Intermediate-dose Ara-C Research Articles

Mitoxantrone, Etoposide and Intermediate-dose Ara-C (MEC) for the Treatment of Acute Myelogenous Leukemia (AML)

Mitoxantrone, Etoposide and Intermediate-dose Ara-C (MEC) for the Treatment of Acute Myelogenous Leukemia (AML)

Five-day 4′-(9-acridinylamino)methanesulphon-m-anisidide and intermediate-dose cytosine arabinoside in high-risk relapsing or refractory acute myeloid leukemia

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.

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.

Intermediate and high dose Ara-C and m-AMSA for remission induction and consolidation treatment of patients with acute myeloid leukemia: an EORTC leukemia cooperative group phase II study

Seventy-nine patients (aged 17–76 years) with acute myelogenous leukemia in first (56) or second (3) relapse, primary refractory leukemia (15) or leukemia occurring as secondary malignancy that developed after a preleukemic phase (3) or after another tumor (2) were given remission induction therapy consisting of cytosine arabinoside (Ara-C, 1 g/m 2 as a 2-h infusion every 12 h for 6 days) and m-AMSA (120 mg/m 2 , i.v. on days 5, 6, 7). In total 45 patients (57%) achieved complete remission. Younger patients and those with a relatively low initial white blood cell count, a good performance status or in first relapse had a higher response rate. Thirty-five patients were given one or two courses of consolidation chemotherapy consisting of Ara-C (3 g/m 2 as a 2-h infusion every 12 h for 4 days) and m-AMSA (120 mg/m 2 i.v. on day 5). Three patients received on allogeneic bone marrow graft after the induction courses and four patients received an autologous bone marrow transplantation after consolidation therapy. The median of the disease-free survival curve was 21 weeks. The median duration of survival was 25 weeks. The response rate for this intermediate dose Ara-C regimen is satisfactory and does not differ from that reported for high dose Ara-C. The impact of consolidation chemotherapy in bad risk acute myelogenous leukemia is questionable.

Saturation of ara-CTP accumulation during high-dose ara-C therapy: pharmacologic rationale for intermediate-dose ara-C.

been identified in patients with relapsed acute leukemia28 and similar, although less striking, correlations exist in patients with chronic myelogenous leukemia in blast crisis.30 However, substantial toxicities are associated with the HDara-C regimens31-35 that may be related to the high levels of ara-C or the deamination product ara-U that occur in the blood and CSF during HDara-administration.36-4’ Saturation of the rate of ara-CTP accumulation occurs in human leukemia cells in vitro at exogenous ara-C concentrations in excess of 10 ~mol/L.‘4-‘6 Investigations of the pharmacokinetics of ara-C during HDara-C therapy have consistently demonstrated that plasma ara-C concentrations exceed this value by five- to tenfold.36-42 This suggests that ara-C infusion rates in general clinical use produce plasma ara-C levels that are considerably greater than those required to achieve maximum accumulation of ara-CTP by leukemia cells. The objective of this study was to determine the relationship between plasma ara-C concentrations and the rate of ara-CTP accumulation by leukemia cells during HDara-C therapy. The goal of these investigations was to determine the lowest steady-state concentration of ara-C that would support the maximum accumulation of ara-CTP by leukemia cells.43

Preliminary results of consolidation therapy with high-dose cytosine arabinoside for patients with bad-risk or relapsed acute leukemia or lymphoblastic non-Hodgkin's lymphoma

High-dose Ara-C consolidation therapy for patients with primary refractory or relapsed acute leukemia (AML and ALL) or relapsed lymphoblastic non-Hodgkin's lymphoma (LNHL) was investigated. Between January 1983 and January 1986, 47 adult patients with primary refractory or relapsed AML, ALL or lymphoblastic NHL received a remission induction regimen that included intermediate-dose Ara-C (1g/m22hr q 12hr × 12). Of the twenty-nine (61.7%) patients who achieved complete remission sixteen (AML 9, ALL 5, LNHL 2) received 1–3 consolidation courses that included high-dose Ara-C (3g/m2 q 12hr × 8). Three patients died as a result of major infections during the pancytopenic phase that followed the first consolidation course and 6 relapsed at 4, 4, 6, 8, 9 and 16 months; at the moment of this report the remaining 7 patients have been in continued remission for 8 to 28 months (6 have been in continued complete remission for ⩾ 11 months). The predicted median disease-free interval for patients who survived consolidation therapy is 16 months. Of the 13 patients who did not undergo consolidation chemotherapy 2 subsequently underwent allogeneic bone marrow transplantation and 3 died as a result of major infectious complications while in complete remissiion. Eight patients received no further treatment because they refused or had previously experienced severe toxicity. The median disease-free interval for this group was only 3 months. Our preliminary data on brief intensive consolidation therapy for patients with relapsed or primary refractory leukemia or non-Hodgkin's lymphoma suggest that this kind of treatment prolongs disease-free interval.

Results of high-dose cytarabine therapy. A review

Of the many high-dose Ara-C regimens that have been proposed, the one published by Herzig [24] has been applied most widely. Every 12 h patients receive 3 g/m2 Ara-C for 75-90 minutes for a total of 12 doses. Using that regimen, 25% of patients with refractory acute myelogenous leukemia (AML) and 60% of patients in untreated relapse achieve a complete remission (CR). With few exceptions, complete remissions are obtained after one cycle, median remission duration is between 4 and 6 months. Consolidation or maintenance therapy was not usually given. Currently, numerous modifications of that regimen are under investigation: combinations with other cytostatic agents like anthracyclins, m-AMSA, vincristine; the Capizzi-regimen and intermediate dose Ara-C. Preliminary results of those trials are promising but need to be confirmed by other groups. This survey does not comment on Ara-C toxicity and on Ara-C treatment of CNS leukemia, which are both reviewed in two further articles of this issue.

Experience with intermediate and high dose cytosine arabinoside in refractory acute leukaemia.

28 consecutive patients (age 15-58 years) with refractory acute leukaemia (24 AML, 4 ALL) have been treated with high or intermediate dose cytosine arabinoside (AraC). Twenty patients received AraC at a dose of 3000 mg/m2, twice daily for 6 days (13 patients AraC alone, 7 patients AraC and doxorubicin) and 8 patients received AraC at a dose of 1000 mg/m2, twice daily for 6 days and daunorubicin. 10 of the 20 patients treated with high dose AraC achieved a complete remission (50%) and 2 a partial remission. No patients in the intermediate dose AraC group achieved a remission (p = 0.05). Toxicity of these protocols was acceptable. Vomiting, headache, somnolence, fever, conjunctivitis, and minor cardiac arrhythmias were found most frequently. The pancytopenic period ranged from 16-30 days for the high dose protocol and 14-23 days for the intermediate dose protocol. Sophisticated isolation and blood banking facilities are required in this period. Median duration of remission was 6 months. Results obtained are in favour of the high dose protocol in refractory leukaemia. Only a large dosage increment of AraC can overcome refractoriness of leukaemic blast cells.