Elias Jabbour

Frequency and clinical significance of BCR-ABL mutations in patients with chronic myeloid leukemia treated with imatinib mesylate

Mutations of the BCR-ABL kinase domain are a common mechanism of resistance to imatinib in chronic myeloid leukemia. We screened for mutations 171 patients failing imatinib therapy. Sixty-six mutations in 23 amino acids were identified in 62 (36%) patients not responding to imatinib. Phosphate-binding loop (P-loop) mutations were the most frequent (n=24; 36%). By multivariate analysis, factors associated with development of mutations were older age (P=0.026) prior interferon therapy (P=0.026), and accelerated phase or blast phase at time of imatinib failure (P=0.001). After a median follow-up of 38 months (range, 4–68 months) from the start of imatinib therapy, seven patients with non-P-loop and two with P-loop mutation died. By multivariate analysis, development of clonal evolution and higher percentage of peripheral blood basophils were associated with worse survival from the time of imatinib failure. Mutation status had no impact on survival. When survival was measured from the time therapy started, non-P-loop mutations together with duration of response and transformation at the time of failure to imatinib were associated with shorter survival. In conclusion, P-loop mutations were not associated with poor outcome, suggesting that the prognosis of patients who fail imatinib is multifactorial.

Inotuzumab ozogamicin, an anti-CD22–calecheamicin conjugate, for refractory and relapsed acute lymphocytic leukaemia: a phase 2 study

BACKGROUND The outlook for patients with refractory and relapsed acute lymphocytic leukaemia (ALL) is poor. CD22 is highly expressed in patients with ALL. Inotuzumab ozogamicin is a CD22 monoclonal antibody conjugated to the toxin calecheamicin. We did a phase 2 study to assess the efficacy of this antibody. METHODS We recruited patients at the MD Anderson Cancer Center, Houston, TX, USA, between June, 2010, and March, 2011. Adults and children with refractory and relapsed ALL were eligible. Ten adults were treated before enrolment of children started. Patients were given 1·8 mg/m(2) inotuzumab ozogamicin intravenously over 1 h every 3-4 weeks (the first three adults and three children received 1·3 mg/m(2) in the first course). The primary endpoint was overall response (complete response or marrow complete response with no recovery of platelet count or incomplete recovery of neutrophil and platelet counts). Analysis was done by intention to treat. This study is registered, number NCT01134575. FINDINGS 49 patients were enrolled and treated. Median age was 36 years (range 6-80). CD22 was expressed in more than 50% of blasts in all patients. The median number of courses was two (range one to five) and the median time between courses was 3 weeks (range 3-6). Nine (18%) patients had complete response, 19 (39%) had marrow complete response, 19 (39%) had resistant disease, and two (4%) died within 4 weeks of starting treatment. The overall response rate was 57% (95% CI 42-71). The most frequent adverse events during course one of treatment were fever (grade 1-2 in 20 patients, grade 3-4 in nine), hypotension (grade 1-2 in 12 patients, grade 3 in one), and liver-related toxic effects (bilirubin: grade 1-2 in 12 patients, grade 3 in two; raised aminotransferase concentration: grade 1-2 in 27 patients, grade 3 in one). INTERPRETATION Inotuzumab ozogamicin shows promise as a treatment for refractory and relapsed ALL. FUNDING Pfizer.

Early response with dasatinib or imatinib in chronic myeloid leukemia: 3-year follow-up from a randomized phase 3 trial (DASISION)

This analysis explores the impact of early cytogenetic and molecular responses on the outcomes of patients with chronic myeloid leukemia in chronic phase (CML-CP) in the phase 3 DASatinib versus Imatinib Study In treatment-Naive CML patients trial with a minimum follow-up of 3 years. Patients with newly diagnosed CML-CP were randomized to receive 100 mg dasatinib (n = 259) or 400 mg imatinib (n = 260) once daily. The retrospective landmark analysis included patients evaluable at the relevant time point (3, 6, or 12 months). Median time to complete cytogenetic response was 3 vs 6 months with dasatinib vs imatinib. At 3 and 6 months, the proportion of patients with BCR-ABL transcript levels ≤10% was higher in the dasatinib arm. Deeper responses at 3, 6, and 12 months were observed in a higher proportion of patients on dasatinib therapy and were associated with better 3-year progression-free survival and overall survival in both arms. First-line dasatinib resulted in faster and deeper responses compared with imatinib. The achievement of an early molecular response was predictive of improved progression-free survival and overall survival, supporting new milestones for optimal response in patients with early CML-CP treated with tyrosine kinase inhibitors. This study was registered at www.clinicaltrials.gov as NCT00481247.

Nilotinib As Front-Line Treatment for Patients With Chronic Myeloid Leukemia in Early Chronic Phase

PURPOSE Although most patients with chronic myeloid leukemia (CML) in chronic phase respond well to front-line therapy with imatinib, some patients do not achieve the desirable end point, and others may eventually lose response or are intolerant. PATIENTS AND METHODS Patients with newly diagnosed CML in chronic phase were treated with nilotinib 400 mg twice daily on an empty stomach as initial therapy. RESULTS Among 51 patients in chronic phase observed for at least 3 months, 50 (98%) achieved a complete cytogenetic remission (CCyR), and 39 (76%) achieved a major molecular response (MMR). Responses occurred rapidly, with 96% of patients achieving CCyR by 3 months and 98% achieving CCyR by 6 months. The projected event-free survival at 24 months is 90%, and all patients are alive after a median follow-up time of 17 months. Grade >or= 3 neutropenia occurred in 12% of patients, and thrombocytopenia in occurred 11%. Nonhematologic toxicity was usually grade 1 to 2 and manageable. The actual median dose at 12 months was 800 mg (range, 200 to 800 mg). CONCLUSION Nilotinib is an effective option for the initial management of CML in early chronic phase, producing high rates of CCyR and MMR, with most patients reaching these responses early during their therapy.

Results of Dasatinib Therapy in Patients With Early Chronic-Phase Chronic Myeloid Leukemia

PURPOSE Dasatinib is effective therapy for chronic myeloid leukemia (CML) after imatinib failure. In this study, we investigate the efficacy of dasatinib as initial therapy for patients with CML in early chronic phase. PATIENTS AND METHODS Patients with newly diagnosed CML in early chronic phase were randomly assigned to receive dasatinib 100 mg once daily or 50 mg twice daily as initial therapy. RESULTS Among 50 patients observed for at least 3 months, 49 patients (98%) achieved a complete cytogenetic response (CCyR), and 41 patients (82%) achieved a major molecular response (MMR). Responses occurred rapidly, with 94% of patients achieving CCyR by 6 months. There was no difference in response rate by treatment arm. The projected event-free survival rate at 24 months is 88%, and all patients are alive after a median follow-up time of 24 months. Grade >or= 3 neutropenia and thrombocytopenia occurred in 21% and 10% of patients, respectively. Nonhematologic toxicity was usually grade 1 to 2. There was no significant difference in toxicity between the two arms, and the actual median dose at 12 months was 100 mg (range, 20 to 100 mg). CONCLUSION Dasatinib is an effective agent for the initial management of CML in early chronic phase, producing high rates of CCyR and MMR.

Chronic myeloid leukemia: 2012 update on diagnosis, monitoring, and management.

Chronic Myeloid Leukemia (CML) is a myeloproliferative neoplasm with an incidence of one–two cases per 100,000 adults and accounts for ∼15% of newly diagnosed cases of leukemia in adults.

Intensive chemotherapy does not benefit most older patients (age 70 years or older) with acute myeloid leukemia

Patients ≥ 70 years of age with acute myeloid leukemia (AML) have a poor prognosis. Recent studies suggested that intensive AML-type therapy is tolerated and may benefit most. We analyzed 446 patients ≥ 70 years of age with AML (≥ 20% blasts) treated with cytarabine-based intensive chemotherapy between 1990 and 2008 to identify risk groups for high induction (8-week) mortality. Excluding patients with favorable karyotypes, the overall complete response rate was 45%, 4-week mortality was 26%, and 8-week mortality was 36%. The median survival was 4.6 months, and the 1-year survival rate was 28%. Survival was similar among patients treated before 2000 and since 2000. A multivariate analysis of prognostic factors for 8-week mortality identified the following to be independently adverse: age ≥ 80 years, complex karyotypes, (≥ 3 abnormalities), poor performance (2-4 Eastern Cooperative Oncology Group), and elevated creatinine > 1.3 mg/dL. Patients with none (28%), 1 (40%), 2 (23%), or ≥ 3 factors (9%) had estimated 8-week mortality rates of 16%, 31%, 55%, and 71% respectively. The 8-week mortality model also predicted for differences in complete response and survival rates. In summary, the prognosis of most patients (72%) ≥ 70 years of age with AML is poor with intensive chemotherapy (8-week mortality ≥ 30%; median survival < 6 months).

Improved survival in chronic myeloid leukemia since the introduction of imatinib therapy: a single-institution historical experience

A total of 1569 patients with chronic myeloid leukemia (CML) referred to our institution within 1 month of diagnosis since 1965 were reviewed: 1148 chronic phase (CP), 175 accelerated phase (AP), and 246 blastic phase (BP). The median survival was 8.9 years in CP, 4.8 years in AP, and 6 months in BP. In CP, the 8-year survival was ≤ 15% before 1983, 42%-65% from 1983-2000, and 87% since 2001. Survival was worse in older patients (P = .004), but this was less significant since 2001 (P = .07). Survival by Sokal risk was significantly different before 2001 (P < .001), but not since 2001 (P = .4). In AP, survival improved over time (P < .001); the 8-year survival in patients treated since 2001 was 75%. Survival by age was not different in years < 2001 (P = .09), but was better since 2001 in patients ≤ 70 years of age (P = .004). In BP, the median survival improved over time (P < .001), although it has been only 7 months since 2001. In summary, survival in CML has significantly improved since 2001, particularly so in CP-AML and AP-CML. Imatinib therapy minimized the impact of known prognostic factors and Sokal risk in CP-CML and accentuated the impact of age in AP- and BP-CML.

Low-dose azacitidine after allogeneic stem cell transplantation for acute leukemia

The authors hypothesized that low doses of the hypomethylating agent 5‐azacitidine may maximize the graft‐versus‐leukemia effect and may be tolerated well after allogeneic transplantation (HSCT).

Long-term outcomes of 107 patients with myelofibrosis receiving JAK1/JAK2 inhibitor ruxolitinib: survival advantage in comparison to matched historical controls.

Ruxolitinib is JAK1/JAK2 inhibitor with established clinical benefit in myelofibrosis (MF). We analyzed long-term outcomes of 107 patients with intermediate-2 or high-risk MF receiving ruxolitinib at MD Anderson Cancer Center (MDACC) on phase 1/2 trial. After a median of 32 months of follow-up, 58 patients (54%) were still receiving ruxolitinib, with overall survival (OS) of 69%. The splenomegaly and symptom reductions achieved with ruxolitinib were sustained with long-term therapy. Therapy was well tolerated; discontinuation rates at 1, 2, and 3 years were 24%, 36%, and 46%, respectively. OS of 107 MDACC patients was significantly better (P = .005) than that of 310 matched (based on trial enrollment criteria) historical control patients, primarily because of highly significant difference in OS in the high-risk subgroup (P = .006). Furthermore, among MDACC patients, those with high-risk MF experienced the same OS as those with intermediate-2 risk. Patients with ≥ 50% reduction in splenomegaly had significantly prolonged survival versus those with < 25% reduction (P < .0001). Comparison of discontinuation rates and reasons for stopping the therapy to those reported for other 51 patients in the phase 1/2 trial, and 155 ruxolitinib-treated patients in phase 3 COMFORT-I study, suggest that continued therapy with ruxolitinib at optimal doses contributes to the benefits seen, including OS benefit.