Failure of three novel regimens to improve outcome for patients with relapsed or refractory acute myeloid leukaemia: a report from the Eastern Cooperative Oncology Group

The treatment of relapsed acute myeloid leukaemia (AML) remains unsatisfactory. We conducted a phase II randomized trial where patients received intermediate-dose cytarabine for 4 d followed by gemtuzumab ozogamicin on day 5 (Arm A), or combined with liposomal daunorubicin for 3 d (Arm B), or cytarabine given for 5 d combined with cyclophosphamide for 3 d and topotecan by continuous infusion for 5 d (Arm C). Eligible patients had primary refractory AML, a first relapse after a remission of <1 year, or a second or greater relapse. The primary objective of this trial was attainment of a conventional complete remission (CR) or a CR without platelet recovery (CRp) in at least 40% of patients. The CR/CRp rates for the 82 eligible patients were 3/26 (12%) in Arm A, 2/29 (7%) in Arm B, and 1/27 (4%) in Arm C. No patients who had relapsed within 6 months of initial CR or who had suffered multiple relapses responded. More than 95% of patients subsequently died of AML. No unexpected toxicities were encountered. We conclude that none of these three regimens were effective enough in the treatment of high-risk relapsed or refractory AML to warrant further study. This trial was registered at http://www.clinicaltrials.gov as #NCT00005962.     

Karyotypic analysis predicts outcome of preremission and postremission therapy in adult acute myeloid leukemia: a Southwest Oncology Group/Eastern Cooperative Oncology Group Study

The associations of cytogenetics with complete remission (CR) rates, overall survival (OS), and outcomes after CR were studied in 609 previously untreated AML patients younger than 56 years old in a clinical trial comparing 3 intensive postremission therapies: intensive chemotherapy, autologous transplantation (ABMT), or allogeneic bone marrow transplantation (alloBMT) from matched related donors. Patients were categorized into favorable, intermediate, unfavorable, and unknown cytogenetic risk groups based on pretreatment karyotypes. CR rates varied significantly (P <.0001) among the 4 groups: favorable, 84% (95% confidence interval [CI], 77%-90%); intermediate, 76% (CI, 71%-81%); unfavorable, 55% (CI, 48%-63%); and unknown, 54% (CI, 33%-74%). There was similar significant heterogeneity of OS (P <.0001), with the estimated relative risk of death from any cause being 1.50 (CI, 1.10-2.05), 3. 33 (CI, 2.43-4.55), and 2.66 (CI, 1.59-4.45) for the intermediate, unfavorable, and unknown risk groups, respectively, compared with the favorable group. In multivariate analyses, the effects of cytogenetic risk status on CR rate and OS could not be explained by other patient or disease characteristics. Among postremission patients, survival from CR varied significantly among favorable, intermediate, and unfavorable groups (P =.0003), with significant evidence of interaction (P =.017) between the effects of treatment and cytogenetic risk status on survival. Patients with favorable cytogenetics did significantly better following ABMT and alloBMT than with chemotherapy alone, whereas patients with unfavorable cytogenetics did better with alloBMT. Cytogenetic risk status is a significant factor in predicting response of AML patients to therapy; however, to tighten treatment correlates within genetically defined AML subsets, a significantly larger leukemia cytogenetic database is warranted.     

Acute megakaryocytic leukemia: the Eastern Cooperative Oncology Group experience

Acute megakaryocytic leukemia (AMegL) is a rare subtype of acute myeloid leukemia (AML) evolving from primitive megakaryoblasts. Because of its rarity and the lack of precise diagnostic criteria in the past, few series of adults treated with contemporary therapy have been reported. Twenty among 1649 (1.2%) patients with newly diagnosed AML entered on Eastern Cooperative Oncology Group (ECOG) trials between 1984 and 1997 were found to have AMegL. The median age was 42.5 years (range 18-70). Marrow fibrosis, usually extensive, was present in the bone marrow. Of the 8 patients who had cytogenetic studies performed, abnormalities of chromosome 3 were the most frequent. The most consistent immunophenotypic finding was absence of myeloperoxidase in blast cells from 5 patients. In the most typical 3 cases, the leukemic cells were positive for one to 2 platelet-specific antigens in addition to lacking myeloperoxidase or an antigen consistent with a lymphoid leukemia. Myeloid antigens other than myeloperoxidase and selected T-cell antigens (CD7 and/or CD2) were frequently expressed. Induction therapy included an anthracycline and cytarabine in all cases. Complete remission (CR) was achieved in 10 of 20 patients (50%). Two patients remain alive, one in CR at 160+ months. Resistant disease was the cause of induction failure in all but 3 patients. The median CR duration was 10.6 months (range 1-160+ months). The median survival for all patients was 10.4 months (range 1-160+ months). Although half of the patients achieved CR, the long-term outcome is extremely poor, primarily attributable to resistant disease. New therapeutic strategies are needed.     

Outcome after induction chemotherapy for older patients with acute myeloid leukemia is not improved with mitoxantrone and etoposide compared to cytarabine and daunorubicin: a Southwest Oncology Group study

Complete remission and long-term survival rates are low for older adults treated for acute myeloid leukemia (AML). Because of favorable phase 2 data using mitoxantrone and etoposide, we conducted a phase 3 study (SWOG-9333) in which patients over 55 years of age with previously untreated AML were randomized to receive mitoxantrone (10 mg/m(2) per day x 5) and etoposide (100 mg/m(2) per day x 5) [ME], or cytarabine (200 mg/m(2) per day x 7) and daunorubicin (45 mg/m(2) per day x 3) [AD] as induction therapy. The randomization was stratified by age, onset of leukemia, and multidrug resistance phenotype. Over a 4-year period, 328 eligible patients from 66 institutions were enrolled. The complete remission rate was 34% (95% confidence interval [CI] 26%-41%) for patients in the ME and 43% (CI 35%-51%) for patients in the AD treatment arm (one-tailed P value.96). The rates of resistant disease were 43% (CI 35%-51%) and 34% (CI 27%-42%), respectively, for the 2 treatment arms (one-tailed P value.95). The estimated overall survival at 2 years was 11% (CI 6%-15%) and 19% (CI 12%-25%) for patients randomized to ME and to AD induction therapy, respectively (one-tailed P value.99). After accounting for the independent prognostic factors associated with survival (karyotype, performance status, age, white blood cell count), exploratory analysis suggested there was a worse survival for patients who received ME compared with AD induction therapy (2-tailed P value.0066). We conclude that the results of our study do not demonstrate any benefit to the use of ME induction chemotherapy instead of AD in older patients with AML.     

A multicenter phase II trial of decitabine as first-line treatment for older patients with acute myeloid leukemia judged unfit for induction chemotherapy

Background

The treatment of acute myeloid leukemia of older, medically non-fit patients still poses a highly unmet clinical need, and only few large, prospective studies have been performed in this setting. Given the established activity of hypomethylating agents such as 5-aza-2''-deoxycytidine (decitabine) in myelodysplastic syndromes and acute myeloid leukemia with 20–30% bone marrow blasts, we investigated whether this drug is also active in patients with more than 30% blasts.

Design and Methods

To evaluate the efficacy and toxicity of decitabine in patients over 60 years old with untreated acute myeloid leukemia ineligible for induction chemotherapy, 227 patients (median age, 72 years), many with comorbidities, adverse cytogenetics and/or preceding myelodysplastic syndrome were treated with this hypomethylating agent. During the initial decitabine treatment (135 mg/m² total dose infused intravenously over 72 hours every 6 weeks), a median of two cycles was administered (range, 1–4). All-trans retinoic acid was administered to 100 patients during course 2. Fifty-two patients who completed four cycles of treatment subsequently received a median of five maintenance courses (range, 1–19) with a lower dose of decitabine (20 mg/m²) infused over 1 hour on 3 consecutive days every 4–6 weeks.

Results

The complete and partial remission rate was 26%, 95% CI (20%, 32%), and an antileukemic effect was noted in 26% of patients. Response rates did not differ between patients with or without adverse cytogenetics; patients with monosomal karyotypes also responded. The median overall survival from the start of decitabine treatment was 5.5 months (range, 0–57.5+) and the 1-year survival rate was 28%, 95%CI (22%,34%). Toxicities were predominantly hematologic.

Conclusions

Decitabine is well tolerated by older, medically non-fit patients with acute myeloid leukemia; myelosuppression is the major toxicity. The response rate and overall survival were not adversely influenced by poor-risk cytogenetics or myelodysplastic syndrome. Because of these encouraging results, randomized studies evaluating single-agent decitabine versus conventional treatment are warranted. The study is registered with the German Clinical Trials Registry, number DRKS00000069.     

A phase 2 study of lenalidomide monotherapy in patients with deletion 5q acute myeloid leukemia: Southwest Oncology Group Study S0605

Older acute myeloid leukemia (AML) patients with a chromosome 5q deletion have poor outcomes with conventional chemotherapy. This phase 2 study explored the safety and efficacy of single-agent lenalidomide in previously untreated older AML patients with del(5q) who declined standard chemotherapy. Patients were treated with lenalidomide 50 mg daily for 28 days as induction therapy and 10 mg daily for 21 days of a 28-day cycle as maintenance until disease progression or unacceptable toxicity. Among 37 evaluable patients, the median age was 74 years (range, 60-94), 21 (57%) were female, 19 (51%) had prior myelodysplastic syndrome, and 30 (81%) had pretreatment cytogenetic studies evaluated centrally. Six had isolated del(5q), 1 had del(5q) and +8, 23 had complex cytogenetics, and 7 others had del(5q) identified locally. Fourteen patients (38%) completed induction therapy: 7 patients died during induction therapy, 8 had disease progression, 7 had nonfatal adverse events, and 1 entered hospice. Eight patients started maintenance therapy. Five patients (14%) achieved a partial or complete response, 2 with isolated del(5q) and 3 with complex cytogenetics. Relapse-free survival was 5 months (range, 0-19). Median overall survival was 2 months for the entire population. In conclusion, lenalidomide as a single agent has modest activity in older del(5q) AML patients. Southwest Oncology Group Study S0605 is registered at www.clinicaltrials.gov as NCT00352365.     

Survival for older patients with acute myeloid leukemia: a population-based study

BackgroundAcute myeloid leukemia is the second most common leukemia among United States adults with a median age of 69 years. We investigated recent clinical practices related to treatments and disease outcomes in older patients with acute myeloid leukemia in the United States.ResultsAmong 5,480 patients with acute myeloid leukemia (median age 78 years, range 65-93), 38.6% received leukemia therapy within three months of diagnosis (treated group). Practice changed with 16.3% of treated patients receiving hypomethylating agents after 2004 when those agents became available. Median survival was two months in the untreated group versus six months in the treated group (P<0.01) with the biggest improvements seen in those aged 65-69 years (10 months vs. 4 months; P<0.01) and 70-74 years (8 months vs. 3 months; P<0.01). In 46 patients receiving allogeneic hematopoietic cell transplantation (0.8%), the median survival from diagnosis was 22 months.ConclusionsTherapy for leukemia improves overall survival in older acute myeloid leukemia patients. Based on their comorbidities, most patients up to 80 years of age should be considered for treatment. New therapies including hypomethylating agents and allogeneic hematopoietic cell transplantation are promising and must be compared with other chemotherapy regimens.Key words: acute myeloid leukemia, older patients, treatment, disease outcome, survival     

Final results of phase III trial in regionally advanced unresectable non-small cell lung cancer: Radiation Therapy Oncology Group, Eastern Cooperative Oncology Group, and Southwest Oncology Group

STUDY OBJECTIVES: The purpose of this phase III clinical trial was to test whether chemotherapy followed by radiation therapy resulted in superior survival to either hyperfractionated radiation or standard radiation in surgically unresectable non-small cell lung cancer. DESIGN: Patients were prospectively randomized to 2 months of cisplatin, vinblastine chemotherapy followed by 60 Gy of radiation at 2.0 Gy per fraction or 1.2 Gy per fraction radiation delivered twice daily to a total dose of 69.6 Gy, or 2.0 Gy per fraction of radiation once daily to 60 Gy. Patients were enrolled from January 1989 through January 1992, and followed for a potential minimum period of 5 years. SETTING: This trial was an intergroup National Cancer Institute-funded trial within the Radiation Therapy Oncology Group, the Eastern Cooperative Oncology Group, and the Southwest Oncology Group. PATIENTS: Patients with surgically unresectable non-small cell lung cancer, clinical stage II, IIIA, and IIIB, were required to have a Karnofsky Performance Status of > or = 70 and a weight loss of < 5% for 3 months before study entry. Four hundred ninety patients were registered on trial, of which 458 patients were eligible. CONCLUSION: Overall survival was statistically superior for the patients receiving chemotherapy and radiation vs the other two arms of the study. The twice-daily radiation therapy arm, although better, was not statistically superior in survival for those patients receiving standard radiation. Median survival for standard radiation was 11.4 months; for chemotherapy and irradiation, 13.2 months; and for hyperfractionated irradiation, 12 months. The respective 5-year survivals were 5% for standard radiation therapy, 8% for chemotherapy followed by radiation therapy, and 6% for hyperfractionated irradiation.     

Phase II trial of vorinostat and gemtuzumab ozogamicin as induction and post-remission therapy in older adults with previously untreated acute myeloid leukemia

Histone deacetylase inhibitors such as vorinostat enhance gemtuzumab ozogamicin efficacy in vitro. We, therefore, investigated vorinostat+gemtuzumab ozogamicin for adults aged 60 years and over with untreated acute myeloid leukemia. We stratified patients into 2 groups (group 1: patients aged ≥ 70 years and performance status 2-3; group 2: aged 60-69 years with performance status 0-3 or aged ≥ 70 years and performance status 0-1). Responses were monitored separately in group 2 patients with normal or favorable cytogenetics (group 2A) and other cytogenetics (group 2B). Among 31 patients, 6 (19.4%) achieved complete remission, and one (3.2%) achieved complete remission with incomplete platelet recovery; these patients had a higher median overall survival than non-responders (553 vs. 131 days, P = 0.0026). Response rates were: group 1, one of 10 (10.0%); group 2A, 6 of 13 (46.2%); and group 2B, none of 8 (0%). These data indicate that vorinostat+gemtuzumab ozogamicin has activity that is mostly confined to patients with normal karyotype disease. ClinicalTrial.gov: NCT00673153.     

A multicenter,phase II study of maintenance azacitidine in older patients with acute myeloid leukemia in complete remission after induction chemotherapy

Older patients with acute myeloid leukemia (AML) have poor outcomes, with median durations of complete remission lasting less than 1 year. Increased toxicity in older patients limits the delivery of standard consolidation therapies, such as allogeneic stem cell transplant or high‐dose cytarabine. Azacitidine, a nucleoside analog/DNA methyltransferase inhibitor, has demonstrated significant activity and favorable tolerability in patients unable to tolerate intensive induction chemotherapy; however, the role of azacitidine in the maintenance setting has not been fully evaluated. We undertook a pilot study of low‐dose subcutaneous azacitidine [50 mg/(m² day)] for 5 days every 4 weeks) in AML patients ≥60 years of age in first remission following standard induction therapy. The primary objective was to determine the 1‐year disease‐free survival (DFS); secondary objectives were to determine safety and tolerability. We enrolled 24 patients (median age 68, range 62–81 years), the majority of whom received anthracycline‐cytarabine induction regimens. From the time of first complete remission, the estimated 1‐year DFS was 50% and the median overall survival was 20.4 months. Thrombocytopenia and neutropenia were the most common grade 3/4 toxicities (50 and 58%, respectively). In our study population, maintenance therapy with subcutaneous azacitidine was safe and well tolerated. Am. J. Hematol. 90:796–799, 2015. © 2015 Wiley Periodicals, Inc.     

Prognosis of older patients with acute myeloid leukemia receiving either induction or noncurative treatment: a single-center retrospective study

Since few studies focus on prognostic factors in unselected elderly acute myeloid leukemia (AML) patients, a retrospective analysis of 138 consecutive patients aged >55 years (median age: 67, range: 56-89) with AML diagnosed at a single center over an 8-year period was performed: 69% had de novo AML and 31% secondary (s) AML; 67% of the patients were karyotyped. Of the patients, 73 (53%) were treated with standard induction therapy protocols and 65 (47%) received palliative treatment only. Univariate and multivariate analyses of the effects of the following factors on overall survival (OS) were performed: sex, age > or = vs <65 years, de novo vs sAML, serum (s) lactate dehydrogenase (LDH) > or = vs <400 U/l, leukocytes > or = vs <50,000/ microl, induction therapy, and karyotype. Additionally, in patients receiving induction therapy, complete remission (CR) rates and survival from CR were analyzed. CR rate was 47% [95% confidence interval (35%, 59%)], 53% (39%, 66%) in de novo AML, and 21% (5%, 51%) in sAML. After a median follow-up of 4 years, 130 deaths were observed (94%). In a univariate analysis, significant factors for longer OS were induction therapy, age <65 years, sLDH <400 U/l, and de novo AML. In a multivariate analysis, significant factors for longer OS were sLDH <400 U/l and induction therapy. However, the difference between treatment outcome may also be due to selection criteria not captured, such as performance status, comorbid conditions, wish of the patient, etc. The effects of intensive and nonintensive treatment in this patient group need to be investigated in prospective, randomized trials in which these clinical parameters of high relevance for treatment decisions in older patients are also considered.     

A phase 2 study of high-dose lenalidomide as initial therapy for older patients with acute myeloid leukemia

Older patients with acute myeloid leukemia (AML) have limited treatment options and a poor prognosis, thereby warranting novel therapeutic strategies. We evaluated the efficacy of lenalidomide as front-line therapy for older AML patients. In this phase 2 study, patients 60 years of age or older with untreated AML received high-dose (HD) lenalidomide at 50 mg daily for up to 2 28-day cycles. If patients achieved a complete remission (CR)/CR with incomplete blood count recovery (CRi) or did not progress after 2 cycles of HD lenalidomide, they received low-dose lenalidomide (10 mg daily) until disease progression, an unacceptable adverse event, or completion of 12 cycles. Thirty-three AML patients (median age, 71 years) were enrolled with intermediate (55%), unfavorable (39%), or unknown (6%) cytogenetic risk. Overall CR/CRi rate was 30%, and 53% in patients completing HD lenalidomide. The CR/CRi rate was significantly higher in patients presenting with a low (< 1000/μL) circulating blast count (50%, P = .01). The median time to CR/CRi was 30 days, and duration of CR/CRi was 10 months (range, 1- ≥ 17 months). The most common grades ≥ 3 toxicities were thrombocytopenia, anemia, infection, and neutropenia. HD lenalidomide has evidence of clinical activity as initial therapy for older AML patients, and further study of lenalidomide in AML and MDS is warranted. This study is registered at www.clinicaltrials.gov as #NCT00546897.     

Ethnicity and survival in childhood acute myeloid leukemia: a report from the Children's Oncology Group

We evaluated differences in outcome by ethnicity among children with acute myeloid leukemia (AML). We analyzed 791 children in the CCG 2891 trial and confirmed positive findings in 850 children in the CCG 2961 trial. Hispanic and black children treated with chemotherapy in CCG 2891 had significantly inferior overall survival (OS) from study entry compared with white children (37%+/- 9% vs 48%+/- 4% [P = .016] and 34% +/- 10% vs 48% +/- 4%, [P = .007], respectively). Significantly fewer black children had related donors. Analyses of CCG 2961 confirmed that black children had significantly decreased OS rates compared with white children (45% +/- 12% vs 60% +/- 4%; P = .007) The difference in OS rates between Hispanic and white children approached statistical significance (51% +/- 8% vs 60% +/- 4%; P = .065) Only 7.5% of black children on CCG 2961 had an available family donor. In conclusion, Hispanic and black children with AML have worse survival than white children. Access to chemotherapy, differences in supportive care or leukemia phenotype, and reduced compliance are unlikely explanations for this difference because therapy was given intravenously according to CCG protocols. Fewer black children than expected had an available family marrow donor.     

Continuous-infusion diaziquone in acute myeloid leukemia: a Southeastern Cancer Study Group trial

Diaziquone (AZQ) is a synthetic quinone with considerable activity against L1210 leukemia and potent myelosuppressive activity in man. To test the efficacy and toxicity of AZQ administered by continuous infusion, a phase II multi-institutional trial was undertaken by the Southeastern Cancer Study Group. Eligible adults with acute myeloid leukemia (AML) received AZQ at a dose of 28 mg/m2 daily by continuous infusion for 5 days. Patients failing to achieve complete remission received a second course utilizing the same dose and schedule. Of 25 evaluable patients with relapsed or refractory AML, three achieved complete response (12%) and two achieved partial response (8%). All patients experienced marked myelosuppression. Severe or life-threatening infection was observed in 15 (56%) patients. Clinical or postmortem evidence of central nervous system hemorrhage was encountered in three (12%) patients with severe refractory thrombocytopenia. Minimal nonhematologic toxicity was observed, suggesting that further studies of this agent in combination regimens and possibly for marrow transplantation preparation in patients with acute leukemia are warranted.     

Benefit of cyclosporine modulation of drug resistance in patients with poor-risk acute myeloid leukemia: a Southwest Oncology Group study.

Cyclosporine A (CsA) inhibits P-glycoprotein (Pgp)-mediated cellular export of anthracyclines at clinically achievable concentrations. This randomized controlled trial was performed to test the benefit of CsA addition to treatment with cytarabine and daunorubicin (DNR) in patients with poor-risk acute myeloid leukemia (AML). A total of 226 patients were randomly assigned to sequential treatment with cytarabine and infusional DNR with or without intravenous CsA. Remitting patients received one course of consolidation chemotherapy that included DNR with or without CsA as assigned during induction. Addition of CsA significantly reduced the frequency of resistance to induction chemotherapy (31% versus 47%, P =.0077). Whereas the rate of complete remission was not significantly improved (39% versus 33%, P =.14), relapse-free survival (34% versus 9% at 2 years, P =.031) and overall survival (22% versus 12%, P =.046) were significantly increased with CsA. The effect of CsA on survival was greatest in patients with moderate or bright Pgp expression (median 12 months with CsA versus 4 months for controls) compared to patients with absent or low Pgp expression (median 6 months in both arms). The frequency of induction deaths was 15% with CsA and 18% in controls. Steady-state serum concentrations of DNR (P =.0089) and daunorubicinol (P <.0001) were significantly higher in CsA-treated patients. Survival (P =.0003) and induction response (P =.028) improved with increasing DNR concentration in CsA-treated patients but not in controls, suggesting a targeted interaction by CsA to enhance anthracycline cytotoxicity. These results indicate that addition of CsA to an induction and consolidation regimen containing infusional DNR significantly reduces resistance to DNR, prolongs the duration of remission, and improves overall survival in patients with poor-risk AML.     

Phase II evaluation of an intensified induction therapy with standard daunomycin and cytarabine followed by high dose cytarabine for adults with previously untreated acute myeloid leukemia: a Southwest Oncology Group study (SWOG-9500)

Induction therapy for acute myeloid leukemia (AML) usually consists of 7 days of cytarabine at 100-200 mg/m(2)/day and an anthracycline. Such combinations produce complete response (CR) rates of 60-80% in patients with de novo AML. On the basis of a previous report, suggesting a higher CR rate using a regimen of standard daunomycin and cytarabine followed by 3 days of high-dose cytarabine (HDAC), 101 eligible patients received this regimen in a phase II trial. Sixty patients [59%, 95% confidence interval (CI) 49-69%] achieved a CR, and 10 patients died of infection during induction. Although cytogenetic risk group affected overall survival (P = 0.0016) and relapse-free survival (P = 0.0043), it had no impact on CR rate (P = 0.63). Patients received postremission therapy with repetitive courses of alternate day high-dose cytarabine; this was associated with considerable toxicity and the majority of patients could not receive all of the scheduled postremission therapy. The estimated median survival was 23 months (95% CI 15-34 months), and the estimated probability of surviving 5 years was 34% (95% CI 24-43%). The results of this intensive induction regimen were similar to that seen in previous trials and were not as promising as reported in the previous pilot study.     

Double induction strategy for acute myeloid leukemia: the effect of high-dose cytarabine with mitoxantrone instead of standard-dose cytarabine with daunorubicin and 6-thioguanine: a randomized trial by the German AML Cooperative Group.

Early intensification of chemotherapy with high-dose cytarabine either in the postremission or remission induction phase has recently been shown to improve long-term relapse-free survival (RFS) in patients with acute myeloid leukemia (AML). Comparable results have been produced with the double induction strategy. The present trial evaluated the contribution of high-dose versus standard-dose cytarabine to this strategy. Between March 1985 and November 1992, 725 eligible patients 16 to 60 years of age with newly diagnosed primary AML entered the trial. Before treatment started, patients were randomized between two versions of double induction: 2 courses of standard-dose cytarabine (ara-C) with daunorubicin and 6-thioguanine (TAD) were compared with 1 course of TAD followed by high-dose cytarabine (3 g/m2 every 12 hours for 6 times) with mitoxantrone (HAM). Second courses started on day 21 before remission criteria were reached, regardless of the presence or absence of blast cells in the bone marrow. Patients in remission received consolidation by TAD and monthly maintenance with reduced TAD courses for 3 years. The complete remission (CR) rate in the TAD-TAD compared with the TAD-HAM arm was 65% versus 71% (not significant [NS]), and the early and hypoplastic death rate was 18% versus 14% (NS). The corresponding RFS after 5 years was 29% versus 35% (NS). An explorative analysis identified a subgroup of 286 patients with a poor prognosis representing 39% of the entire population; they included patients with more than 40% residual blasts in the day-16 bone marrow, patients with unfavorable karyotype, and those with high levels of serum lactate dehydrogenase. Their CR rate was 65% versus 49% (p =.004) in favor of TAD-HAM and was associated with a superior event-free survival (median, 7 v 3 months; 5 years, 17% v 12%; P =.012) and overall survival (median, 13 v 8 months; 5 years, 24% v 18%; P =.009). This suggests that the incorporation of high-dose cytarabine with mitoxantrone may contribute a specific benefit to poor-risk patients that, however, requires further substantiation. Double induction, followed by consolidation and maintenance, proved a safe and effective strategy and a new way of delivering early intensification treatment for AML.