Long-term data from a phase 3 study of radotinib versus imatinib in patients with newly diagnosed, chronic myeloid leukaemia in the chronic phase (RERISE).

In the phase 3 study RERISE, patients with newly diagnosed chronic myeloid leukaemia in chronic phase demonstrated significantly faster and higher rates of major molecular response (MMR) with twice-daily radotinib 300 mg (n = 79) or 400 mg (n = 81) than with once-daily imatinib 400 mg (n = 81) after 12 months. With ≥48 months' follow-up, MMR was higher with radotinib 300 mg (86%) or 400 mg (83%) than with imatinib (75%). Among patients with BCR-ABL1 ≤ 10% at three months, MMR and molecular response 4·5 (MR4·5 ) were achieved within 48 months by more radotinib-treated patients (300 mg: 84% and 52%, respectively; 400 mg: 74% and 44%, respectively) than imatinib-treated patients (71% and 44%, respectively). Estimated overall and progression-free survival rates at 48 months were not significantly different between imatinib (94% and 94%, respectively) and radotinib 300 mg (99% and 97%, respectively) or 400 mg (95% and 93%, respectively). The treatment failure rate was significantly higher with imatinib (19%) than with radotinib 300 mg (6%; P = 0·0197) or 400 mg (5%; P = 0·0072). Safety profiles were consistent with previous reports; most adverse events occurred within 12 months. Radotinib continues to demonstrate robust, deep molecular responses, suggesting that treatment-free remission may be attainable.

Longer Hydroxyurea Administration Prior to Imatinib Mesylate is Risk Factor for Unsuccessful Major Molecular Response in Chronic-Phase Chronic Myeloid Leukemia: Possibility of P-Glycoprotein Role.

OBJECTIVE: This study aimed to identify the association between duration of HU administration prior to IM treatment and MMR achievement in chronic-phase CML while evaluating the role of MDA, HIF-1α and P-gp. METHODS: The study was conducted at Dr. Cipto Mangunkusumo National General Hospital and Dharmais Cancer Hospital, Jakarta using retrospective cohort design to analyse the association between the duration of HU before IM and its MMR achievement and cross-sectional design to analyse the association between MDA, HIF-1α and P-gp expressions with MMR achievement. Main subjects were chronic-phase CML patients treated by HU prior to IM for ≥ 12 months and HU only. The subjects were divided into four main groups: (1) chronic-phase CML patients treated with HU ≤ 6 months + IM ≥ 12 months and (2) HU > 6 months + IM ≥ 12 months (3) HU only (≤ 6 months), (4) HU only ( >6 months). Subjects were obtained from January 2015 to May 2016. Data were gathered through history taking, physical examination, medical record evaluation, and blood sample analysis. Bivariate analysis was conducted using chi square, independent T-test, and Mann-Whitney according to the variables. RESULTS: Administration of HU for more than 6 months prior to IM was associated with unsuccessful MMR achievement (RR 1.60; 95%CI 1.29-2.00). MDA level, HIF-1α, P-glycoprotein expression were not associated with MMR achievement but the mean MDA level (0.63±0.31 vs 0.75±0.41 p=0.461) and median P-glycoprotein expressions {16,92 (0,04 - 43,86) vs. 5,15 (0,02-39,64); p=0.311} were found to be higher in patients receiving HU for > 6 months group than in HU ≤ 6 months group consecutively. CONCLUSION: Administration of HU for more than 6 months prior to IM was associated with unsuccessful MMR achievement in chronic-phase CML. The study suggested that P-glycoprotein overexpression as the predictor for unsuccessful MMR achievement.