Cladribine combined with high doses of arabinoside cytosine, mitoxantrone, and G-CSF (CLAG-M) is a highly effective salvage regimen in patients with refractory and relapsed acute myeloid leukemia of the poor risk: a final report of the Polish Adult Leukemia Group

Objectives:  Patients with primary refractory AML and with early relapses have unfavorable prognoses and require innovative therapeutic approaches. Purine analogs fludarabine (FA) and cladribine (2-CdA) increase cytotoxic effect of Ara-C in leukemic blasts and inhibit DNA repair mechanisms; therefore its association with Ara-C and mitoxantrone (MIT) results in a synergistic effect. In the current report, we present the final results of multi-center phase II study evaluating the efficacy and toxicity of CLAG-M salvage regimen in poor risk refractory/relapsed AML patients.
Methods:  The induction chemotherapy consisted of 2-CdA 5 mg/m², Ara-C 2 g/m², MIT 10 mg/m², and granulocyte-colony stimulating factor. In the case of PR, a second CLAG-M was administered. Patients in CR received consolidation courses based on high doses of Ara-C and MIT with or without 2-CdA.
Results:  One hundred and eighteen patients from 11 centers were registered; 78 primary resistant and 40 relapsed. Sixty-six patients (58%) achieved CR after one or two courses of CLAG-M, 49 (35%) were refractory, and 8 (7%) died early. WBC >10 g/L and age >34 yr were factors associated with increased risk of treatment failure. Hematological toxicity was the most prominent toxicity of this regimen. The probability of OS at 4 yr was 14% (95% CI 4–23%). OS was influenced by age, WBC >10 g/L and poor karyotype in both univariate and multivariate analyses. The probability of 4 yr DFS was 30% for all 66 patients in CR (95% CI 11–49%). Poor karyotype was the only factor associated with decreased probability of DFS.
Conclusions:  We conclude that CLAG-M is a well-tolerated and highly effective salvage regimen in poor risk refractory/relapsed AML.     

A multicenter,open, non-comparative,phase II study of the combination of cladribine (2-chlorodeoxyadenosine), cytarabine,and G-CSF as induction therapy in refractory acute myeloid leukemia - a report of the Polish Adult Leukemia Group (PALG)

OBJECTIVES: To evaluate the efficacy and toxicity of cladribine (2-chlorodeoxyadenosine, 2-CdA), cytarabine (Ara-C), and granulocyte-colony stimulating factor (G-CSF) (CLAG) regimen in refractory acute myeloid leukemia (AML) in the multicenter phase II study. METHODS: The induction chemotherapy consisted of 2-CdA 5 mg/m2, Ara-C2 g/m2, and G-CSF. In the case of partial remission (PR), a second CLAG was administered. Patients in complete remission (CR) received two consolidation courses based on HD Ara-C, mitoxantrone or idarubicine, with or without 2-CdA. RESULTS: Fifty-eight patients from 11 centers were registered; 50 primary resistant and eight early relapsed (CR1 < 6 months). CR was achieved in 29 (50%) patients, 19 (33%) were refractory, and 10 (17%) died early. Forty of 50 primary resistant patients received daunorubicin (DNR) and Ara-C as the first-line induction therapy (DA-7), 10 received additional 2-CdA (DAC-7). The CR rates after CLAG were 58% and 10%, respectively in each group (P = 0.015). Five of six patients with myelodysplastic syndrome (MDS)/AML achieved CR. Hematologic toxicity was the most prominent toxicity of this regimen. The overall survival (OS, 1 yr) for the 58 patients as a whole, and the 29 patients in CR were 42% and 65%, respectively. Disease-free survival (DFS, 1 yr) was 29%. Only first-line induction treatment with DA-7 significantly influenced the probability of CR after CLAG. None of the analyzed factors significantly influenced DFS and OS. CONCLUSION: CLAG regimen has significant anti-leukemic activity and an acceptable toxicity in refractory AML. The addition of 2-CdA to the first-line induction treatment may worsen the results of salvage with CLAG. The high CR rate in patients with MDS preceding AML deserves further observation.     

Autologous bone marrow transplantation for acute myeloid leukemia using busulfan plus etoposide as a preparative regimen

We have studied the use of a new preparative regimen for the treatment of patients in remission of acute myeloid leukemia (AML) with autologous bone marrow transplantation. Chemotherapy consisted of busulfan 1 mg/kg every 6 hours for 4 days (total dose, 16 mg/kg) on days -7 through -4 followed by an intravenous infusion over 6 to 10 hours of etoposide 60 mg/kg on day -3. Autologous bone marrow, treated in vitro with 100 micrograms/mL of 4-hydroperoxycyclophosphamide, was infused on day 0. We have treated 58 patients up to the age of 60 years, 32 in first remission, 21 in second or third remission, and 5 with primary refractory AML unresponsive to high-dose Ara-C, but achieving remission with aggressive salvage regimens. Of the first remission patients, there has been 1 treatment related death and 5 relapses. With median follow-up of 22 months, the actuarial relapse rate is 22% +/- 9% and disease-free survival is 76% +/- 9% at 3 years. Patients with favorable French-American-British (FAB) subtypes (M3 or M4 EO) did especially well, with no relapses seen in 15 patients observed for a median of 30 months. Actuarial relapse rate at 3 years was 48% for first remission patients with less favorable FAB subtypes. Of patients in second or third remission, there were 5 treatment related deaths and 4 relapses. With median follow-up of 22 months, the actuarial relapse rate is 25% +/- 11% and disease-free survival is 56% +/- 11% at 3 years. Four of five primary refractory patients died during treatment and 1 remains in remission with short follow-up. These preliminary data are very encouraging and, if confirmed, support the use of autologous purged bone marrow transplantation using aggressive preparative regimens as one approach to improve the outcome of adults with AML.     

Prognostic value of dysmyelopoietic features in de novo acute myeloid leukaemia: a report on 132 patients

The prognostic value of cytological features was assessed in 132 patients with de novo acute myeloid leukaemia (AML) treated by anthracycline-cytosine-arabinoside combination chemotherapy. Of these patients, 98 (75%) achieved complete remission (CR). A significantly lower CR rate was seen in patients with trilineage dysmyelopoiesis (TDMP) (P = 0.003), but not in patients with dyserythropoiesis and/or dysgranulopoiesis without abnormal megakaryocytes. Other unfavourable factors were age greater than 50 years (P = 0.042), leucocyte count greater than 100 x 10(9)/l (P = 0.006), M5 FAB subtype (P = 0.013), presence of complex cytogenetic rearrangement or abnormalities of chromosome 5 and/or 7 (P = 0.001). Bone marrow eosinophilia greater than 3% was significantly associated with a higher CR rate (P = 0.04). In a multivariate analysis, a low CR rate was best predicted by the presence of a complex karyotype or abnormalities of chromosome 5 and/or 7 (P = 0.0001) and by the TDMP (P = 0.0036). Median actuarial disease-free survival (DFS) was 24 months. Actuarial DFS was significantly shorter in patients with TDMP (P = 0.0001) and an elevated leucocyte count (P = 0.02). Age, FAB subtype and karyotype had no significant incidence on DFS. Presence of TDMP appears to be an important prognostic factor in de novo AML. This could be used as one of the guidelines to therapy.     

Phase II study of mitoxantrone and cytarabine in acute myeloid leukemia

Thirty-eight patients with acute myeloid leukemia (AML) were treated with mitoxantrone (Mto) combined with cytarabine (Ara-C). Five patients had received no previous treatment for acute myeloid leukemia, seven were refractory to treatment with standard first-line chemotherapy, eight had relapsed during treatment, and 18 had relapsed after treatment was stopped. Eleven of these relapses were early (within 6 months of stopping treatment). Mto was given for 5 days by iv bolus injection at a dose of 10 mg/m2 to 12 patients and at 12 mg/m2 to 26. Ara-C was given at a dose of 1 g/m2 twice daily by a 2-hour infusion for 3 days to 37 patients. One patient received Ara-C at a dose of 500 mg/m2 twice daily for 3 days. Toxicity was acceptable except for cerebellar toxicity in two patients, which was irreversible in one. Twenty-two patients (56%) achieved complete remission (CR), and four achieved partial remission (10%). Seventy-five percent of the patients who had relapsed during treatment and 58% of those who had relapsed after treatment was stopped achieved CR. Eleven patients remain in CR at a median time of 10 months (range, 3-17) after treatment. In five patients remissions have lasted greater than 1 year, one in a patient treated in second relapse and one in a patient treated in third relapse. Mto and Ara-C appear to be effective salvage therapy in acute myeloid leukemia and should be considered for incorporation into first-line induction regimens.     

Treatment of acute myelogenous leukaemia in patients aged 50–65: idarubicin is more effective than zorubicin for remission induction and prolonged disease-free survival can be obtained using a unique consolidation course

From December 1987 to June 1992, 251 patients aged 50–65 with de novo acute myelogenous leukaemia (AML) were recruited to a multi-institutional randomized clinical trial. Induction therapy consisted of Ara-C (200 mg/m², continuous infusion, days 1–7) with either zorubicin (ZRB) (200 mg/m², i.v., days 1–4) or idarubicin (IDR) (8 mg/m², i.v., days 1–5). Consolidation therapy consisted of a single course of intensive chemotherapy with high-dose Ara-C (3 g/m², 3 h infusion, q 12 h, days 1–4) and m-Amsa (100 mg/m²/d, i.v., days 5–7).
The complete remission (CR) rate was (73%) with Ara-C/IDR versus (60%) with Ara-C/ZRB ( P  = 0.033). In multivariate analysis, factors found to be significant in predicting CR were normal karyotype and treatment with IDR. With a median follow-up of 73 months, the median disease-free survival (DFS) duration of all CR patients and the probability of CR at 6 years were 17 months and 29%. In multivariate analysis the only factor associated with an increased DFS duration was a normal karyotype. The median event-free survival (EFS) duration for all evaluable patients and the median overall survival duration for all eligible patients were respectively 7 and 12 months without any difference between induction arms.
The study shows that in patients aged 50–65 idarabicin is more effective than zorubicin for remission induction. However, the type of anthracycline did not influence overall survival duration. Using a unique consolidation course, we observed a prolonged DFS which compares favourably with results obtained with more prolonged consolidation therapy or maintenance treatment.     

Cellular drug resistance profiles in childhood acute myeloid leukemia: differences between FAB types and comparison with acute lymphoblastic leukemia

Determining in vitro drug resistance may reveal clinically relevant information in childhood leukemia. Using the methyl-thiazol-tetrazolium assay, the resistance of untreated leukemic cells to 21 drugs was compared in 128 children with acute myeloid leukemia (AML) and 536 children with acute lymphoblastic leukemia (ALL). The differences between 3 French-American-British (FAB) types (M1/M2, M4, and M5) were also compared. AML was significantly more resistant than ALL to the following drugs, as noted by the median resistance: glucocorticoids (greater than 85-fold), vincristine (4.4-fold), L-asparaginase (6.9-fold), anthracyclines (1.8- to 3.4-fold), mitoxantrone (2.6-fold), etoposide (4.9-fold), platinum analogues (2.4- to 3.4-fold), ifosfamide (3.5-fold), and thiotepa (3.9-fold). For cytarabine and thiopurines, the median LC50 values (the drug concentration that kills 5% of the cells) were equal. Also, busulfan, amsacrine, teniposide, and vindesine showed no significant differences, but the numbers were smaller, and the median LC50 values were 1.3- to 5.2-fold higher in AML. None of the drugs demonstrated greater cytotoxicity in AML. FAB M5 was significantly more sensitive than FAB M4 to most drugs frequently used in AML, as indicated by the following ratios of median sensitivities: the anthracyclines (2.6- to 3.2-fold), mitoxantrone (12.5-fold), etoposide (8.7-fold), and cytarabine (2.9-fold). For etoposide and cytarabine (5.4- and 3.4-fold, respectively) FAB M5 was also significantly more sensitive than FAB M1/M2. FAB M5 was equally sensitive to L-asparaginase and vincristine as ALL. Only 15% of the AML samples were "intermediately" sensitive to glucocorticoids, mainly in FAB M1/M2. The poorer prognosis of childhood AML is related to resistance to a large number of drugs. Within AML, FAB M5 had a distinct resistance pattern. These resistance profiles may be helpful in the rational design of further treatment protocols. (Blood. 2000;96:2879-2886)     

Acute myelogenous leukaemia in older patients at St Bartholomew's Hospital: outcome with mitoxantrone and cytarabine

Elderly patients (age >60 years) with AML who are selected for curative treatment frequently receive anthracycline/cytarabine containing regimens. The anthracendione mitoxantrone (MTN) in combination with cytarabine (Ara-C) produces comparable complete remission rates to other regimens and may be less toxic. Over a 12 year period, 75 patients (median age 67 years, range 60-83 years) referred with newly diagnosed AML were treated with MTN and ara-C. MTN was administered at 12 mg/m(2)/day intravenously for three days in the first 26 patients, and 10 mg/m(2)/day intravenously for five days in a subsequent 49 patients. Ara-C was administered at a dose of 100 mg/m(2) twice daily intravenously for seven days. Complete remission (CR) was achieved in 34 out of 75 patients (45%). The median disease-free survival overall was 7.5 months (one month to nine and a half years). The median survival was one year for patients in whom CR was achieved, compared to four months in patients whom treatment failed (P=0.001). Age alone was predictive of achievement of CR, whilst presentation karyotype, serum LDH and patient age correlated with overall survival. These results confirm that although elderly patients have a poor outcome, prognostic factors can be identified that influence treatment outcome in this important group of patients.     

A multi-institutional comparison of mitoxantrone,etoposide, and cytarabine vs high-dose cytarabine and mitoxantrone therapy for patients with relapsed or refractory acute myeloid leukemia

Relapsed or refractory acute myeloid leukemia (R/R AML) has a poor prognosis and is best treated with salvage chemotherapy as a bridge to allogeneic stem cell transplant (alloSCT). However, the optimal salvage therapy remains unknown. Here we compared two salvage regimens; mitoxantrone, etoposide, and cytarabine (MEC) and mitoxantrone and high-dose Ara-C (Ara-C couplets). We analyzed 155 patients treated at three academic institutions between 1998 and 2017; 87 patients received MEC and 68 received Ara-C couplets. The primary endpoint was overall response (OR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of hospitalization, hematologic and nonhematologic toxicities, and success in proceeding to alloSCT. Baseline characteristics of the cohorts were well matched, though patients receiving Ara-C couplets had more co-morbidities (48.5% vs 33%; P = .07). OR was achieved in 43.7% of MEC and 54.4% of Ara-C couplets patients (P = .10). Ara-C couplets patients also trended towards a longer OS and PFS, more frequently proceeded to alloSCT (31% vs 54.4%; P = .003), and experienced less febrile neutropenia (94% vs 72%; P < .001) and grade 3/4 gastrointestinal toxicities (17.2% vs 2.94%; P = .005). No significant differences in other toxicities or median duration of hospitalization were noted. This is the first multi-institutional study directly comparing these regimens in a racially diverse population of R/R AML patients. Although these regimens have equivalent efficacy in terms of achieving OR, Ara-C couplets use is associated with significant reductions in toxicities, suggesting it should be used more frequently in these patients.     

Multicentre phase III trial on fludarabine, cytarabine (Ara-C), and idarubicin versus idarubicin, Ara-C and etoposide for induction treatment of younger, newly diagnosed acute myeloid leukaemia patients

Fludarabine plus cytarabine (Ara-C) and idarubicin (FLAI) is an effective and well-tolerated induction regimen for the treatment of acute myeloid leukaemia (AML). This phase III trial compared the efficacy and toxicity of FLAI versus idarubicin plus Ara-C and etoposide (ICE) in 112 newly diagnosed AML patients <60 years. Fifty-seven patients received FLAI, as the first induction-remission course, and 55 patients received ICE. Post-induction treatment consisted of high-dose Ara-C (HDAC). After HDAC, patients in complete remission (CR) received a second consolidation course (mitoxantrone, etoposide, Ara-C) and autologous stem cell transplantation (auto-SCT) or allogeneic (allo)-SCT, according to the age, disease risk and donor availability. After a single induction course, CR rate was 74% in the FLAI arm and 51% in the ICE arm (P = 0.01), while death during induction was 2% and 9% respectively. Both haematological (P = 0.002) and non-haematological (P = 0.0001) toxicities, especially gastrointestinal (i.e. nausea, vomiting, mucositis and diarrhoea), were significantly lower in FLAI arm. In both arms, relapses were more frequent in patients who were not submitted to allo-SCT. After a median follow-up of 17 months, 30% and 38% of the patients are in continuous CR in FLAI and ICE arm respectively. Our prospective randomised study confirmed the anti-leukaemic effect and the low toxic profile of FLAI as induction treatment for newly diagnosed AML patients.     

Time sequential chemotherapy for primary refractory or relapsed adult acute myeloid leukemia: results of the phase II Gemia protocol

BACKGROUND AND OBJECTIVE: High-dose cytarabine (HDAra-C), mitoxantrone and etoposide are the mainstay of several active regimens against relapsed or refractory acute myelogenous leukemia (AML). We designed a phase II study to assess the efficacy and side effects of a time sequential application of mitoxantrone plus intermediate-dose Ara-C followed by HDAra-C plus etoposide (GEMIA) in adult patients with refractory or relapsed AML. DESIGN AND METHODS: Patients with refractory or relapsed AML were eligible for GEMIA salvage therapy, which comprised mitoxantrone 12 mg/m2/day on days 1-3, Ara-C 500 mg/m2/day as a 24-hour continuous infusion on days 1-3, followed by HDAra-C 2 g/m2/12-hourly on days 6-8 and etoposide 100 mg/m2/12-hourly on days 6-8. Granulocyte colony-stimulating factor was started on day 14. In patients above the age of 55 the dose of Ara-C in the first sequence (days 1-3) was reduced to 250 mg/m2. RESULTS: Twenty patients were included, of whom 12 achieved complete remission after GEMIA (60%, 95% CI 40-80%), one was refractory and five died early from infection. Two additional patients achieved partial remission after GEMIA and complete remission after consolidation chemotherapy, for a final CR rate of 70% (95% CI 48-88%). Neutrophils recovered at a median of 27 days (range, 22-43) and platelets 46 days (range, 25-59) after the start of treatment. The median duration of remission was 133 days (range, 36-417+) whereas overall survival time lasted for a median of 153 days (range, 13-554+). Treatment-associated toxicity was comprised predominantly of infection, mucositis and diarrhea that reached World Health Organization grades III-V in 40%, 40% and 30% of patients, respectively. Despite the intention to rapidly proceed to a hematopoietic stem cell transplant in patients in remission, only five patients reached the transplant. INTERPRETATION AND CONCLUSIONS: The GEMIA time sequential chemotherapy regimen appears effective in obtaining remissions in refractory and relapsed adult AML. The high toxicity seen, however, suggests that its design is amenable to further improvements, especially in more elderly patients. Since remissions are short-lived, more innovative post-remission strategies are needed.     

Unrelated donor bone marrow transplantation using a chemotherapy-only preparative regimen for adults with high-risk acute myelogenous leukemia

Limited data are available for adults undergoing unrelated donor (URD) BMT for AML using chemotherapy-only preparative regimens. Previous studies incorporated irradiation, included adults and children, and excluded secondary leukemia. Herein we report long-term outcomes for adults with poor-prognostic AML receiving a novel regimen of busulfan (16 mg/kg), cytarabine (8,000 mg/m(2)), and cyclophosphamide (120 mg/kg) (BAC), followed by URD BMT. From June 1995 through October 2001, 45 adults were enrolled. Adverse features included unfavorable cytogenetics (49%), secondary AML (47%), leukemia at transplant (42%), and extramedullary disease (16%). At time of BMT, 23 were in remission (12 CR1) while 22 had leukemia. Four (9%) died early. Acute and chronic GVHD rates were 44 and 67%, respectively. Seventeen (38%) were disease-free 52 months post-BMT; 13 were leukemia-free (eight CR1) at transplant. Eleven relapsed. Three-year DFS and OS were 42 and 46%, respectively. DFS and OS were longer, and relapses less, for those in CR at time of BMT. Secondary leukemia, cytogenetics, cell dose, and GVHD did not influence outcome. In poor-risk AML, BAC provided cytoreduction comparable to reported TBI-containing regimens, when administered for URD BMT. With decreasing treatment-related mortality, it is justified to proceed early to URD BMT for patients with poor prognostic features.     

Chemotherapy for acute myeloid leukemias with cytosine arabinoside, daunorubicin, etoposide, and mitoxantrone may cause permanent oligoasthenozoospermia or amenorrhea in middle-aged patients

The aim was to follow-up gonadal functions in long-term survivors of acute myeloid leukemias (AML) after intensive chemotherapy based on high-doses of cytosine arabinoside (Ara-C) and anthracyclines in the study UHKT-911. Adult patients were treated with at least 3 cycles of chemotherapy including 1-3 courses of Ara-C 10 x 2000 mg/m2/12 h and daunorubicin (DNR) 2 x 45 mg/m2/d. Spermiologic examinations were performed in 7 men by the classic microscopic method and results were evaluated according to the WHOcriteria. Two patients (42- and 47-year-old) after DNR and Ara-C chemotherapy had nearly normal spermiologic findings. The semen of a 49-year-old patient contained normal numbers of spermatozoa with decreased velocity when examined 1 year after chemotherapy but 4 years later exhibited oligoasthenozoospermia. The patient received 4 cycles of Ara-C and DNR plus one cycle with etoposide 350 mg/m2 and mitoxantrone 30 mg/m2. Semen examination of two patients 55- and 59-year-old showed permanent oligoasthenozoospermia with only sporadic progressively motile spermatozoa which might not be compatible with fertilization by sexual intercourse. They received the same chemotherapy including cumulative doses of etoposide 500 mg/m2 and mitoxantrone 36 mg/m2. Semen of two patients after allogeneic bone marrow transplantation exhibited severe oligoasthenozoospermia with no motile spermatozoa. Permanent amenorrhea developed in two women (42- and 46-year-old) during chemotherapy with DNR, Ara-C, etoposide, and mitoxantrone which was not the case in three women (29-40 years old) treated without etoposide and mitoxantrone. Intensive chemotherapy with high-doses of Ara-C and DNR plus one cycle of etoposide and mitoxantrone may cause permanent gonadal dysfunction in middle-aged patients with AML.     

A multicenter, open, noncomparative, phase II study of the combination of cladribine (2-chlorodeoxyadenosine), cytarabine, granulocyte colony-stimulating factor and mitoxantrone as induction therapy in refractory acute myeloid leukemia: a report of the Polish Adult Leukemia Group

Purine nucleoside analogues, cladribine (2-chlorodeoxyadenosine, 2-CdA) and fludarabine (FAMP) are active agents in acute myeloid leukemias (AMLs). Synergistic interaction between FAMP or 2-CdA with cytarabine (cytosine arabinoside, Ara-C) has been demonstrated in preclinical and clinical studies. The current multicenter phase II study was initiated to evaluate the efficacy and toxicity of induction treatment consisting of 2-CdA (5 mg/m²), Ara-C (2 g/m²), mitoxantrone (MIT, 10 mg/m²) and granulocyte colony-stimulating factor (G-CSF) (CLAG-M) in refractory AML. In case of partial remission, a second CLAG-M was administered. Patients in complete remission (CR) received consolidation courses based on high-dose Ara-C and MIT with or without 2-CdA. Forty-three patients from five centers were registered: 25 primary resistant and 18 relapsed. CR was achieved in 21 (49%) patients, 20 (47%) were refractory and 2 (5%) died early. Hematologic toxicity was the most prominent toxicity of this regimen. The overall survival (OS; 1 year) for the 42 patients as a whole and the 20 patients in CR were 43% and 73%, respectively. Disease-free survival (1 year) was 68.6%. None of the analyzed prognostic factors influenced the CR and OS probability significantly. We conclude that CLAG-M regimen has significant antileukemia activity in refractory AML, which seems to be better than the activity of many other regimens. The toxicity of the treatment is acceptable.     

Sequential multiagent chemotherapy is not superior to high-dose cytarabine alone as postremission intensification therapy for acute myeloid leukemia in adults under 60 years of age: Cancer and Leukemia Group B Study 9222

The Cancer and Leukemia Group B (CALGB) study 9222 tested the hypothesis that treatment intensification of acute myeloid leukemia (AML) in first remission with multiple chemotherapy agents is superior to high-dose cytarabine (HiDAC) alone. We enrolled 474 patients younger than 60 years old with untreated de novo AML. Daunorubicin and cytarabine resulted in complete remission (CR) in 342 patients (72%), and 309 of these patients were randomized to receive one of 2 different intensification regimens. The first regimen consisted of 3 courses of HiDAC. The second regimen consisted of one course of HiDAC, a second course with etoposide and cyclophosphamide, and a third course with diaziquone and mitoxantrone. After a median follow-up time of 8.3 years, the median survival for all randomized patients was 2.8 years (95% CI, 1.9-6.8 years). There was no difference in disease-free survival (DFS) between the 2 regimens (P = .66). The median DFS was 1.1 years (95% CI, 0.9-1.7 years) for patients receiving HiDAC and 1.0 year (95% CI, 0.9-1.3 years) for those receiving multiagent chemotherapy. Cytogenetics was the only pretreatment characteristic prognostic for DFS, but there was no evidence of a differential treatment effect within cytogenetic risk groups. Toxicity was greater with multiagent chemotherapy. These 2 postremission regimens produced similar outcomes.     

Leukaemia cell drug resistance and prognostic factors in AML.

In 93 cases of acute myeloid leukaemia (AML) the extent to which prognostic factors mirrored the in vitro cellular chemotherapy resistance (to anthracyclines aclarubicin (Acla) and daunorubicin (Dau) as well as nucleoside analogue cytarabine (Ara-C)) was investigated using a 4-d MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay. We found that age at presentation and presence of secondary AML were significantly correlated to leukaemia cell Ara-C resistance. Thus, analysis of in vitro drug resistance data revealed that age at presentation and presence of secondary leukaemia were both independently correlated to cellular drug resistance, with older age being associated with higher Ara-C resistance in vitro (p=0.02 and 0.01 in univariate and multivariate analyses, respectively) and with secondary leukaemia being associated with higher Ara-C resistance (p=0.04 and 0.059 in univariate and multivariate analysis, respectively). Median LC-50 values (Ara-C) were: 178 ng/ml in paediatric cases, 356 ng/ml in younger adult cases, and 584 ng/ml in elderly (age > or = 60 yr) cases giving a resistance ratio between these age subgroups of 1:2.0:3.3. Median LC-50 values (Ara-C) was 381 ng/ml in de novo cases as opposed to 891 ng/ml (resistance ratio 1:2.3) in secondary cases. By contrast, cytogenetic findings, presenting leucocyte count, FAB-subtype, and gender were not consistently correlated to in vitro drug resistance to any of the three drugs. We conclude that at least two major adverse prognostic factors in AML (advanced age at presentation and presence of secondary leukaemia) are associated with increased leukaemia cell Ara-C resistance. High leucocyte count is not associated with increased cellular drug resistance towards Acla, Ara-C or Dau.     

Sequential intermediate-dose cytosine arabinoside and mitoxantrone for patients with relapsed and refractory acute myelocytic leukemia

Based on in vitro evidence of time-dependent synergistic kill of HL-60 leukemia cells exposed to Ara-C and mitoxantrone, 44 patients with relapsed or refractory AML and 3 with blastic CML were treated with a timed sequence of both drugs. There were 25 females and 22 males, with a median age of 53 (range 21-75). Of 31 patients with relapsed AML, 24 had one prior remission, 6 had two and 1 had three. Of these, 15 had failed a second reinduction attempt. Thirteen patients were primarily refractory to induction with Ara-C plus daunorubicin. Each dose of Ara-C, 500 mg/m2, was followed after 6 hr by mitoxantrone, 5 mg/m2, and the sequence was repeated four to six times (44-68 hr) in different cohorts of patients. All but two patients (one with blastic CML and one in relapse and refractory) are evaluable for response and toxicity. Of 16 patients in relapse without prior reinduction 7 achieved CR and 3 PR (62% response rate); there were 3 CR in the 14 patients who were in relapse and refractory (21% response rate) and 4 CR and 1 PR (35% response rate) in the 14 patients with primary anthracycline resistance. Five of seven patients previously exposed to mitoxantrone achieved CR. Response lasted from 2 to 42 months, with two patients alive and in continuing remission at 34 and 42 months. Average marrow recovery was seen after 25 days and time to remission was 30 days. Six patients died in induction (four from sepsis and two from the tumor lysis syndrome) and 21 had progressive disease. Chemotherapy was well tolerated with minor nausea and vomiting in 13 patients, moderate in 20, and severe in 2. Most patients did not have evidence of drug-induced mucositis: it was minor in 9 and moderate in 2. Renal dysfunction was attributable to the use of nephrotoxic antibiotics. Hepatic dysfunction was reversible and was minor in 10 patients, moderate in 13, and severe in 3. Sequential, timed administration of intermediate-dose Ara-C and mitoxantrone is an active and well-tolerated antileukemic regimen.     

High-dose cytosine arabinoside and amsacrine or mitoxantrone in relapsed and refractory acute myeloid leukaemia: a prospective randomized study

52 patients with refractory or relapsed acute myeloid leukaemia (AML) were randomly assigned to receive a combination of high-dose cytosine arabinoside (HD Ara-C), 3 g/m2/d and either mitoxantrone (MTX), 7 mg/m2/d (5 mg if older than 60 yr) or m-amsacrine (AMSA), 120 mg/m2/d (90 mg if older than 60 yr) for 5 d. The overall response rate was 50% and did not differ significantly in the two groups (46% for AMSA and 56% for MTX, p = 0.415). The median survival was 11 months (8 months for AMSA and 12 months for MTX, p = 0.326) and the median duration of complete remission (CR) was 11 months for AMSA and 12 months for MTX (p = 0.643). In relapsed patients, the only significant predictive factor for obtaining a complete response was the length of first complete remission. Patients with a first CR shorter than 6 months had a CR rate of 36% while it was 65% if the first CR lasted more than 6 months (p = 0.03). Severe (WHO grade III-IV) gastro-intestinal toxicity was more frequent in the AMSA group (27% vs 4%, p = 0.021). Treatment-related death occurred in 4 patients in the AMSA group and in 2 patients in the MTX group (p = 0.097). We conclude that neither of these two treatment modalities was shown to be superior in terms of CR rate and survival, with a better tolerance for MTX.     

Pretreatment leukaemia cell drug resistance is correlated to clinical outcome in acute myeloid leukaemia

In 85 adult patients diagnosed with acute myeloid leukaemia (AML) and treated at the same institution during a 5-yr period, the clinical significance of in vitro cellular drug resistance to the anthracyclines aclarubicin (Acla) and daunorubicin (Dau) as well as the nucleoside analogue cytarabine (Ara-C) was investigated using a 4-d MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay. In 59 patients of whom 40 were treated by the combination of Acla and Ara-C we found that leukaemia cell drug resistance towards Acla was higher (by a factor 2.80) in patients who failed to enter complete remission (CR) after the first cycle of induction chemotherapy as compared to patients who entered complete remission. The relationship was significant in univariate as well as multivariate analysis (p=0.02 and 0.03, respectively). By contrast, no in vitro single drug resistance values were consistently correlated to other parameters of clinical outcome (overall CR rate, overall survival (OS), or continuous complete remission (CCR)), whereas the combined Acla and Ara-C drug resistance profile (Acla/Ara-C DRP) was of prognostic significance to overall survival of all 85 patients (p=0.004) as well as to the CCR of 39 complete responders (p=0.04). These findings remained statistically significant in multivariate analyses correcting for other variables influencing clinical outcome including patient age, leukocyte count, karyotype, FAB-subtype, and presence/absence of secondary AML. We conclude that the in vitro drug resistance of leukaemia cells at time of disease presentation appears to be independent of prognostic significance to short- and long-term clinical outcome in AML.     

Clinical studies of acute myeloid leukemia in the Japan Adult Leukemia Study Group

Acute myeloid leukemia (AML) is the most common adult leukemia in Japan. The treatment for AML consists of induction, consolidation, and maintenance therapies. To improve outcomes in the treatment of AML, the Japan Adult Leukemia Study Group has conducted six studies in AML patients aged 15-64?years since 1987. In AML201 study, IDR (12?mg/m(2)/day for 3?days) or DNR (50?mg/m(2)/day for 5?days) in combination with Ara-C (100?mg/m(2)/day continuous infusion for 7?days) was established as the standard induction therapy, and four courses of combination chemotherapy using non-cross-resistant agents for non-core binding factor (CBF) AML or three courses of high-dose Ara-C for CBF AML was established as the standard consolidation therapy. The AML97 study showed that allo-HSCT from an HLA-identical sibling donor reduced relapse incidence and improved disease-free survival (DFS), but did not significantly impact overall survival (OS) in poor or intermediate risk patients. Despite these studies by JALSG, only about one-third of AML patients remain free of disease for more than 7?years. The JALSG is now conducting the AML209 study to adapt individual therapies according to genetic alterations.