Nilotinib as frontline therapy for patients with newly diagnosed Ph+ chronic myeloid leukemia in chronic phase: results from the Japanese subgroup of ENESTnd

Recent results from the phase 3 ENESTnd (Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients) study have demonstrated superiority of nilotinib over imatinib for the treatment of newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia in the chronic phase (CML-CP). Here, we report results from the Japanese subset of patients in ENESTnd, and assess whether results in this subpopulation are consistent with the overall study population. Seventy-nine Japanese patients with CML-CP were randomized to receive nilotinib 300 mg twice daily (BID) (n = 30), nilotinib 400 mg BID (n = 24) or imatinib 400 mg once daily (QD) (n = 25). Major molecular response rates at 12 months, the primary endpoint, were at least twice as high for nilotinib 300 mg BID (57%) and nilotinib 400 mg BID (50%) compared with imatinib 400 mg QD (24%). No patient on nilotinib progressed, while one patient progressed on imatinib. Both drugs were generally well tolerated and discontinuations due to adverse events were comparable among treatment arms. The results in the subpopulation of Japanese patients from ENESTnd closely mirror the results of the overall population, and support the use of nilotinib at 300 mg BID in Japanese patients with newly diagnosed CML-CP.     

Nilotinib is superior to imatinib as first-line therapy of chronic myeloid leukemia: the ENESTnd study

Nilotinib (Tasigna(?)) is a more potent BCR-ABL inhibitor than imatinib and was designed to overcome imatinib's deficiencies. Nilotinib has significant efficacy in patients with chronic myeloid leukemia (CML) in chronic phase, accelerated phase and blastic phase, following imatinib failure. Based on the results of the Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients (ENESTnd) study, the US FDA has granted accelerated approval of nilotinib for the treatment of adult patients with newly diagnosed Philadelphia chromosome-positive CML in chronic phase. Imatinib has changed our perceptions of the therapeutic power of targeted inhibition of a pathologically active kinase. Nilotinib, a designer agent built on the imatinib scaffold, has proven superior to its template agent by every significant surrogate marker we use in monitoring CML. Nilotinib's clinical superiority over imatinib, as demonstrated by the ENESTnd study, has established it as an agent that we believe is a significant further step towards the cure of CML.     

Nilotinib for the treatment of chronic myeloid leukemia

The introduction of targeted therapy has revolutionized the treatment of chronic myeloid leukemia (CML). The pivotal role of the Philadelphia chromosome, resulting from the breakpoint cluster region-Abelson (BCR-ABL) translocation, led to the development of imatinib mesylate, a tyrosine kinase inhibitor with significant activity against the BCR-ABL oncoprotein. Unprecedented clinical activity in CML led to rapid approval and established first-line therapy with imatinib mesylate as the standard of care in most patients. However, the occurrence of imatinib resistance or intolerance has sparked the development of newer drugs with increased activity or specificity. Nilotinib is a second-generation tyrosine kinase inhibitor that has been rationally designed on the basis of imatinib. An overview is given on clinical results in imatinib-resistant or -intolerant patients that led to its current approval as second-line therapy for the chronic and accelerated phases of CML. Future studies will address the role of nilotinib as first-line therapy, in combination strategies and in the context of specific BCR-ABL mutations.     

Long-term pattern of pleural effusion from chronic myeloid leukemia patients in second-line dasatinib therapy

Dasatinib is a potent second-generation tyrosine kinase inhibitor approved for the treatment of chronic myeloid leukemia after imatinib failure. However, some patients treated with dasatinib experience pleural effusions (PEs). The determinants of pleural effusion in long-term dasatinib treatment (median 35 months, range 1–55) were investigated in single-center data of 65 patients enrolled in global phase 2 and phase 3 trials. Of the 65 patients, 35 (54%) developed dasatinib-induced pleural effusion (a median onset time, 20 months; range 0.2–54). The first pleural effusion developed in 15 (43%) patients within 12 months of dasatinib therapy. Disease phase (P = 0.02), dose schedule (P = 0.002) and actual daily mean dose (P = 0.0002) were significantly associated with an increased risk of pleural effusion. Twice-daily administration of dasatinib resulted in significantly more patients developing pleural effusions compared with the once-daily dosing schedule, particularly in advanced disease. In addition, a strong correlation was found between actual daily mean dose and time to onset of pleural effusions in patients treated with a daily mean dose >100 mg/day of dasatinib (P = 0.01). These data emphasize the need for dasatinib dose and schedule optimization and long-term monitoring of dasatinib-treated patients to prevent the negative clinical implications of pleural effusion.     

Second-generation BCR-ABL inhibitors for frontline treatment of chronic myeloid leukemia in chronic phase

Results from several trials in patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP) of dasatinib and nilotinib, two BCR-ABL inhibitors with higher in vitro potency compared with imatinib, have recently been reported. In this review, the rationale for assessing dasatinib and nilotinib in the frontline setting is discussed and data from clinical trials performed to date are summarized, including single-arm studies and randomized trials compared with imatinib. Overall, both dasatinib and nilotinib have shown superior efficacy compared with imatinib during the first year of treatment and longer-term follow-up is needed to confirm that this superiority is maintained over time. Both agents have also shown favorable tolerability profiles, although distinct patterns of adverse events are seen with each agent. Clinicians now have several effective options to treat patients newly diagnosed with CML-CP and available data suggest that dasatinib and nilotinib represent improved therapeutic options compared with imatinib.     

Efficacy and safety of domestic dasatinib as second-line treatment for chronic myeloid leukemia patients in the chronic phase

<正>Objective To investigate the efficiency and safety of domestic tyrosine kinase inhibitor (TKI) dasatinib (Yinishu) as second-line treatment for patients with chronic myeloid leukemia in chronic phase (CML-CP). Methods A retrospective analysis of clinical data of CML-CP     

Treatment modalities in hematology: Imatinib mesylate as therapy for chronic myeloid leukemia

Imatinib mesylate (Glivec^R/Gleevec^R) represents a truly new concept in the treatment of chronic myeloid leukemia (CML) and a breakthrough in the therapy of hematological malignancies in general. It blocks the CML specific tyrosine kinase BCR-ABL. This fusion gene product of the BCR-ABL t(9;22) translocation represents the hallmark of the disease, is constitutively activated and thereby directly involved in the pathological regulation of cell growth. Imatinib is a potent and selective inhibitor in vitro. In phase I and II studies it induced durable hematological responses in more than 90% of all patients with chronic phase CML and in a large proportion of patients even in advanced disease with remarkably few side effects. In a prospective randomised phase III study it was compared in 1,106 patients with newly diagnosed patients with CML to the standard approach for CML, interferon-a combined with low-dose arabinosyl cytosine. At median follow up of 14 months, 84% of patients with imatinib showed a major cytogenetic response (68% complete) compared to 30% (7% complete) in the control arm. Survival rate at 12 months without progression to accelerated phase or blast crisis was 98.5% compared to 93.1% in the control arm (P=0.001). Tolerance to imatinib was significantly better than the interferon based regimen with nausea and fluid retention as main side effects in the imatinib arm. This study illustrates the superiority of imatinib in inducing hematological and cytogenetic remissions, in tolerability and in preventing progression to advanced phase compared to previous therapy. It can be considered as initial treatment for newly diagnosed CML patients. Imatinib sets the standard for future specific tumor therapies to come. *** DIRECT SUPPORT *** A00RC002 00003     

Retrospective multicenter study on the development of peripheral lymphocytosis following second-line dasatinib therapy for chronic myeloid leukemia

The current retrospective study investigated the incidence of lymphocytosis following second-line dasatinib therapy in chronic myeloid leukemia (CML) and analyzed the clinical factors predictive of the development of lymphocytosis, as well as association with treatment outcomes. Fifty CML patients who failed imatinib treatment and received dasatinib were included from nine centers in the Republic of Korea. The cumulative incidence of lymphocytosis was assessed, and cytogenetic and molecular response, treatment failure, loss of response, progression to advanced disease, and survival were evaluated and analyzed according to the development of lymphocytosis. After a median of 17 months of dasatinib therapy, 23 patients (46%) developed lymphocytosis (median onset 4 months). No clinical predictive factor for the development of lymphocytosis was found. The group presenting lymphocytosis showed a higher complete cytogenetic response (CCyR; 78.3 vs. 29.6%, P = 0.001) and major molecular response (MMR; 52.2 vs. 14.8%, P = 0.005), in comparison to the group without presenting lymphocytosis. The development of lymphocytosis after dasatinib was identified as a favorable independent marker for predicting a CCyR (P = 0.002) or MMR (P = 0.003). Further study is necessary to identify which subset of lymphocytes was expanded and to reveal the exact mechanism by which dasatinib induces lymphocyte expansion.     

Nilotinib is effective in patients with chronic myeloid leukemia in chronic phase after imatinib resistance or intolerance: 24-month follow-up results

Nilotinib is a potent selective inhibitor of the BCR-ABL tyrosine kinase approved for use in patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP), and in CML-CP and CML-accelerated phase after imatinib failure. Nilotinib (400 mg twice daily) was approved on the basis of the initial results of this phase 2 open-label study. The primary study endpoint was the proportion of patients achieving major cytogenetic response (CyR). All patients were followed for ≥ 24 months or discontinued early. Of 321 patients, 124 (39%) continue on nilotinib treatment. Overall, 59% of patients achieved major CyR; this was complete CyR (CCyR) in 44%. Of patients achieving CCyR, 56% achieved major molecular response. CyRs were durable, with 84% of patients who achieved CCyR maintaining response at 24 months. The overall survival at 24 months was 87%. Adverse events were mostly mild to moderate, generally transient, and easily managed. This study indicates that nilotinib is effective, with a manageable safety profile, and can provide favorable long-term benefits for patients with CML-CP after imatinib failure.     

Drug treatment is superior to allografting as first-line therapy in chronic myeloid leukemia

Early allogeneic hematopoietic stem cell transplantation (HSCT) has been proposed as primary treatment modality for patients with chronic myeloid leukemia (CML). This concept has been challenged by transplantation mortality and improved drug therapy. In a randomized study, primary HSCT and best available drug treatment (IFN based) were compared in newly diagnosed chronic phase CML patients. Assignment to treatment strategy was by genetic randomization according to availability of a matched related donor. Evaluation followed the intention-to-treat principle. Six hundred and twenty one patients with chronic phase CML were stratified for eligibility for HSCT. Three hundred and fifty four patients (62% male; median age, 40 years; range, 11-59 years) were eligible and randomized. One hundred and thirty five patients (38%) had a matched related donor, of whom 123 (91%) received a transplant within a median of 10 months (range, 2-106 months) from diagnosis. Two hundred and nineteen patients (62%) had no related donor and received best available drug treatment. With an observation time up to 11.2 years (median, 8.9 years), survival was superior for patients with drug treatment (P = .049), superiority being most pronounced in low-risk patients (P = .032). The general recommendation of HSCT as first-line treatment option in chronic phase CML can no longer be maintained. It should be replaced by a trial with modern drug treatment first.     

Management of chronic myeloid leukemia: targets for molecular therapy

Chronic myeloid leukemia (CML) is a hematopoietic disorder characterized by malignant expansion of bone marrow stem cells. Currently, the only unequivocally curative treatment for CML is allogeneic stem cell transplant. Unfortunately, a large proportion of CML patients are ineligible for such treatment and alternative forms of therapy must be employed. Conventional chemotherapy makes use of compounds, such as hydroxyurea, that are cytotoxic for actively dividing cells. Although effective, these agents are not selective for the leukemic clone and this is the cause of undesirable side effects. Moreover, as the disease progresses patients frequently become refractory to chemotherapy. In recent years, knowledge of the molecular pathology of CML has allowed the development of drugs that selectively target the malignant cells: imatinib mesylate is the most prominent example. These agents are selective because they target molecular determinants that are exclusively deregulated in the leukemic cells. In this review we consider some of the novel developments in this field. Particular emphasis is given to chemical agents that target the Bcr-Abl oncoprotein. The latter affords an excellent opportunity for therapy since CML, in contrast to many other human malignancies, is likely caused by the activity of a single oncoprotein. Furthermore, it is believed that Bcr-Abl continues to play a central role throughout the course of the disease.     

Bendamustine compared to fludarabine as second-line treatment in chronic lymphocytic leukemia

Bendamustine demonstrated clinical activity in pre-treated hematological malignancies due to its unique mechanism of action distinct from standard alkylating agents. This study assessed its efficacy in patients with chronic lymphocytic leukemia pre-treated with an alkylator, in comparison to fludarabine. Patients with relapsed chronic lymphocytic leukemia requiring treatment after one previous systemic regimen (usually chlorambucil-based) were randomized to either receive bendamustine 100 mg/m² on days 1 and 2 of a 4-week cycle or standard fludarabine treatment consisting of 25 mg/m² on days 1 to 5 every 4 weeks. The primary objective was to achieve non-inferior progression-free survival (PFS) with bendamustine. Out of a total of 96 patients randomized, 92 were eligible, 49 allocated to bendamustine and 43 to fludarabine. About half of the patients received six or more cycles. Overall response rates were 76 % on bendamustine and 62 % on fludarabine, with clinical complete response rates of 27 and 9 %, respectively. Median PFS was 20.1 and 14.8 months (hazard ratio, 0.87; 90 % confidence interval, 0.60–1.27), median overall survival 43.8 and 41.0 months (hazard ratio, 0.82). Thrombocytopenia and gastrointestinal toxicities were marginally more frequent on bendamustine, albeit CTC grade 3/4 event incidence was similar. These data suggest at least comparable efficacy of bendamustine vs. fludarabine, pointing to an alternative treatment option in relapsing CLL patients after chlorambucil containing initial chemotherapy.     

Vaccines as consolidation therapy for myeloid leukemia

Immunotherapy for myeloid leukemias remains a cornerstone in the management of this highly aggressive group of malignancies. Allogeneic (allo) stem cell transplantation (SCT), which can be curative in acute and chronic myeloid leukemias, exemplifies the success of immunotherapy for cancer management. However, because of its nonspecific immune response against normal tissue, allo-SCT is associated with high rates of morbidity and mortality, secondary to graft-versus-host disease, which can occur in up to 50% of allo-SCT recipients. Targeted immunotherapy using leukemia vaccines has been heavily investigated, as these vaccines elicit specific immune responses against leukemia cells while sparing normal tissue. Peptide and cellular vaccines have been developed against tumor-specific and leukemia-associated self-antigens. Although not yet considered the standard of care, leukemia vaccines continue to show promising results in the management of the myeloid leukemias.     

Outcome of elderly patients after failure to hypomethylating agents given as frontline therapy for acute myeloid leukemia: Single institution experience*

Outcomes of acute myeloid leukemia (AML) in elderly patients unfit for intensive chemotherapy is challenging. Hypomethylating agents (HMAs) can be effective in these patients but responses are usually short‐lived. The majority of patients will either have stable disease or progress through therapy. We hereby describe the outcome of these patients at our institution after they fail HMAs. The data on 56 AML patients at Mayo Clinic, Rochester were reviewed. Patients were considered for our study if they received HMA as frontline therapy for their AML. Out of 56 patients, 15 (27%) patients received azacitidine (AZA) and 41 (73%) received decitabine. Complete remission was found in 10 (18%), with overall response of 28% and median response duration of 10 months. Thirteen (81%) out of 16 responders relapsed. Therefore 53 patients were included in the primary or secondary failure analysis with a median overall survival (OS) of 2 months after the date of failure. Out of 53 patients, 12 (23%) received subsequent treatments. None of the 12 patients who got first salvage therapy achieved remission. Five out of the 12 patients received second salvage therapy, 2 (40%) of which achieved CR. Median OS for patients who received subsequent salvage therapies was better than those who did not receive any subsequent therapy after failing HMA (9.5 vs. 2 months, P = .0009). Outcome for patients who have primary or secondary failure is very poor. Our study provides important historical data for future novel therapies, which are sorely needed for these patients.