Oral Azacitidine Maintenance Therapy for Acute Myeloid Leukemia in First Remission.

BACKGROUND: Although induction chemotherapy results in remission in many older patients with acute myeloid leukemia (AML), relapse is common and overall survival is poor. METHODS: We conducted a phase 3, randomized, double-blind, placebo-controlled trial of the oral formulation of azacitidine (CC-486, a hypomethylating agent that is not bioequivalent to injectable azacitidine), as maintenance therapy in patients with AML who were in first remission after intensive chemotherapy. Patients who were 55 years of age or older, were in complete remission with or without complete blood count recovery, and were not candidates for hematopoietic stem-cell transplantation were randomly assigned to receive CC-486 (300 mg) or placebo once daily for 14 days per 28-day cycle. The primary end point was overall survival. Secondary end points included relapse-free survival and health-related quality of life. RESULTS: A total of 472 patients underwent randomization; 238 were assigned to the CC-486 group and 234 were assigned to the placebo group. The median age was 68 years (range, 55 to 86). Median overall survival from the time of randomization was significantly longer with CC-486 than with placebo (24.7 months and 14.8 months, respectively; P<0.001). Median relapse-free survival was also significantly longer with CC-486 than with placebo (10.2 months and 4.8 months, respectively; P<0.001). Benefits of CC-486 with respect to overall and relapse-free survival were shown in most subgroups defined according to baseline characteristics. The most common adverse events in both groups were grade 1 or 2 gastrointestinal events. Common grade 3 or 4 adverse events were neutropenia (in 41% of patients in the CC-486 group and 24% of patients in the placebo group) and thrombocytopenia (in 22% and 21%, respectively). Overall health-related quality of life was preserved during CC-486 treatment. CONCLUSIONS: CC-486 maintenance therapy was associated with significantly longer overall and relapse-free survival than placebo among older patients with AML who were in remission after chemotherapy. Side effects were mainly gastrointestinal symptoms and neutropenia. Quality-of-life measures were maintained throughout treatment. (Supported by Celgene; QUAZAR AML-001 ClinicalTrials.gov number, NCT01757535.).

Validation of National Early Warning Score and Quick Sequential (sepsis-related) Organ Failure Assessment in acute myeloid leukaemia patients treated with intensive chemotherapy.

OBJECTIVES: Chemotherapy-induced neutropenia in acute myeloid leukaemia (AML) is a risk factor for life-threatening infections. Early diagnosis and prompt interventions are associated with better outcomes, but the prediction of infection severity remains an open question. Recently, National Early Warning Score (NEWS) and quick sequential organ failure assessment (qSOFA) scores were proposed as warning clinical instruments predicting in-hospital mortality, but their role in the haematological context is still unknown. METHODS: We retrospectively assess the predictive role of NEWS and qSOFA in a large and homogeneous cohort of adult AML patients treated with intensive chemotherapy. In a total of 1048 neutropenic episodes recorded in 334 consecutive patients, the scores were applied to predict outcomes on the same day of fever onset, and after 24 and 48 h from score calculation. RESULTS: Both NEWS and qSOFA significantly predicted death, with more accuracy on the same day (NEWS AUROC 0.984 and qSOFA AUROC 0.969) and after 24 h (NEWS AUROC 0.928 and qSOFA AUROC 0.887), while remained moderately accurate after 48 h. Furthermore, also ICU admission was accurately predicted at fever onset and after 24 h. CONCLUSIONS: Both scores were useful tools in the management of post chemotherapy neutropenic febrile AML patients.

Frequency and risk factors for thrombosis in acute myeloid leukemia and high-risk myelodysplastic syndromes treated with intensive chemotherapy: a two centers observational study.

The frequency of thrombosis in AML has been evaluated only in a few studies and no validated predictive model is currently available. Recently, DIC score was shown to identify patients at higher thrombotic risk. We aimed to evaluate the frequency of thromboembolism in AML patients treated with intensive chemotherapy and to assess the ability of genetic and clinical factors to predict the thrombotic risk. We performed a retrospective observational study including 222 newly diagnosed adult AML (210) and high-risk MDS (12), treated with intensive chemotherapy between January 2013 and February 2020. With a median follow-up of 44 months, we observed 50 thrombotic events (90% were venous, VTE). The prevalence of thrombosis was 22.1% and the 6-months cumulative incidence of thrombosis was 10%. The median time to thrombosis was 84 days and 52% of the events occurred within 100 days from AML diagnosis. Khorana and DIC score failed to stratify patients according to their thrombotic risk. Only history of a thrombotic event (p = 0.043), particularly VTE (p = 0.0053), platelet count above 100 × 109/L at diagnosis (p = 0.036) and active smoking (p = 0.025) significantly and independently increased the risk of thrombosis, the latter particularly of arterial events. AML genetic profile did not affect thrombosis occurrence. Results were confirmed considering only thromboses occurring within day 100 from diagnosis. DIC score at diagnosis, but not thrombosis, was independently associated with reduced survival (p = 0.004). Previous VTE, platelet count above 100 × 109/L and active smoking were the only factors associate with increased thrombotic risk in AML patients treated intensively, but further studies are needed to validate these results.

Gilteritinib in Isolated Breast Relapse of FLT3 Positive Acute Myeloid Leukemia: A Case Report and Review of Literature.

Extramedullary relapse of acute myeloid leukemia (AML) is not a rare event, and the FMS-like tyrosine kinase 3 (FLT3) mutation is a well-known risk factor. Gilteritinib is approved for relapsed/refractory FLT3+ AML, but its efficacy in extramedullary relapse is still undefined. Here, we present the case of a 69-year-old woman with therapy-related nucleophosmin-1 and FLT3-internal tandem duplication (FLT3-ITD) positive AML treated with induction and consolidation with CPX-351 (liposomal daunorubicin plus cytarabine) followed by off-label azacitidine maintenance who obtained a complete remission (CR) with persistent measurable residual disease. After 19 months of CR, she experienced an isolated breast relapse of FLT3-ITD+ AML. She was started on single-agent gilteritinib, resulting in a rapid and persistent complete regression of the breast nodule. Targeted therapy with gilteritinib for relapsed/refractory FLT3-ITD+ AML can be effective in isolated extramedullary relapse.

Sole Upfront Therapy with Beclomethasone and Budesonide for Upper Gastrointestinal Acute Graft-versus-Host Disease.

Systemic glucocorticoids remain the standard treatment for gastrointestinal (GI) acute graft-versus-host disease (aGVHD) despite their toxicity and incomplete efficacy. Controlled trials have tested poorly absorbable steroids as adjuncts with systemic glucocorticoids, but only small case series have reported treatment with poorly absorbed beclomethasone dipropionate (BDP) and budesonide (BUD) alone. Our team has adopted the practice of administering BDP or BDP+BUD without systemic glucocorticoids as first-line therapy for isolated upper GI (UGI) aGVHD. We report results in 76 patients treated with BDP alone and in 81 patients treated with BDP+BUD, with allocation by physician choice. Almost all patients received peripheral blood stem cells (92%) from a fully HLA-matched related or unrelated donor (80%) after myeloablative conditioning (76%) for acute leukemia (49%), myelodysplastic syndrome (17%), non-Hodgkin lymphoma (14%), or another hematopoietic disorders (20%). After 28 days of treatment with BDP, 46% of the patients had a complete response (CR) and 10% had a partial response (PR); after 200 days, 61 (80%) patients were alive, 34% maintained a CR, and 3% maintained a PR, whereas 53% required additional immunosuppression (IS). After 28 days of treatment with BDP+BUD, 67% had a CR and 10% a PR; after 200 days, 74 (91%) patients were alive, 46% maintained a CR, and 2% maintained a PR, whereas 43% required additional IS. Among the entire cohort of 157 patients, 66 (42%) were treated successfully without systemic glucocorticoids. This study reports the efficacy of poorly absorbable steroids alone for patients with isolated UGI aGVHD. Prospective trials should test for the potential advantages of BDP and BUD use over systemic glucocorticoids.

The use of erythropoiesis-stimulating agents is safe and effective in the management of anaemia in myelofibrosis patients treated with ruxolitinib.

Erythropoiesis-stimulating agents (ESAs) were combined with ruxolitinib in 59 anaemic myelofibrosis patients (93% with Dynamic International Prognostic Scoring System [DIPSS] intermediate-2/high risk; 52·5% transfusion-dependent). Anaemia response (AR) rate was 54% and 76% of patients responded at 5 years. A further 15% displayed minor improvement in anaemia and 78% of patients reduced spleen size. Endogenous erythropoietin levels <125 u/l correlated with a higher AR rate (63% vs. 20%, P = 0·008). No thrombotic events or other toxicities occurred. Overall survival was 62% at 4 years, influenced by DIPSS and transfusion dependency. ESAs seem effective in improving anaemia in ruxruxolitinib-treated myelofibrosis patients.

Survival improvement of poor-prognosis AML/MDS patients by maintenance treatment with low-dose chemotherapy and differentiating agents.

We evaluated a maintenance, post-remission treatment with low-dose chemotherapy plus differentiating agents on poor-prognosis acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) patients ineligible to allografting. Patients had either age over 60 and/or secondary AML, therapy-related AML, previous relapse, high-risk MDS. Forty-five patients received the maintenance therapy based on two alternated schedules: (a) 6-thioguanine + 13-cis retinoic acid + dihydroxylated vitamin D3 and (b) low-dose cytarabine + 6-mercaptopurine + all-trans retinoic acid + dihydroxylated vitamin D3. We compared their outcome, at a median follow-up of 52 months, to that of a matched population of 49 patients who stopped treatments after consolidation. Maintenance group had a lower relapse incidence (70.3 vs. 86.4 % at 5 years p = 0.007) and a longer disease-free survival (median 21.2 vs. 8.7 months, p = 0.017). The relapse reduction improved overall survival: median 40.4 months (35.9 % at 5 years) for maintenance group vs. 15.8 (14.2 % at 5 years) for controls (p = 0.005). At multivariate Cox analysis, both cytogenetic and maintenance therapies resulted independent outcome predictors for overall survival. Maintenance treatment also reduced minimal residual disease (detected by WT1 and CBFß-MYH11) in five of eight evaluable patients. The present results suggest that our strategy of maintenance therapy might improve the outcome of poor-risk AML/MDS patients.

Transfusion independence after lenalidomide discontinuation in patients with del(5q) myelodysplastic neoplasm: a HARMONY Alliance study.

Lenalidomide (LEN) can induce red blood cell-transfusion independence (RBC-TI) in 60-70% of del(5q) myelodysplastic neoplasm (MDS) patients. Current recommendation is to continue LEN in responding patients until failure or progression, with likelihood of toxicity and a high cost for healthcare systems. This HARMONY Alliance study investigated the outcome of MDS del(5q) patients who discontinued LEN while RBC-transfusion independent. We enrolled 118 patients with IPSS-R low-intermediate risk. Seventy patients (59%) discontinued LEN for intolerance, 38 (32%) per their physician decision, nine (8%) per their own decision and one (1%) for unknown reasons. After a median follow-up of 49 months from discontinuation, 50/118 patients lost RBC-TI and 22/30 who underwent cytogenetic re-evaluation lost complete cytogenetic response. The median RBC-TI duration was 56 months. In multivariate analysis, RBC-TI duration after LEN discontinuation correlated with low transfusion burden before LEN therapy, treatment ≥ 12 LEN cycles, younger age and higher Hb level at LEN withdrawal. Forty-eight patients were re-treated with LEN for loss of response and 28 achieved again RBC-TI. These data show that stopping LEN therapy in MDS del(5q) patients who reached RBC-TI allows prolonged maintenance of TI in a large subset of patients.

Epidemiology of bloodstream infections in patients with acute myeloid leukemia undergoing levofloxacin prophylaxis.

BACKGROUND: Infections are a common cause of morbidity and mortality in patients with acute myeloid leukemia (AML). The evidence for efficacy of antibiotic prophylaxis in reducing the mortality rates and the incidence of bacterial infections was also reported by a systematic review published by Cochrane in 2012. The objective of our study was to report the incidence and the etiology of bloodstream infections in patients with AML undergoing levofloxacin prophylaxis during neutropenic episodes. METHODS: This was a retrospective study of patients with diagnosis of AML during 2001-2007. RESULTS: A total of 81 patients were included in the study. Two hundred and ninetyone neutropenic episodes were studied, of which 181 were febrile. Bacteria isolated from blood cultures were mostly Gram-positives during the induction (80%) and Gram-negatives during the consolidation (72.4%) phases of chemotherapy. Resistance to ciprofloxacin was found in 78.9% of isolated E. coli and it was higher during consolidation and higher than the hospital rate. The production of extended spectrum betalactamases (ESBL) in E. coli strains was reported in 12.1%, below the reported hospital rate during the study period. CONCLUSIONS: Regular microbiology surveillance is needed to better understand the impact of levofloxacin prophylaxis in neutropenic patients. Our study shows that Gram-positive bacteria are predominant during the induction phase of chemotherapy and Gram-negatives during the consolidation. The rate of fluoroquinolone resistance in the latter setting, even higher than the hospital rate, may suggest to reconsider levofloxacin prophylaxis.

Levofloxacin Prophylaxis Versus no Prophylaxis in Acute Myeloid Leukemia During Post-Induction Aplasia: a Single Center Study.

Background: Acute myeloid leukemia (AML) patients are at high risk of infections during post-induction neutropenia. Recently, the role of antibacterial prophylaxis has been reconsidered due to concerns about the emergence of multi-resistant pathogens. The aim of the present study was to evaluate the impact of avoiding prophylaxis on the rate of induction death (primary endpoint), neutropenic fevers, bloodstream infections (BSIs), resistant pathogens BSIs and septic shocks (secondary endpoints). Methods: We performed a retrospective single-center study including 373 AML patients treated with intensive induction chemotherapy, divided into two groups according to levofloxacin prophylaxis given (group A, gA) or not (group B, gB). Results: Neutropenic fever was observed in 91% of patients in gA and 97% in gB (OR 0.35, IC95% 0.08 - 1.52, p=0162). The rate of BSIs was 27% in gA compared to 34% in gB (OR 0.69, 0.38 - 1.25, p=0.222). The induction death rate was 5% in gA and 3% in gB (OR 1.50, 0.34 - 6.70, p=0.284). Fluoroquinolones (FQ) resistant pathogens were responsible for 59% of total BSIs in gA and 22% in gB (OR 5.07, 1.87 - 13.73, p=0.001); gram-negative BSIs due to multi-drug resistant organisms were 31% in gA and 36% in gB (OR 0.75, 0.15 - 3.70, p=0.727). Conclusions: Despite its limitations (retrospective nature, single-center, different cohort size), the present study showed that avoiding levofloxacin prophylaxis was not associated with an increased risk of induction death. The cumulative incidence of neutropenic fever was higher in non-prophylaxis group, while no difference was observed for BSIs. In the prophylaxis group we observed a higher incidence of FQ-resistant organisms.

Modern Risk Stratification of Acute Myeloid Leukemia in 2023: Integrating Established and Emerging Prognostic Factors.

An accurate estimation of AML prognosis is complex since it depends on patient-related factors, AML manifestations at diagnosis, and disease genetics. Furthermore, the depth of response, evaluated using the level of MRD, has been established as a strong prognostic factor in several AML subgroups. In recent years, this rapidly evolving field has made the prognostic evaluation of AML more challenging. Traditional prognostic factors, established in cohorts of patients treated with standard intensive chemotherapy, are becoming less accurate as new effective therapies are emerging. The widespread availability of next-generation sequencing platforms has improved our knowledge of AML biology and, consequently, the recent ELN 2022 recommendations significantly expanded the role of new gene mutations. However, the impact of rare co-mutational patterns remains to be fully disclosed, and large international consortia such as the HARMONY project will hopefully be instrumental to this aim. Moreover, accumulating evidence suggests that clonal architecture plays a significant prognostic role. The integration of clinical, cytogenetic, and molecular factors is essential, but hierarchical methods are reaching their limit. Thus, innovative approaches are being extensively explored, including those based on "knowledge banks". Indeed, more robust prognostic estimations can be obtained by matching each patient's genomic and clinical data with the ones derived from very large cohorts, but further improvements are needed.

Health-related Quality of Life Profile of Newly Diagnosed Patients With Myelodysplastic Syndromes by Age, Sex, and Risk Group: A Real-world Study by the GIMEMA.

Health-related quality of life (HRQoL) is an important goal of therapy for patients with myelodysplastic syndromes (MDS); however, little is known about HRQoL of these patients at clinical presentation. We report HRQoL profile of newly diagnosed patients with MDS across both the the International Prognostic Scoring System (IPSS) and IPSS-Revised (IPSS-R) classifications, stratified by sex and age group categories, aiming to also establish European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core30 (EORTC QLQ-C30) reference values for these patients. Analysis was based on 927 patients with a median age of 73.3 years (interquartile range, 66.0-79.2), of whom 506 and 421 with lower- and higher-risk disease respectively, according to the IPSS classification. HRQoL was assessed with the EORTC QLQ-C30 and substantial differences by age groups and sex, between and within lower- and higher-risk disease categories were observed. For example, within higher-risk disease patients, the youngest group (ie, 30-59 years) tended to report clinically meaningful worse outcomes across various functional and symptom domains compared with older age groups. We also developed 2 regression models allowing for the prediction of EORTC QLQ-C30 reference scores for patients classified according to either the IPSS or the IPSS-R. Investigation of prevalence rates for clinically important problems and symptoms at diagnosis revealed a substantial burden of the disease with >50% of patients reporting clinically important problems with physical functioning and dyspnea in both lower- and higher-risk disease. Our findings may help to enhance the interpretation of HRQoL outcomes in future MDS studies and to better contextualize HRQoL data from routine practice settings.

RD-CODOX-M/IVAC with rituximab and intrathecal liposomal cytarabine in adult Burkitt lymphoma and 'unclassifiable' highly aggressive B-cell lymphoma.

Specific trials on adult Burkitt lymphoma (BL) and 'unclassifiable' lymphomas with features intermediate between BL and diffuse large B-cell lymphoma (BL/DLBCL) are advocated which include substantial numbers of older patients, to improve treatment feasibility, while countering risks of systemic and central nervous system (CNS) recurrences. We prospectively evaluated a modified CODOX-M/IVAC (CODOX-M: cyclophosphamide, vincristine, doxorubicin, high-dose methotrexate; IVAC: ifosfamide, etoposide and high-dose cytarabine) regimen by the addition of rituximab (R) and liposome-encapsulated cytarabine (D) to increase antitumour activity and halve the number of intrathecal treatments. Thirty adults (40% >60years) with BL (n=15) and BL/DLBCL (n=15) were accrued. Primary endpoints were progression-free survival (PFS), CNS recurrence, and liposomal cytarabine-associated toxicity. Eighty percent of patients received the whole treatment programme, the remaining cases received at least three full courses. Application of the RD-CODOX-M/IVAC regimen resulted in remarkable 4-year PFS (78%) and complete remission (CR) rates (93%). However, PFS was significantly lower in patients older than 60years as compared to younger ones (49%vs 93%, P=0·03; median, 36months), despite high actual dose-intensity, CR rate and tolerability. Reduced-intensity intratechal prophylaxis through liposomal cytarabine was effective because the CNS failure rate was low (3·4%) and without severe neurological toxicities. The RD-CODOX-M/IVAC strategy is feasible and highly effective, but improving outcomes in elderly patients remains a priority.

Evolving Therapeutic Approaches for Older Patients with Acute Myeloid Leukemia in 2021.

Acute myeloid leukemia (AML) in older patients is characterized by unfavorable prognosis due to adverse disease features and a high rate of treatment-related complications. Classical therapeutic options range from intensive chemotherapy in fit patients, potentially followed by allogeneic hematopoietic cell transplantation (allo-HCT), to hypomethylating agents or palliative care alone for unfit/frail ones. In the era of precision medicine, the treatment paradigm of AML is rapidly changing. On the one hand, a plethora of new targeted drugs with good tolerability profiles are becoming available, offering the possibility to achieve a prolonged remission to many patients not otherwise eligible for more intensive therapies. On the other hand, better tools to assess patients' fitness and improvements in the selection and management of those undergoing allo-HCT will hopefully reduce treatment-related mortality and complications. Importantly, a detailed genetic characterization of AML has become of paramount importance to choose the best therapeutic option in both intensively treated and unfit patients. Finally, improving supportive care and quality of life is of major importance in this age group, especially for the minority of patients that are still candidates for palliative care because of very poor clinical conditions or unwillingness to receive active treatments. In the present review, we discuss the evolving approaches in the treatment of older AML patients, which is becoming increasingly challenging following the advent of new effective drugs for a very heterogeneous and complex population.

The IPSS-R more accurately captures fatigue severity of newly diagnosed patients with myelodysplastic syndromes compared with the IPSS index.

We aimed to compare fatigue of newly diagnosed patients with myelodysplastic syndromes (MDS) with that of the general population (GP). We also investigated the ability of the IPSS and IPSS-R to capture severity of patient-reported fatigue at diagnostic workup. A sample of 927 newly diagnosed patients with MDS was consecutively enrolled in a large international observational study and all patients completed the FACIT-Fatigue questionnaire at baseline. Fatigue was compared with that of the GP (N = 1075) and a 3-point difference in mean scores was considered as clinically meaningful. Fatigue of MDS patients was on average 4.6 points below the mean of the GP (95% CI, -5.9 to -3.2, p < 0.001), reflecting clinically meaningful worse fatigue. Unlike the IPSS, the IPSS-R identified clearly distinct subgroups with regard to burden of fatigue. Mean scores differences compared with GP ranged from nonclinically relevant for very low risk (Δ = -1.8, 95% CI, -4.0 to 0.5, p = 0.119) to large clinically meaningful differences for very high-risk IPSS-R patients (Δ = -8.2, 95% CI, -10.3 to -6.2, p < 0.001). At diagnostic workup, fatigue of MDS is clinically meaningful worse than that reported by the GP. Compared with the IPSS classification, the IPSS-R provides a better stratification of patients with regard to fatigue severity.

Hematopoietic cell transplantation comorbidity index and risk of developing invasive fungal infections after allografting.

We evaluated the potential correlation of the hematopoietic cell transplantation comorbidity index (HCT-CI) with the risk of developing post-transplant invasive fungal infections (IFIs). Between January 2009 and March 2015, 312 consecutive patients who received a first allograft entered the study. Low/intermediate HCT-CI risk score (0-2) was observed in 172/312 (55%), whereas high HCT-CI score (≥3) was seen in 140/312 (45%). Overall, 51/312 (16%) patients experienced IFI, defined as possible in 19 (6%), probable in 27 (9%), and proven in 5 (2%). Cumulative incidence of probable-proven IFI at 1 year was 8.5% with a significant higher incidence in patients with high HCT-CI (12%) vs. those with low-intermediate HCT-CI (5%; p = 0.006). There was a strong trend for a higher incidence of baseline severe pulmonary comorbidity in patients who developed probable-proven IFI (p = 0.051). One-year cumulative incidence of non-relapse mortality was higher in patients with IFI vs. those without, 49 and 16% (p < 0.001). By multivariate analysis, disease status at transplant and high HCT-CI, when combined with acute GVHD, were independently associated with the risk of post-transplant IFI. This study shows that a high HCT-CI predicts the risk of developing IFI and may indicate the need of mold-active antifungal prophylaxis in high-risk patients.

Post-remissional and pre-transplant role of minimal residual disease detected by WT1 in acute myeloid leukemia: A retrospective cohort study.

In acute myeloid leukemia (AML), the detection of minimal residual disease (MRD) is still under investigation. The aim of the present retrospective study was to assess the role of Wilms tumor gene 1 (WT1) overexpression in a large monocentric cohort of AML patients. Among 255 enrolled patients, MRD was investigated in those in complete remission (CR) with an available WT1 at baseline (>250 copies) and at two further time-points: after induction (n=117) and prior allogeneic hematopoietic cell transplantation (allo-HCT), n=65. Baseline BM WT1 overexpression was not associated with response to induction (p=0.244). Median overall survival (OS) and disease-free survival (DFS) were significantly shorter in patients with >350 WT1 copies after induction compared to those with ≤350 (HR for mortality 2.13; 95% CI 1.14-3.97, p=0.018 and HR for relapse 2.81; 95% CI 1.14-6.93, p=0.025). Patients with WT1>150 copies pre allo-HCT had a significantly higher 2-year cumulative incidence of relapse (CIR) compared to those with WT1≤150 (HR 4.61; 95% CI 1.72-12.31, p=0.002). The prognostic role of WT1 overexpression resulted independent from other well-established risk factors. According to these results, WT1 overexpression might represent an additional MRD tool for risk stratification in patients classified nowadays in CR.

Improved Outcomes With Retinoic Acid and Arsenic Trioxide Compared With Retinoic Acid and Chemotherapy in Non-High-Risk Acute Promyelocytic Leukemia: Final Results of the Randomized Italian-German APL0406 Trial.

Purpose The initial results of the APL0406 trial showed that the combination of all- trans-retinoic acid (ATRA) and arsenic trioxide (ATO) is at least not inferior to standard ATRA and chemotherapy (CHT) in first-line therapy of low- or intermediate-risk acute promyelocytic leukemia (APL). We herein report the final analysis on the complete series of patients enrolled onto this trial. Patients and Methods The APL0406 study was a prospective, randomized, multicenter, open-label, phase III noninferiority trial. Eligible patients were adults between 18 and 71 years of age with newly diagnosed, low- or intermediate-risk APL (WBC at diagnosis ≤ 10 × 109/L). Overall, 276 patients were randomly assigned to receive ATRA-ATO or ATRA-CHT between October 2007 and January 2013. Results Of 263 patients evaluable for response to induction, 127 (100%) of 127 patients and 132 (97%) of 136 patients achieved complete remission (CR) in the ATRA-ATO and ATRA-CHT arms, respectively ( P = .12). After a median follow-up of 40.6 months, the event-free survival, cumulative incidence of relapse, and overall survival at 50 months for patients in the ATRA-ATO versus ATRA-CHT arms were 97.3% v 80%, 1.9% v 13.9%, and 99.2% v 92.6%, respectively ( P < .001, P = .0013, and P = .0073, respectively). Postinduction events included two relapses and one death in CR in the ATRA-ATO arm and two instances of molecular resistance after third consolidation, 15 relapses, and five deaths in CR in the ATRA-CHT arm. Two patients in the ATRA-CHT arm developed a therapy-related myeloid neoplasm. Conclusion These results show that the advantages of ATRA-ATO over ATRA-CHT increase over time and that there is significantly greater and more sustained antileukemic efficacy of ATO-ATRA compared with ATRA-CHT in low- and intermediate-risk APL.