analyzed at 3 and 6 months from the start of the treatment and then every 6 months, and long-term outcomes, including overall survival (OS) and progression-free survival (PFS), were evaluated.

RESULTS

At a median follow-up of 34.8 months (range, 3-84 months, (the OS and PFS at 7 years were 94.3% and 92.9%, respectively. Eighty-four-month PFS rates in patients with a BCR-ABLIS ≤ 10% at 3 months and BCR-ABLIS ≤ 1% at 6 months were significantly higher than patients who did not obtain these levels of BCR-ABL transcripts (P = .004 and P < .0001, respectively). The proportion of patients who achieved major molecular response (MMR) was 44.1%, 52.97%, and 60.75% at 12, 18, and 24 months, respectively. At 12, 18, and 84 months, the PFS rates in patients who achieved MMR were significantly higher than in patients who did not achieve MMR (P = .002, P < .0001, and P = .003, respectively).

CONCLUSIONS

The data of this prospective study are highly comparable with that from clinical trials and prospective international studies.