2-Chlorodeoxyadenosine with or without daunorubicin in relapsed or refractory acute myeloid leukemia

 2-Chlorodeoxyadenosine (2-CdA) is a purine analogue which has proved to be active in acute myeloid leukemia (AML), especially in children. In adults, results yielded by 2-CdA alone or with ara-C were less encouraging. Here we report on the efficacy of 2-CdA with or without daunorubicin (DNR) in 19 relapsing or refractory adult AML patients, with a median age of 57 years. 2-CdA was administered as a continuous infusion to all patients at a dose of 0.1 mg/kg per day for 7 days. For 14 patients, DNR was added at a dose of 50 mg/m² per day on days 5, 6, and 7. Antileukemic activity was observed in all the patients, but no single complete remission was achieved. One patient had a long-lasting partial response (response rate=5%). The remaining patients died of progressive AML (n=7), uncontrollable infection with persistent disease (n=10), and cerebral hemorrhage (n=1). Median survival from start of 2-CdA therapy was 56 days. Long-lasting neutropenia and transfusion-dependent thrombopenia were encountered in all 16 evaluable patients. Grade 4 hepatic toxicity occurred in one patient. Other side effects included nausea in six, mucositis in three, and mental disturbances in three patients. Compared with 2-CdA alone, the addition of DNR to 2-CdA changed neither the response rate nor the toxicities. In conclusion, our data do not support the use of 2-CdA ± DNR for relapsing or refractory adult AML patients, at least as used in the present regimen. Received: 21 July 1997 / Accepted: 18 November 1997     

Phase II trial of 2-chlorodeoxyadenosine for the treatment of cutaneous T-cell lymphoma [see comments]

We investigated the efficacy of 2-chlorodeoxyadenosine (2-CdA) therapy in patients with mycosis fungoides (MF) and the Sezary syndrome (SS). Between February 1991 and November 1993, 21 patients with relapsed or refractory MF/SS were treated with 2-CdA. 2-CdA was administered by continuous intravenous infusion at a dose of 0.1 mg/kg/d for 7 days initially (13 patients), but was subsequently reduced to 5 days (nine patients) due to hematologic toxicity. All patients had failed to respond to at least one prior treatment for MF/SS (median number of total prior therapies, five; median number of systemic prior therapies, three) and had an Eastern Cooperative Oncology Group performance status of two or better. Cycles were administered at 28-day intervals. Assessable patients received at least 5 days of 2-CdA. Fourteen patients received more than one cycle of 2-CdA. An overall response rate of 28% was achieved. Three patients (14%) had a complete response with a median duration of 4.5 months (range, 2.5 to 16). Three (14%) had a partial response with a median duration of 2 months (range, 2 to 4). Fifteen patients (72%) had no response. The most significant toxicities encountered were bone marrow suppression (62% of patients) and infectious complications (62% of patients). Thirty-eight percent of patients experienced no toxicity from 2-CdA. 2-CdA has activity as a single agent in patients with previously treated relapsed MF/SS. Studies in less heavily pretreated individuals with 2-CdA alone or in combination will be undertaken.     

Treatment of acute myeloid leukemia in elderly patients with oral idarubicin as a single agent

Idarubicin (IDR) is a new anthracycline that can be administered orally. Oral IDR was given at a dose of 30 mg/m2 daily for 3 d in 20 patients aged 65 to 79 yr with previously untreated acute myeloid leukemia (AML). 5 patients whose marrow remained blastic at d 14 received a second course. 8 patients achieved complete remission (6 after one single course). There were: 1 early death, 4 deaths in aplasia, 7 failures. The hematologic toxicity was high. All but 1 patient had to stay in hospital and the duration of neutropenia was 12 to 34 d (median 19). Oral IDR is an effective therapy for AML in elderly patients but the total dose of 90 mg/m2 is too aggressive to be administered safely outside the hospital.     

Fludarabine,cytarabine, and attenuated‐dose idarubicin (m‐FLAI) combination therapy for elderly acute myeloid leukemia patients

We performed a phase II trial to evaluate the efficacy and safety of the modified fludarabine, cytarabine, and attenuated‐dose idarubicin (m‐FLAI) regimen in elderly acute myeloid leukemia (AML) patients. Elderly (≥60 years) AML patients who had not previously received chemotherapy were enrolled in the study. Patients received two consecutive cycles of m‐FLAI chemotherapy as an induction. The m‐FLAI regimen comprised fludarabine (25 mg/m², days 1–4), cytarabine (1,000 mg/m², days 1–4), and attenuated‐dose idarubicin (5 mg/m², days 1–3). The primary end point was complete remission (CR) rate. Secondary end points were overall survival (OS), event‐free survival (EFS), and treatment‐related mortality (TRM). There were 108 patients (median age 68.4 years, M:F = 64:44) enrolled in the study. CR was achieved in 56.5% of patients, and the TRM rate was 21.3%. Median OS and median EFS were 10.2 and 6.6 months, respectively. The mortality at 30 and 60 days was 15 and 21%, respectively. Performance status and comorbidity did not have prognostic value in this patient cohort. Bone marrow expression of CD117 was associated with increased EFS and OS. m‐FLAI is an effective induction regimen for previously untreated AML in elderly patients. In addition, bone‐marrow CD117 expression is an independent favorable prognostic factor in elderly AML patients. (ClinicalTrials.gov number, NCT01247493). Am. J. Hematol. 2013. © 2012 Wiley Periodicals, Inc.     

Cladribine combined with mitoxantrone in the treatment of blastic phase of chronic myeloid leukemia

A phase II clinical study was performed to evaluate the effectiveness and toxicity of cladribine (2-CdA) combined with mitoxantrone (CM regimen) in the treatment of chronic myeloid leukemia in blastic phase (CML BP). A total of 12 adult patients with CML BP were included in this study. 2-CdA was given at a dose 0.12 mg/kg in 2-hour iv infusion on days 1-5 and mitoxantrone 10 mg/m2 i.v. day 1. The cycles were repeated at 4 week intervals in most cases. Complete remission (CR) was defined as the presence of < 5% of blasts in a normo- or hypercellular bone marrow in addition to normal peripheral blood counts and with normal physical examination. A partial response (PR) required normal peripheral blood counts but 5 to 25% marrow blasts. Toxicity was assessed according to WHO criteria. The patients received 21 courses of CM (median 2, range 1-3). Of 12 patients only 2 (17%), achieved PR. Responses were observed in patients with myeloid BP, after 3 and 2 courses, respectively. Myelosuppression was the main toxicity. Four patients (33.3%) had grade 3 or 4 neutropenia and 3 (25%) had grade 3 or 4 thrombocytopenia. Infections occurred in 4 patients (33.3%) and 2 of them died of sepsis shortly after CM treatment. This preliminary results in a small group of patients suggest that CM programme has limited value in pre-treated patients with CML BP. However, this regimen may be used as palliation in the end stage of disease.     

Treatment of relapsed and refractory acute myeloid leukemia with diaziquone and mitoxantrone: a CALGB phase I study

Twenty-one patients with relapsed or refractory acute myeloid leukemia (AML) were treated with mitoxantrone (12 mg/m2/day, days 1-3) and diaziquone (continuous infusion days 1-5). The dosage of diaziquone was increased for sequential cohorts of seven patients from 20 mg/m2/day to 24 mg/m2/day, and finally to 28 mg/m2/day to determine the maximum tolerated dose for this chemotherapy combination. Myelosuppression was the dose-limiting toxicity. The median time to recovery of blood counts was greater at the highest dose of diaziquone (48 days) than at the lower two doses (31 and 28 days). Other toxic effects were minimal. Overall, 9/21 (43%, 95% confidence interval, 0.22 to 0.66) patients achieved complete remission. We conclude that this combination of drugs shows sufficient antileukemic activity with acceptable toxicity to warrant further trials.     

High-dose etoposide and cyclophosphamide without bone marrow transplantation for resistant hematologic malignancy

Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.     

Phase 1 trial of gemtuzumab ozogamicin in combination with enocitabine and daunorubicin for elderly patients with relapsed or refractory acute myeloid leukemia: Japan Adult Leukemia Study Group (JALSG)-GML208 study

We conducted a phase 1 study of a combination of gemtuzumab ozogamicin (GO) plus conventional chemotherapy in elderly patients (??65?years old) with relapsed or refractory CD33-positive acute myeloid leukemia (AML). Patients received a standard dose of enocitabine (200?mg/m2?×?8?days) and daunorubicin (30?mg/m2?×?days 1?C3) plus an escalating dose of GO (1.5?C5?mg/m2 on day 4). The dose escalation of GO was done according to a standard 3?+?3 design following a modified Fibonacci sequence. No dose-limiting toxicities were observed in three patients (median age, 71) at level 1 (1.5?mg/m2) or in three patients (median age, 73) at level 2 (3?mg/m2). Neither veno-occlusive diseases nor sinusoidal obstructive syndromes were noted at either level. However, as GO was withdrawn from the US market in June 2010, based on a randomized study in newly diagnosed AML, we decided not to proceed to the level 3 (5?mg/m2) in order to avoid possibly more severe adverse effects, and also because all six patients experienced grade 4 myelosuppression, with complete remission in three. This study showed that 3?mg/m2 of GO in combination with enocitabine and daunorubicin may be a recommendable dose for a phase 2 study in Japanese elderly patients with CD33-positive AML. The study was registered at the University Hospital Medical Information Network (UMIN) Clinical Trials Registry (http://www.umin.ac.jp/ctr/) as UMIN000002603.     

Treatment of acute myelogenous leukemia in patients over 50 years of age with V-TAD: A southwest oncology group study

Acute myelogenous leukemia (AML) in the elderly continues to have a poor prognosis and new treatment approaches are needed. This Phase II trial was undertaken to evaluate the complete remission rate and toxicity of a chemotherapeutic regimen including etoposide and 6-thioguanine, combined with reduced doses of cytosine arabinoside and daunorubicin (V-TAD) in individuals greater than 50 years of age with AML. Thirty-five patients, ranging in age from 51 to 80 years (median, 66 years), were registered onto the study. Twenty-nine patients were entered at the first dose level (daunomycin 20 mg/m² days 1 and 2, ara-C 75 mg/m² days 1-5, 6-thioguanine 75 mg/m² every 12 hr days 1-5, and etoposide 50 mg/m² days 1, 2, and 3) and six patients underwent therapy at the second dose level (ara-C 75 mg/m² days 1-7 with the remainder of the regimen unchanged). After achieving a complete remission, patients underwent two to three consolidation cycles of chemotherapy. Thirty-one patients were evaluable for response. Thirteen patients (ten of twenty-five at the first dose level and three of six at the second dose level) achieved a complete remission (42%). Median remission duration was 6 months (range 1-21 months). The current regimen, while tolerated, did not result in improved survival compared with prior treatment regimens because of a high incidence of resistant and recurrent leukemia. © 1995 Wiley-Liss, Inc.     

Phase 1 study of low-dose prolonged exposure schedules of the hypomethylating agent 5-aza-2'-deoxycytidine (decitabine) in hematopoietic malignancies

Decitabine (5-aza-2'-deoxycytidine) inhibits DNA methylation and has dual effects on neoplastic cells, including the reactivation of silenced genes and differentiation at low doses and cytotoxicity at high doses. We evaluated, in a phase 1 study, low-dose prolonged exposure schedules of decitabine in relapsed/refractory leukemias. Patient cohorts received decitabine at 5, 10, 15, or 20 mg/m2 intravenously over one hour daily, 5 days a week for 2 consecutive weeks, doses 5- to approximately 30-fold lower than the maximum tolerated dose (MTD). There were 2 groups that also received 15 mg/m2 daily for 15 or 20 days. A total of 50 patients were treated (44 with acute myelogenous leukemia [AML]/myelodysplasia [MDS], 5 with chronic myelogenous leukemia [CML], and 1 with acute lymphocytic leukemia [ALL]), and the drug was well tolerated at all dose levels, with myelosuppression being the major side effect. Responses were seen at all dose levels. However, the dose of 15 mg/m2 for 10 days appeared to induce the most responses (11 of 17 or 65%), with fewer responses seen when the dose was escalated or prolonged (2 of 19 or 11%). There was no correlation between P15 methylation at baseline or after therapy and response to decitabine. We conclude that decitabine is effective in myeloid malignancies, and low doses are as or more effective than higher doses.     

Phase I trial of homoharringtonine in children with refractory leukemia

Continuous infusion of homoharringtonine was administered to 17 children with refractory leukemia. Ten children with acute lymphoblastic leukemia received a total of 18 courses and seven children with acute nonlymphoblastic leukemia had a total of 13 courses. Doses were escalated from 1.65 to 8.5 mg/m2 for 5-10 consecutive days. Side effects included mild nausea and vomiting and transient changes in liver enzymes. Mucositis and diarrhea were more frequently seen at higher dose levels. Grade 3 hypotension and pain were seen at doses of 7 mg/m2 for 10 days. This is considered to be the maximum tolerated dose in this limited phase I trial. None of these previously heavily treated patients achieved a marrow remission.     

Safety and early efficacy assessment of liposomal daunorubicin (DaunoXome) in adults with refractory or relapsed acute myeloblastic leukaemia: a phase I-II study

We have conducted a phase I/II trial to determine the maximum tolerated dose, early safety and efficacy of single-agent liposomal daunorubicin in relapsed or refractory acute myeloid leukaemia (AML). Successive cohorts of six patients received escalated doses of 75, 100, 125 or 150 mg/m2 of DaunoXome for three consecutive days. Responding patients received a further consolidation cycle of DaunoXome at a dose identical to the one inducing complete or partial remission at the various dose levels. Twenty-eight patients with a median age of 50.5 years were enrolled. A maximum tolerated dose was determined at 150 mg/m2. Twelve patients received the second cycle. DaunoXome was well tolerated at all administered levels; dose-limiting toxicities included nausea and vomiting, mucositis and two episodes of cardiotoxicity resulting in the death of two patients. The overall response rate was 46% with a median duration of response of 180 d and a median duration of survival of 208 d. Ten patients demonstrated a complete response following cycle 1, and a further four entered partial response with the first cycle (marrow blasts between 5% and 10%). Of these, three attained complete response with the second cycle (total complete response 13/28). Our results indicate that DaunoXome at a dose of 150 mg/m2 displays acceptable toxicity in a 3-d regimen followed by a 3-d consolidation course at 100 mg/m2/d. At this dose schedule, interestingly high remission rates were achieved, justifying further evaluation of DaunoXome for the treatment of relapsed or refractory AML patients.     

Phase I study of busulfan, cyclophosphamide, and timed sequential escalating doses of cytarabine followed by bone marrow transplantation.

In both animal models and human studies in leukemia, residual disease on day 8 following myelosuppressive therapy is in a proliferative phase and therefore may be sensitive to the S-phase specific drug cytarabine. Based on this concept, 17 patients with refractory or relapsed leukemia or lymphoma undergoing either autologous or allogeneic bone marrow transplantation (BMT) were treated on a Phase I protocol using high doses of busulfan (16 mg/kg, days -10, -9, -8, -7) and cyclophosphamide (120 mg/kg, days -6, -5) followed by escalating doses of a 48-h continuous infusion of cytarabine (starting dose 1000 mg/m2/48 h, days -3, -2). Ten patients received autologous transplants (two with Hodgkin's disease, seven with non-Hodgkin's lymphoma, one with chronic myelogenous leukemia (CML) in blast phase). Seven received allogeneic BMT (two with refractory acute myelocytic leukemia (AML), one with refractory acute lymphoblastic leukemia (ALL) undergoing a second BMT, one with Burkitt's-type leukemia, one with ALL in fifth relapse and two with CML in accelerated/blast phase). Two of these patients received a T cell-depleted haploidentical transplant. The maximum tolerated dose of cytarabine was 1500 mg/m2/48 h; a pulmonary syndrome including dyspnea, hypoxemia, and interstitial infiltrates which responded to aggressive diuresis was the dose limiting toxicity. Of the 10 patients who received cytarabine doses of 2000 or 2500 mg/m2/48 h, five patients developed adult respiratory distress syndrome (ARDS) with three patients requiring intubation; two recovered. Of the nine patients with lymphoma, seven responded with complete tumor clearance (CTC) with two patients tumor-free 13 and 15 months post-BMT, one remained refractory and one died too early to evaluate (TETE).(ABSTRACT TRUNCATED AT 250 WORDS)     

Clofarabine, a novel nucleoside analog, is active in pediatric patients with advanced leukemia

Despite progress in leukemia therapy, most children who experience relapse have a dismal prognosis. New, effective approaches are needed. We conducted a phase 1 study of a novel nucleoside analog, clofarabine, in pediatric patients with refractory and relapsed leukemia. Clofarabine was infused intravenously over 1 hour each day for 5 days. Six dose levels, between 11.25 and 70 mg/m(2) per day for 5 days, were studied in 25 patients. A modified 3 + 3 phase 1 design was followed with 30% dose escalation until the dose-limiting toxicity (DLT) was defined. The maximum tolerated dose (MTD) was 52 mg/m(2) per day for 5 days. At the end of infusion at MTD, clofarabine triphosphate levels in leukemia blasts varied between 6 microM and 19 microM, which resulted in complete and sustained inhibition of DNA synthesis. The DLT was reversible hepatotoxicity and skin rash at 70 mg/m(2) per day for 5 days. Twenty-five patients were treated. Five patients achieved complete remission (CR), and 3 achieved partial remission (PR), for an overall response rate of 32%. Clofarabine is well tolerated and shows significant antileukemic activity in heavily pretreated children. Multicenter phase 2 trials in pediatric acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) are ongoing.     

Fludarabine as a risk factor for poor stem cell harvest, treatment-related MDS and AML in follicular lymphoma patients after autologous hematopoietic cell transplantation

Fludarabine is an effective treatment for follicular lymphoma (FL), but exposure to it negatively impacts stem cell mobilization and may increase the risk of subsequent myelodysplastic syndrome and acute myelogenous leukemia (t-MDS/AML). We hypothesized that the risk that fludarabine imparts to stem cell mobilization and t-MDS/AML would be affected by dose or timing. All patients with FL treated at Cleveland Clinic from 1991 to 2007 with autologous hematopoietic cell transplantation were evaluated. Recursive partitioning analysis was used to explore associations of fludarabine and mitoxantrone dose and timing with poor stem cell harvest and t-MDS/AML. We identified 171 patients, of whom 52 previously received fludarabine. Patients exposed to fludarabine prior to auto-HCT were more likely to require >5 days of leukapheresis (P<0.001) and second stem cell mobilization (P<0.001), especially at a cumulative dose >150 mg/m(2). Univariable risk factors for t-MDS/AML included the number of chemotherapy regimens before auto-HCT, the need for >5 days of leukapheresis to collect CD34+ cells and fludarabine exposure in a dose-dependent manner, particularly when >500 mg/m(2). A cumulative dose of fludarabine >150 mg/m(2) increases the risk for poor stem cell harvests and any exposure increases the risk of t-MDS/AML, with the greatest risk being at doses >500 mg/m(2).     

A randomized trial of conventional dose vs reduced dose in BHAC-DM therapy for acute myelogenous leukemia in elderly patients

Twenty-nine patients aged 60-75 years with newly diagnosed acute myelogenous leukemia (AML) were randomized to receive BHAC-DM either at a reduced dose (S-1 group, n = 13; BHAC 150 mg/m2 1-7 day, DNR 30 mg/m2 1-3 day, 6MP 70 mg/m2 1-7 day) or the conventional dose (S-2 group, n = 16; BHAC 200 mg/m2 1-7 day, DNR 40 mg/m2 1-3 day, 6MP 70 mg/m2 1-7 day). On day 7, patients were given therapy for 2 more days if the ratio of blasts in their bone marrow was more than 15%. Granulocyte-colony stimulating factor was injected when the leukocyte count decreased below 1,000/microliter. The rates of complete remission were 46.2% in the S-1 group and 43.8% in the S-2 group. No significant differences in response distinguished the 2 groups. The mortality rate during myelosuppression was 1/13 in the S-1 group and 1/16 in the S-2 group. The rate of treatment-related death was 10.1% for all patients. Grade-4 adverse effects were not seen in any of the patients. We concluded that the conventional dose of BHAC-DM was as acceptable as the reduced dose in elderly patients with AML.     

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.     

Intermediate and high-dose ARA-C and m-AMSA (or daunorubicin) as remission and consolidation treatment for patients with relapsed acute leukaemia and lymphoblastic non-Hodgkin lymphoma

27 patients (aged 15-55 years) with relapsed acute myelogenous (AML) and lymphoblastic leukaemia (ALL), and with lymphoblastic non Hodgkin's lymphoma (NHL) have been treated with intermediate dose cytosine arabinoside (AraC, 1 g/m2 q 12 h X 12) and 3 d of m-AMSA (20 patients), 90-115 mg/m2 daily, or daunorubicin (7 patients). 18 of them attained a complete remission (AML 10/14, ALL 3/5, NHL 5/8). 7 patients received consolidation treatment with 1-2 courses comprising 4 d of AraC (3 g/m2 q 12 h X 8) and m-AMSA (90-115 mg/m2) on d 5 of each course. 2 patients underwent allogeneic bone marrow transplantation and 9 received no further treatment after remission induction. In addition to vomiting, fever and conjunctivitis, toxicity in 6 patients included a combination of severe diarrhoea, fever and signs of paralytic ileus. 3 of them died during the pancytopenic phase. The pancytopenic period ranged from 16-25 d (median 21 d) after the remission induction and 14-21 d (median 19 d) after the consolidation course. Median remission duration was 5 months for those patients who received no treatment after remission induction and greater than 9 months (4+ - 16+ months) for the patients who received consolidation courses. Increased dosages of AraC are active in relapsed leukaemia and lymphoma, although optimal dose and schedule are still undetermined.     

2-Chlorodeoxyadenosine (cladribine) in the treatment of hairy cell leukemia and hairy cell leukemia variant: 7-year experience in Poland

Abstract: Between January 1991 and December 1997, 103 patients, 97 with typical hairy cell leukemia (HCL) and 6 with HCL-variant (HCL-V) were treated with 2-chlorodeoxyadenosine (2-CdA) given as 2-h infusion for 5 consecutive d at a daily dose 0.12 mg/kg. To our knowledge this is the largest cohort of HCL patients treated with this type of regimen. Median follow-up amounted to 36 months. Fifty-six of 97 patients with typical HCL were newly diagnosed and 41 were relapsed after previous treatment. Splenectomy as a first-line therapy was performed in 23 patients and 18 remaining patients received prednisone, chlorambucil or interferon-α (IFN-α) alone or in combinations. Seventy-five (77.3%) patients entered CR and 18 (18.6%) achieved PR, giving an overall response rate of 95.9%. The mean time of first CR duration amounting to 32 months (range 3–72) did not correlate to the number of 2-CdA cycles. 2-CdA was equally effective in treatment of newly diagnosed patients and patients who relapsed after previous therapeutic procedures. Relapse of the disease occurred in 20 of 75 patients who achieved CR after 2-CdA and was usually manifested by very discrete changes in peripheral blood counts (neutropenia and/or relative lymphocytosis). The mean progression-free survival (PFS) time in this group was 37.4 (range 10–66) months. Ten of 20 relapsed patients were retreated with 2-CdA given an identical course to the first one. Seven patients entered second CR lasting 19+ (range 8–47) months and 3 experienced PR. This confirms the previous observations that 2-CdA gives no resistance to leukemic clone. Ten remaining patients have not required retreatment so far and remain in a good clinical and hematological state. The results of HCL-V treatment with 2-CdA were poor. Only 2 patients achieved PR and 4 patients did not respond to this drug. Seven patients (5 with typical HCL and 2 with HCL-V) died, 3 of causes unrelated to the disease. Second neoplasms were noted in 5 patients. 2-CdA-related side effects resulted mainly from myelosuppression and infectious complications. In conclusion we confirm the effectiveness of 2-CdA in inducing CR in patients with typical HCL, but this drug is unable to completely eradicate the leukemic clone which results in the relapse of the disease. The real incidence of the relapse rate may be underestimated unless bone marrow biopsy is performed. The results of our study indicate that a 2-h infusion of 2-CdA in HCL patients is at least as effective as a 24-h infusion but more convenient to the patients, and may be given on an outpatient basis.     

High-dose cytosine arabinoside and mitoxantrone: a highly effective regimen in refractory acute myeloid leukemia

In a clinical phase I/II study, high-dose cytosine arabinoside and mitoxantrone (HAM) were given in combination to 40 patients with refractory acute myeloid leukemia. All patients had received a 9-day combination of thioguanine, Ara-C, and daunorubicin (TAD-9) as standardized first-line treatment. Refractoriness was defined as (a) nonresponse against two TAD-9 induction cycles, (b) early relapse within the first 6 months on monthly maintenance or after TAD-9 consolidation, (c) relapse after 6 months with nonresponse against one additional TAD-9 cycle, and (d) second and subsequent relapses after successful TAD-9 therapy at the preceding relapse. Therapy consisted of HD-Ara-C 3 g/m2 every 12 hours on days 1 through 4; mitoxantrone was started at 12 mg/m2/day on days 3, 4, and 5 and was escalated to 4 and 5 doses of 10 mg/m2/day on days 2 through 5 and 2 through 6. Of the 40 patients, 21 achieved a complete remission (53%), 1 patient had a partial remission, and 5 patients were nonresponders. Thirteen patients died in aplasia due to infections (n = 11), pericardiac effusion, or acute cardiomyopathy. Nonhematologic side effects consisted predominantly of nausea and vomiting, mucositis, and diarrhea. Central nervous system (CNS) symptoms were observed during six treatment courses. Recovery of blood counts occurred at a median of 27 days from the onset of treatment; the median time to complete remission was 36 days. Two of the 21 responders underwent successful bone marrow transplantations. The median remission duration for the remaining 19 patients is 4.5 months, and the median survival time is 9 months. These data emphasize that HAM has high antileukemic activity in refractory AML and strongly suggest starting the combination at earlier stages in AML therapy.