Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023467 (acute myeloid leukemia)
 35,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The increasing insights into the pharmacokinetics and the metabolism of cytosine arabinoside (AraC) have improved the rationale for its application in leukemia therapy and have led to a pharmacologically directed design of antileukemic treatment. The current study aims at adding to this approach by detecting differences in the intracellular metabolism of AraC 5'-triphosphate (AraCTP) between leukemic and normal mononuclear blood cells. Measurements of intracellular AraCTP levels were complemented by determinations of plasma AraC and AraU concentrations and were performed in 32 patients with acute myeloid leukemia undergoing combination therapy including either conventional (100 mg/m2 daily) or high-dose (1.0 or 3.0 g/m2 twice daily) AraC. Plasma AraC concentration showed a linear relationship to the applied AraC dose but did not correlate with intracellular AraCTP levels. During conventional-dose AraC therapy little interpatient variation was observed in AraCTP retention times in leukemic blasts from 5 patients with t1/2 values ranging from 1.70 to 2.50 h (median 2.14 h). In all cases AraCTP levels declined rapidly after the end of the AraC infusion. Substantial differences in AraCTP retention times were revealed, however, during 3 h infusions of either 1.0 or 3.0 g/m2 AraC in leukemic blasts from 10 patients with t1/2 values between 1.60 to 7.63 h (median 2.42 h). In addition, AraCTP levels declined in only one patient by > 10% within the first hour after the end of therapy and remained constant or even increased up to 1.5-fold in a post-treatment period of 1 to 2.5 h in the other nine cases. In contrast, AraCTP retention times were relatively uniform in normal mononuclear blood cells from 11 patients with t1/2 values of 3.34 to 5.29 h (median 3.85 h). More importantly, AraCTP levels dropped by > 10% within the first hour after the end of the high-dose AraC infusion in eight of 11 cases. A post-therapeutic increase > 10% was not observed in any patient. Similar findings emerged after in vitro exposure of normal bone marrow cells from six healthy volunteers to 20 mumol/l AraC for 3 h revealing a > 10% decrease of intracellular AraCTP within the first post-treatment hour in all cases with AraCTP retention times of 2.29 to 8.63 h (median 3.20 h). These differences in AraCTP pharmacokinetics between leukemic and normal blood cells may provide the basis for a modified timing of AraC administration with the aim of selectively maintaining cytotoxic AraCTP levels in leukemic blasts while allowing an intermittent drop of AraCTP levels in normal cells.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Differences in the intracellular pharmacokinetics of cytosine arabinoside (AraC) between circulating leukemic blasts and normal mononuclear blood cells. 145 72

The prognosis and long-term results of a group of 57 acute megakaryoblastic leukaemia (M7-AML) patients was analysed from a multicentre perspective. Ages ranged from 4 to 83 years, median 49 years; 30 were males and 27 were females. The median follow-up time was 7 months, range 1-24 months. Early exits occurred in 12 cases, their median age being 71 years. Forty-five patients were treated with combined aggressive chemotherapy (CT) (n = 26) or low-dose cytarabine (LD-AraC) (n = 19). The following results were obtained with combined CT or AraC, respectively. Complete remission (CR) rates were 73% and 84%, 12-month survival (SV) were 37% and 26%, 24-month SV were 12% and 11%, median SV 10 and 4 months, and relapse rates (RR) were 68% and 94%. These differences were not statistically significant. Irrespective of the treatment modality, the results were better for children (n = 10) than for adults (n = 35): RR rates were 90% and 74%, median SV: 7 and 5 months, 12-month SV: 40% and 22%, 24-month SV; 30% and 9%, and RR: 78% and 81%, respectively; these differences also were not statistically significant. In addition, a literature review of 42 patients from 18 previous reports is presented, including seven cases treated with allogeneic bone marrow transplantation (BMT). The best results were obtained with BMT: 12 and 24 month SV was 86% and the RR was 0%. On the above-mentioned basis, we feel that children and young adults with M7-AML should be offered BMT. In patients over 60 years old or not eligible for aggressive chemotherapy or BMT, an interesting possibility would be the use of LD-AraC which allows a high CR rate, followed by a classical consolidation regimen in order to prevent early relapses.
 ...
PMID:Long-term treatment results for acute megakaryoblastic leukaemia patients: a multicentre study. 148 53

The use of new drugs in the treatment of AML could dramatically increase the cost of induction chemotherapy. To evaluate the cost-effectiveness of such new drugs, the overall cost to achieve complete remission (CR) with treatments including these drugs has to be compared to the cost of the daunorubicin-cytosine arabinoside (DNR-AraC) association, considered as the reference treatment. A retrospective analysis of charts from 15 patients treated with DNR-AraC was used to identify 228 items of cost, including general cost, diagnostic, supportive care, and chemotherapy. Eleven patients underwent CR after one course of chemotherapy for a cost of US$16,701 +/- 4451, and four patients achieved CR after two courses for a cost of US$37,130 +/- 4923. The chemotherapy represented only 1.4% of the total cost, supportive care 25% and general cost 56%. According to these data, the projective cost of a treatment with mitoxantrone instead of DNR was simulated in 40 untreated patients with AML. The better rate of CR obtained after one course of chemotherapy leads to a saving of 9% (US$1261) per patient, despite the higher cost of chemotherapy. Cost-effectiveness evaluation should be included in the clinical study of trials with new drugs.
 ...
PMID:Cost of complete remission induction in acute myeloblastic leukemia: evaluation of the cost-effectiveness of a new drug. 162 92

Twenty-two patients with acute myeloid leukemia (AML), having a median age of 48.3 years (range 26-70; 10 male, 12 female), were treated with 4'-(9-acridinylamino) methanesulphon-m-anisidide (m-AMSA) 100 mg/m2 and cytosine arabinoside (AraC) 2 x 1000 mg/m2i.v. on days 1-5. There were 2M1,8 M2, 9 M4, 2M4 Eo, and 1 M5a. Of these, 12 achieved a complete remission, 3 a partial remission and 6 did not respond. The median remission duration was 9.0 months and the median overall survival 8.1 months. Side-effects of induction consisted mainly of haematological toxicity and infections with a median duration of WHO-grade-4 granulopenia and thrombopenia of 20 and 28 days respectively. Organ toxicity was mild with mucositis and cutaneous and liver toxicity being experienced by only a few patients. There was one treatment-related death. Five-day m-AMSA and intermediate-dose AraC is an easy-to-handle condensed treatment schedule with tolerable toxicity. Its effectiveness in relapsed and refractory AML is comparable to combinations of high-dose AraC with m-AMSA, anthracyclines or etoposide.
 ...
PMID:Five-day 4'-(9-acridinylamino)methanesulphon-m-anisidide and intermediate-dose cytosine arabinoside in high-risk relapsing or refractory acute myeloid leukemia. 189 Jan 42

Pharmacologic and immunologic methods of ex-vivo bone marrow (BM) purging for acute nonlymphocytic leukemia (ANLL) were combined to augment the effect of either method alone. Etoposide (VP16; 20 to 30 micrograms/mL) with or without cytosine arabinoside (Ara C; 10 mg/mL) was used in tandem with the anti-CD33 monoclonal antibody (MoAb), MY9, chosen because CD33 is found on the stem cell pool in the majority of patients with ANLL. The agents were tested singly or sequentially, with a 1-hour incubation of the drugs preceding complement-mediated lysis using MY9. VP16 combined with Ara C killed up to 3.9 +/- 0.3 and 5.11 +/- 0.4 logs of the human ANLL cell lines HL60 and K562 at drug concentrations that killed only 1.2 +/- 0.1 logs of normal committed granulocyte/macrophage stem cells (CFU-GM). Adding a single exposure of the MY9 and complement (C') to the drug-treated cells, greater than 5.4 logs of HL60 were killed. Similar to other pharmacologic agents, no differential kill for clonagenic leukemic cells (colony-forming unit-leukemia; CFU-L) from patients with ANLL was seen for drug only treated blasts versus normal CFU-granulocyte-macrophage (CFU-GM), with less than 1 log CFU-L kill at drug concentrations that spared 1 log of CFU-GM. Similarly, only 1.1 +/- 0.3 logs of ANLL CFU-L were eliminated using MY9 and C'. However, with the sequential VP16/Ara C----MY9 + C' treatment, synergy was demonstrated and 2.6 +/- 0.3 logs of CFU-L were eliminated. Because CD33 is also found on the normal CFU-GM pool, two-stage long-term BM cultures were performed to determine pluripotent stem cell elimination by the drug/MoAb purging combination. No difference of CFU-GM or BFU-E production at 4 to 6 weeks of culture for VP16/Ara C, MY9 + C', or VP16/AraC----My9 + C' treated cells was seen compared with untreated controls indicating sparing of early progenitor cells. Sequential ex vivo treatment of human ANLL CFU-L with VP16/Ara C followed by complement-mediated lysis using MY9 synergistically kills CFU-L while sparing early normal hematopoietic progenitor cells, and thus may be a more effective way to purge BM than either alone.
 ...
PMID:Anti-CD33 monoclonal antibody and etoposide/cytosine arabinoside combinations for the ex vivo purification of bone marrow in acute nonlymphocytic leukemia. 198

We treated 47 adult patients with de novo myelodysplastic syndrome (MDS) by an anthracycline-AraC regimen. Median age was 54, and M/F 1.3. At diagnosis, 26 patients had refractory anaemia with an excess of blasts in transformation (RAEB-T) three had refractory anaemia (RA), 11 had refractory anaemia with excessive blasts (RAEB) and seven had chronic myelomonocytic leukaemia (CMML). Treatment was started within 3 months of diagnosis in 30 patients, and after more than 3 months in the 17 remaining patients. At the onset of treatment, 16 patients had progressed to acute myeloid leukaemia (AML). Twenty-two patients (47%) reached complete remission (CR), 10 (21%) had hypoplastic death and 15 (32%) had resistant disease. Median actuarial disease-free interval was 11 months. Median actuarial survival was 14 months from diagnosis and 10 months from the onset of treatment. A significantly higher CR rate was found in patients with RAEB-T at diagnosis (69% v 19% in patients with other FAB subtypes: P = 0.008), and in patients treated within 3 months of diagnosis. Using multivariate analysis, RAEB-T at diagnosis emerged as the most powerful prognostic factor of CR achievement. Karyotype was the only significant prognostic factor of disease-free interval, with a median of 16.5 months in patients with normal karyotype versus 4 months in patients with normal findings (P = 0.018). A subgroup of 15 patients with RAEB-T at diagnosis and normal karyotype, who had a CR rate of 80% and a median actuarial disease-free interval of 18 months, could be identified. Our results confirm that, overall, intensive chemotherapy has limited efficacy in MDS, especially when compared with allogeneic bone marrow transplantation (BMT). Relatively favourable results were obtained in our patients with RAEB-T at diagnosis, however, particularly those with normal karyotype. In that subgroup, intensive chemotherapy may be recommended, especially before BMT, as a high risk of relapse after BMT in patients with RAEB-T allografted as first line therapy has been reported.
 ...
PMID:Prognostic factors in adult de novo myelodysplastic syndromes treated by intensive chemotherapy. 202 75

Cytosine arabinoside (AraC) is one of the most active drugs in the treatment of acute leukemias and is widely applied at all phases of therapy. In spite of extensive clinical and experimental investigations, its intracellular metabolism and especially its mechanism of action are still not fully elucidated. Controversy also continues about the most appropriate way and dose of administration; which differs by more than 100 fold in clinical studies ranging from low-dose, over standard and intermediate dose regimens, to high-dose protocols. The present review is focused on the role and place of high-dose AraC treatment in acute myeloid leukemia (AML). Based on available clinical and experimental data, the following conclusions can be drawn: Not considering possible but not yet demonstrated beneficial long-term effects, the incorporation of high-dose AraC into induction therapy has not resulted in an improvement of overall remission rate, with the possible exception of patients with slow initial cytoreduction after a first course of conventional treatment. Promising results, however, emerge from high-dose AraC-based consolidation protocols, which need confirmation in prospectively randomized comparative trials. In relapsed and refractory AML, higher than conventional doses undoubtedly enhance the efficacy of AraC salvage therapy. The question of whether the antileukemic activity of intermediate-dose regimens with 500-1,000 mg/m2 AraC is equivalent to that of high-dose protocols applying 2,000-3,000 mg/m2 AraC, however, remains open but may soon be answered by ongoing controlled clinical and pharmacologic investigations.
 ...
PMID:Cytosine arabinoside in the treatment of acute myeloid leukemia: the role and place of high-dose regimens. 203 74

The Children's Cancer Study Group instituted a pilot study to investigate the use of high doses of cytosine arabinoside (AraC) in the intensification phase of treatment for acute nonlymphocytic leukemia (ANLL). Patients achieving remission and not eligible for allogeneic bone marrow transplantation were treated with four doses of high-dose AraC and L-asparaginase. These drugs were repeated either on or after 28 days (q28 days), after recovery of hematologic parameters (for the first 49 patients entered onto this trial); or after 7 days (q7 days), despite dropping blood counts (for the last 53 patients enrolled). After completing an additional 3 months of intensification therapy, patients were then allocated by physician choice to either discontinue therapy or receive 18 28-day cycles of maintenance therapy, including the daily administration of 6-thioguanine. Despite three deaths associated with the toxicity of the aggressive (q7 days) AraC timing, patients receiving this approach demonstrated equal or better disease-free survival from the end of induction (55% versus 42% actuarially at 3 years [P = 0.52]). Maintenance therapy appeared to play no role in improving outcome for people who received the aggressive timing of AraC cycles. Fifty-nine percent were alive disease free actuarially at 3 years from the decision to not give maintenance therapy (n = 27) compared with 62% for those receiving maintenance therapy (n = 16; P = 0.49). On the other hand, patients who received the less aggressive AraC intensification timing (q28 days) had an improved survival rate if maintenance therapy was administered (n = 17) (65% versus 39% for patients not receiving maintenance therapy [n = 24] at 3 years [P = 0.07]). Maintenance therapy therefore may not improve outcome in patients receiving aggressive timing of high-dose AraC but may be important in less intensive postremission regimens in childhood ANLL.
 ...
PMID:The role of timing of high-dose cytosine arabinoside intensification and of maintenance therapy in the treatment of children with acute nonlymphocytic leukemia. 220 52

The present randomized trial addressed the pending question whether cytosine arabinoside (AraC) should be given at high or intermediate dose to patients with relapsed or refractory acute myeloid leukemia. Based upon the previously established regimen of the sequential administration of AraC and mitoxantrone (S-HAM) patients below 60 years of age were randomized to receive AraC at either 3.0 g/m2 vs. 1.0 g/m2 per dose while older patients were randomly assigned to either 1.0 g/m2 or 0.5 g/m2 AraC. Concurrent pharmacokinetic analyses were performed to determine the plasma AraC pharmacokinetics as well as the intracellular AraCTP peak concentrations and retention times. At the present stage 65 patients are evaluable for response and toxicity. Complete remissions were achieved at similar frequencies for patients treated with 3.0 g/m2 or 1.0 g/m2 AraC with 56% and 50%, respectively. Reasons for failure were different, however, with a higher incidence of resistant disease in patients treated with 1.0 g/m2 AraC and more early deaths in the higher dose treatment group. Pharmacokinetic studies indicated a homogeneous distribution of AraC plasma concentrations but a substantial interpatient variability for intracellular AraCTP peak concentrations and retention times.
 ...
PMID:High-dose versus intermediate-dose cytosine arabinoside in combination with mitoxantrone for the treatment of relapsed and refractory acute myeloid leukemia--preliminary clinical and pharmacological data of a randomized comparison. 227 43

Aclacinomycin is a member of naturally occurring anthracyclines having three sugar moieties in the molecule. It showed antitumour activity on various mouse and rat tumours. Combination therapy with AraC etc. gave remarkable clinical results on acute myeloid leukaemia. Aclacinomycin strongly inhibits RNA synthesis of the tumour cells. It has lower cardiac toxicity than adriamycin and no mutagenicity. THP-Adriamycin is a derivative of adriamycin designed from the structure of baumycins. It showed stronger effects than adriamycin in inhibiting many mouse tumours such as L1210 and P388 leukaemia, B16 melanoma and colon 38 adenocarcinoma. THP-Adriamycin is rapidly taken up by both adriamycin-sensitive and resistant leukaemic cells. Its level of cardiac toxicity is as low as that of aclacinomycin. Ditrisarubicins are new naturally occurring anthracyclines isolated from Streptomyces having six sugar moieties in the molecule. Ditrisarubicin has a potent cytostatic and antitumour activities on adriamycin resistant mouse leukaemia. Its binding constant to DNA is extremely high compared with other anthracyclines.
 ...
PMID:Experimental studies of new anthracyclines: aclacinomycin, THP-adriamycin and ditrisarubicins. 244 79


1 2 3 4 5 6 7 8 9 10 Next >>