Tumor immune escape in acute myeloid leukemia: Class II-associated invariant chain peptide expression as result of deficient antigen presentation

In this overview, we discuss the role of class II-associated invariant chain peptide (CLIP) in acute myeloid leukemia (AML), one of the few tumors expressing HLA class II. The clinical impact, function and regulation of CLIP expression on leukemic cells is addressed, indicating its potential as immunotherapeutic target in AML

Bayesian interim analysis for prospective randomized studies:reanalysis of the acute myeloid leukemia HOVON 132 clinical trial

Randomized controlled trials (RCTs) are the gold standard to establish the benefit-risk ratio of novel drugs. However, the evaluation of mature results often takes many years. We hypothesized that the addition of Bayesian inference methods at interim analysis time points might accelerate and enforce the knowledge that such trials may generate. In order to test that hypothesis, we retrospectively applied a Bayesian approach to the HOVON 132 trial, in which 800 newly diagnosed AML patients aged 18 to 65 years were randomly assigned to a “7 + 3” induction with or without lenalidomide. Five years after the first patient was recruited, the trial was negative for its primary endpoint with no difference in event-free survival (EFS) between experimental and control groups (hazard ratio [HR] 0.99, p = 0.96) in the final conventional analysis. We retrospectively simulated interim analyses after the inclusion of 150, 300, 450, and 600 patients using a Bayesian methodology to detect early lack of efficacy signals. The HR for EFS comparing the lenalidomide arm with the control treatment arm was 1.21 (95% CI 0.81–1.69), 1.05 (95% CI 0.86–1.30), 1.00 (95% CI 0.84–1.19), and 1.02 (95% CI 0.87–1.19) at interim analysis 1, 2, 3 and 4, respectively. Complete remission rates were lower in the lenalidomide arm, and early deaths more frequent. A Bayesian approach identified that the probability of a clinically relevant benefit for EFS (HR &lt; 0.76, as assumed in the statistical analysis plan) was very low at the first interim analysis (1.2%, 0.6%, 0.4%, and 0.1%, respectively). Similar observations were made for low probabilities of any benefit regarding CR. Therefore, Bayesian analysis significantly adds to conventional methods applied for interim analysis and may thereby accelerate the performance and completion of phase III trials.</p

Nilotinib (formerly AMN107), a highly selective BCR-ABL tyrosine kinase inhibitor, is effective in patients with Philadelphia chromosome–positive chronic myelogenous leukemia in chronic phase following imatinib resistance and intolerance

Abstract Nilotinib, an orally bioavailable, selective Bcr-Abl tyrosine kinase inhibitor, is 30-fold more potent than imatinib in pre-clinical models, and overcomes most imatinib resistant BCR-ABL mutations. In this phase 2 open-label study, 400 mg nilotinib was administered orally twice daily to 280 patients with Philadelphia chromosome–positive (Ph+) chronic myeloid leukemia in chronic phase (CML-CP) after imatinib failure or intolerance. Patients had at least 6 months of follow-up and were evaluated for hematologic and cytogenetic responses, as well as for safety and overall survival. At 6 months, the rate of major cytogenetic response (Ph ≤ 35%) was 48%: complete (Ph = 0%) in 31%, and partial (Ph = 1%-35%) in 16%. The estimated survival at 12 months was 95%. Nilotinib was effective in patients harboring BCR-ABL mutations associated with imatinib resistance (except T315I), and also in patients with a resistance mechanism independent of BCR-ABL mutations. Adverse events were mostly mild to moderate, and there was minimal cross-intolerance with imatinib. Grades 3 to 4 neutropenia and thrombocytopenia were observed in 29% of patients; pleural or pericardial effusions were observed in 1% (none were severe). In summary, nilotinib is highly active and safe in patients with CML-CP after imatinib failure or intolerance. This clinical trial is registered at http://clinicaltrials.gov as ID no. NCT00109707

Oral azacitidine prolongs survival of patients with AML in remission independently of measurable residual disease status

Measurable residual disease (MRD) in patients with acute myeloid leukemia (AML) in remission after intensive chemotherapy is predictive of early relapse and poor survival. Postremission maintenance therapy that prolongs MRD negativity or converts MRD+ patients to MRD- status may delay or prevent relapse and improve overall survival (OS). In the phase 3 QUAZAR AML-001 trial, oral azacitidine (oral-AZA; formerly CC-486), a hypomethylating agent, significantly prolonged OS and relapse-free survival (RFS) compared with placebo in patients aged >= 55 years with AML in first remission after intensive chemotherapy who were not candidates for hematopoietic stem cell transplantation. In this trial, MRD (>= 0.1% leukemic cells in bone marrow) was assessed by multiparameter flow cytometry in serial samples collected at baseline and on day 1 of every 3 cycles. As expected, baseline MRD status was significantly associated with both OS and RFS. Multivariate analyses showed oral-AZA significantly improved OS and RFS vs placebo independent of baseline MRD status. Oral-AZA treatment also extended the duration of MRD negativity by 6 months vs placebo and resulted in a higher rate of conversion from MRD+ at baseline to MRD- during treatment: 37% vs 19%, respectively. In the oral-AZA arm, 24% of MRD responders achieved MRD negativity >6 months after treatment initiation. Although presence or absence of MRD was a strong prognostic indicator of OS and RFS, there were added survival benefits with oral-AZA maintenance therapy compared with placebo, independent of patients' MRD status at baseline.Peer reviewe

Measurable residual disease-guided therapy in intermediate-risk acute myeloid leukemia patients is a valuable strategy in reducing allogeneic transplantation without negatively affecting survival.

Not available

Prognostic Value of FLT3-Internal Tandem Duplication Residual Disease in Acute Myeloid Leukemia

PURPOSE The applicability of FLT3-internal tandem duplications (FLT3-ITD) for assessing measurable residual disease (MRD) in acute myeloid leukemia (AML) in complete remission (CR) has been hampered by patient-specific duplications and potential instability of FLT3-ITD during relapse. Here, we comprehensively investigated the impact of next-generation sequencing (NGS)-based FLT3-ITD MRD detection on treatment outcome in a cohort of patients with newly diagnosed AML in relation to established prognostic factors at diagnosis and other MRD measurements, ie, mutant NPM1 and multiparameter flow cytometry. METHODS In 161 patients with de novo FLT3-ITD AML, NGS was performed at diagnosis and in CR after intensive remission induction treatment. FLT3-ITD MRD status was correlated with the cumulative incidence of relapse and overall survival (OS). RESULTS NGS-based FLT3-ITD MRD was present in 47 of 161 (29%) patients with AML. Presence of FLT3-ITD MRD was associated with increased risk of relapse (4-year cumulative incidence of relapse, 75% FLT3-ITD MRD v 33% no FLT3-ITD MRD; P < .001) and inferior OS (4-year OS, 31% FLT3-ITD MRD v 57% no FLT3-ITD MRD; P < .001). In multivariate analysis, detection of FLT3-ITD MRD in CR confers independent prognostic significance for relapse (hazard ratio, 3.55; P < .001) and OS (hazard ratio 2.51; P = .002). Strikingly, FLT3-ITD MRD exceeds the prognostic value of most generally accepted clinical and molecular prognostic factors, including the FLT3-ITD allelic ratio at diagnosis and MRD assessment by NGS-based mutant NPM1 detection or multiparameter flow cytometry. CONCLUSION NGS-based detection of FLT3-ITD MRD in CR identifies patients with AML with profound risk of relapse and death that outcompetes the significance of most established prognostic factors at diagnosis and during therapy, and furnishes support for FLT3-ITD as a clinically relevant biomarker for dynamic disease risk assessment in AML

Impact of age on efficacy and toxicity of nilotinib in patients with chronic myeloid leukemia in chronic phase : ENEST1st subanalysis

Purpose Achievement of deep molecular response with a tyrosine kinase inhibitor in patients with chronic myeloid leukemia (CML) is required to attempt discontinuation of therapy in these patients. The current subanalysis from the Evaluating Nilotinib Efficacy and Safety in Clinical Trials as First-Line Treatment (ENEST1st) study evaluated whether age has an impact on the achievement of deeper molecular responses or safety with frontline nilotinib in patients with CML. Methods ENEST1st is an open-label, multicenter, single-arm, prospective study of nilotinib 300 mg twice daily in patients with newly diagnosed CML in chronic phase. The patients were stratified into the following 4 groups based on age: young (18-39 years), middle age (40-59 years), elderly (60-74 years), and old (>= 75 years). The primary end point was the rate of molecular response 4 ([MR4] BCR-ABL1 Results Of the 1091 patients enrolled, 1089 were considered in the analysis, of whom, 23% (n = 243), 45% (n = 494), 27% (n = 300), and 5% (n = 52) were categorized as young, middle age, elderly, and old, respectively. At 18 months, the rates of MR4 were 33.9% (95% confidence interval [CI], 27.8-40.0%) in the young, 39.6% (95% CI, 35.3-44.0%) in the middle-aged, 40.5% (95% CI, 34.8-46.1%) in the elderly, and 35.4% (95% CI, 21.9-48.9%) in the old patients. Although the incidence of adverse events was slightly different, no new specific safety signals were observed across the 4 age groups. Conclusions This subanalysis of the ENEST1st study showed that age did not have a relevant impact on the deep molecular response rates associated with nilotinib therapy in newly diagnosed patients with CML and eventually on the eligibility of the patients to attempt treatment discontinuation.Peer reviewe