High-dose ara-C and etoposide in refractory or relapsing acute leukemia

Timed-sequential chemotherapy as induction and/or consolidation regimen for younger adults with acute myelogenous leukemia

Increasing the intensity of induction chemotherapy has generated considerable recent interest in the treatment of acute myeloid leukemia. Achieving complete remission is a sine qua non condition for prolonged disease-free survival and may affect long-term outcome. In this setting, administering a repeat course of induction shortly after completion of the first course, known as timed-sequential chemotherapy (TSC), has been tested and may lead to an improved long-term outcome. Whether these results are due to the biologic recruitment of cell cycle-specific agents is unknown. However, this strategy to intensify induction may lead to more profound myelosuppression and to potential toxicities. Here we review the results of timed-sequential chemotherapy, used as induction regimen in de novo, relapsed or refractory AML or used as post-remission therapy, and compare them with those from other types of regimens.

A phase Ib GOELAMS study of the mTOR inhibitor RAD001 in association with chemotherapy for AML patients in first relapse

The mTORC1 signaling pathway is constitutively activated in almost all acute myelogenous leukemia (AML) patients. We conducted a phase Ib trial combining RAD001 (everolimus), an allosteric inhibitor of mTORC1, and conventional chemotherapy, in AML patients under 65 years of age at first relapse (clinical trial NCT 01074086). Increasing doses of RAD001 from 10-70 mg were administrated orally on days 1 and 7 (d1 and d7) of a 3+7 daunorubicin+cytarabine conventional induction chemotherapy regimen. Twenty-eight patients were enrolled in this trial. The treatment was well tolerated with <10% toxicity, mainly involving the gastrointestinal tract and lungs. In this phase Ib trial, the RAD001 maximum tolerated dose was not reached at 70 mg. Sixty-eight percent of patients achieved CR, of which 14 received a double induction. Eight subsequently were intensified with allogeneic-stem cell transplant. Strong plasma inhibition of P-p70S6K was observed after RAD001 administration, still detectable at d7 (d7)at the 70 mg dosage. CR rates in patients with RAD001 areas under or above the curve median were 53% versus 85%. A 70 mg dose of RAD001 at d1 and d7 of an induction chemotherapy regimen for AML has acceptable toxicity and may improve treatment.

Early stem cell transplantation for refractory acute leukemia after salvage therapy with high-dose etoposide and cyclophosphamide

Primary refractory acute leukemia (AL) has a poor prognosis, although some patients can be salvaged with allogeneic stem cell transplantation (SCT). Induction of complete remission (CR) with conventional chemotherapy before SCT may improve outcome in this patient population. Between March 1991 and October 2003, 59 adults with primary refractory AL were treated with continuous-infusion etoposide (VP) 2.4 to 3.0 g/m(2) followed by cyclophosphamide (Cy) 6.0-7.2 g/m(2) intravenously over 3 to 4 days with the intention of proceeding to SCT in CR1. Forty-two patients had acute myelogenous leukemia (AML), 13 patients had acute lymphoblastic leukemia (ALL), and 4 patients had acute biphenotypic leukemia. The most frequent nonhematologic toxicities were oral mucosal, gastrointestinal, and hepatic toxicities (44%, 20%, and 15% of patients, respectively). Thirty-two (57%) of 56 evaluable patients entered CR1 with a median time to platelet and neutrophil recovery of 22 and 26 days, respectively. CR1 rates were similar in AML (54%) and ALL/acute biphenotypic leukemia (67%; P = .52), and analysis of baseline characteristics did not reveal any predictors of response to VP/Cy. Twenty-nine of 32 CR1 patients subsequently underwent SCT (24 allogeneic and 5 autologous). Estimated 5-year event-free survival (EFS) and overall survival for the entire cohort are 23% and 26%, respectively. In the allogeneic SCT group, 5-year EFS was 52% for AML patients and 14% for ALL patients (P = .04), and only male sex was predictive of a favorable outcome (P = .03). VP/Cy is able to induce CR1 in most patients with primary refractory AL with an acceptable toxicity profile. Subsequent allogeneic SCT can lead to long-term EFS in a significant proportion of patients.

High-efficiency retroviral gene transfer into murine high-proliferative-potential cells cycle-activated by cytosine arabinoside

We investigated cytosine arabinoside (Ara-C) as a potential agent for in vivo cycle activation of hematopoietic progenitors for the purpose of retroviral-mediated gene transfer. C57Bl mice were treated intraperitoneally with one of three regimens of Ara-C: a single 1,750 mg/kg dose (regimen 1), a 1,750 mg/kg dose on day 0, and a 1,500 mg/kg dose on day 2 (LD50) (regimen 2), or a 1,750 mg/kg dose on day 0 and a 1,500 mg/kg dose on day 3 (regimen 3). The high-proliferative-potential cells (HPPC)/10(5) cells were 47.0 +/- 7.5 pretreatment. The post-treatment HPPC cloning efficiencies were 40.6 +/- 3.4, 83.6 +/- 6.1, and 20.4 +/- 3.2 HPPC/10(5) cells on days 1, 2, and 4, respectively, with regimen 1; 60.0 +/- 7.9, 194.0 +/- 9.6, and 103.0 +/- 11.0 HPPC/10(5) cells 1, 2, and 4 days after the second Ara-C dose, respectively, with regimen 2; and 266 +/- 13.4, 132 +/- 23.9, and 118.0 +/- 5.7/10(5) cells 1, 2, and 4 days after the second Ara-C dose, respectively, with regimen 3. The transduction efficiency of HPPC from untreated animals with N2 viral supernatant was 4.9 +/- 5.8%.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of relapsed or refractory adult acute lymphocytic leukemia

Sixty-six adult patients were treated for relapsing or refractory acute lymphocytic leukemia (ALL). The induction treatment consisted in a (1) first phase with vindesine 3 mg/m2 intravenously (IV) on days 1, 8, and 15; daunorubicin 45 mg/m2 IV on days 1, 8, and 15; erwinia-asparaginase 10,000 U/m2 IV on days 7, 8, 14, and 15; and prednisone 60 mg/m2 orally on days 1 to 21 and a (2) second phase with cytarabine 3000 mg/m2 as a 3-hour infusion two times a day on days 1 to 4 (in patients greater than 50 years of age we used 1000 mg/m2), and etoposide 100 mg/m2 IV on days 1 to 5. Side effects of induction Phase I were predominantly hematologic with subsequent infections. In Phase II, some patients additionally had gastrointestinal, cutaneous, ocular, and hepatic toxicity. Five patients died during Phase I and another died during Phase II. Five of these patients had T-cell ALL. Thirty-four (64%) of 54 patients in their first relapse had a complete remission (CR) with a median disease-free survival (DFS) of 2.9 months. The median overall survival (OAS) was 6.6 months. Seven of 12 patients with primary refractory disease, a second relapse, or relapse after bone marrow transplantation (BMT) had a CR. The CR rate and survival after first relapse was significantly better in patients with a preceding CR of more than 18 months compared with those with a shorter preceding remission. The leukocyte count was a second significant but not independent risk factor. There was a negative correlation between the leukocyte count and the duration of the preceding CR. The duration of the preceding CR was the major prognostic factor for survival in multivariate analysis. Twenty-two patients received BMT. None of nine patients with autologous BMT is alive and disease-free; 5 of 13 who underwent allogeneic BMT are. It was concluded that this treatment efficiently induced remission with tolerable toxicity. The remission duration should be improved by optimized consolidation treatment.