Busulfan pharmacokinetics do not predict relapse in acute myeloid leukemia

The purpose of this study was to evaluate the influence of busulfan (BU) pharmacokinetics on survival, grades II-IV acute graft-versus-host disease (GVHD), non-relapse mortality (NRM) and relapse in a group composed of 45 children (<18 years) and seven adults with acute myeloid leukemia (AML) in first complete remission and undergoing hematopoietic stem cell transplantation (SCT). Fifty-two patients underwent autologous (n = 25) or allogeneic (n = 27) SCT. The median age was 8.9 years (range 0.6-53 years). Conditioning therapy consisted of BU and cyclophosphamide. Improved disease-free survival was found in those patients with a steady-state concentration of BU (CssBU) below the median (<578 mg/ml, P = 0.05), and the same trend was noted for overall survival (P = 0.07). This was secondary to a higher incidence of NRM in the group of patients with CssBU above the median (P = 0.06). There was no significant correlation with CssBU and relapse (P = 0.31). No association between CssBU and GVHD was found in allogeneic patients (P = 0.30). Relapse was evaluated among the subgroups of age (< or >10 years) and transplant type (allogeneic or autologous) with no statistically significant association observed among these factors. Multiple regression analysis for relapse revealed no significant correlation with CssBU above or below the median, age, or transplant type. In this study, CssBU below the median did not correlate with an inferior outcome for patients with AML. Pharmacokinetic dosing of BU may be important for prevention of NRM but does not appear to influence the risk of relapse in this largely pediatric population with AML.     

Busulfan/etoposide--initial experience with a new preparatory regimen for autologous bone marrow transplantation in patients with acute nonlymphoblastic leukemia

Current intensive chemotherapy for acute nonlymphoblastic leukemia (ANLL) results in a complete remission in the majority of patients. Unfortunately, the duration of remission is short and most of the patients will experience a relapse of their underlying disease. Autologous bone marrow (BM) transplantation is being explored as a treatment modality designed to improve relapse-free survival. We have conducted a phase II trial exploring the combination of busulfan (16 mg/kg) and etoposide (60 mg/kg) in an attempt to improve antitumor efficacy using this novel preparative regimen. To date, 50 patients (48 with ANLL and 2 patients with biphenotypic acute leukemia) have been treated. The first 20 patients received unmanipulated BM; 28 patients subsequently received 4-hydroperoxycyclophosphamide (4-HC) (60 micrograms/mL)-purged bone marrow, and 2 patients with biphenotypic acute leukemia received both 4-HC (60 micrograms/mL) and etoposide (5 micrograms/mL)-purged BM. Thirty-four patients were in first complete remission (CR1), 12 patients in second complete remission (CR2), and 4 patients in relapse. The median time from first complete remission to BM harvest was 3 months (range, 0.8 to 4) compared with median time of 2 months (range, 1.5 to 5.0) for patients in second complete remission. The median time from harvest to transplant was 1 month for both groups (range, 0.4 to 36). A median of 0.7 x 10(8) (range, 0.2 to 1.4) mononuclear cells were infused. Patients achieved an absolute neutrophil count of > or = 500/microL at a median of 26 days (range, 13 to 96), an untransfused platelet count > or = 20,000/microL at a median of 56 days (range, 15 to 278) and a sustained hematocrit > or = 30% at a median of 50 days (range, 19 to 116). Twenty-six patients are alive and in continued CR. Follow-up of the surviving patients ranged from 6 months to 66 months with a median follow-up of 31 months. Patients receiving purged BM have an actuarial disease-free survival of 57% with a relapse rate of 28% compared with patients receiving unpurged BM whose actuarial disease-free survival is 32% with a relapse rate of 62% (P = .06 for relapse rate). The most significant extramedullary toxicities for this regimen are hepatic and cutaneous (including mucositis). The BU/VP-16 regimen is associated with a significant proportion of patients surviving disease free, especially in the group receiving purged BM. Whether this regimen offers a substantial improvement in disease-free survival over currently used regimens will require a prospective randomized study.     

Busulfan, cyclophosphamide, and etoposide as high-dose conditioning regimen in patients with malignant lymphoma

We investigated the efficacy and toxicity of the combination of busulfan, cyclophosphamide, and etoposide (Bu/Cy/VP-16) as a preparative regimen prior to autologous hematopoietic stem cell transplantation (ASCT) in patients with Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL). Fifty-three patients with recurrent ( n=30), refractory ( n=20), or high-risk ( n=3) lymphoma were enrolled. The 10 patients with HD and 43 with NHL (median age: 46 years, range: 18-64) received busulfan (16 mg/kg), cyclophosphamide (120 mg/kg), and etoposide (30 or 45 mg/kg) followed by ASCT. A total of 50 patients (94%) were consolidated in complete ( n=25) or partial ( n=25) remission, whereas 3 patients had chemoresistant disease before Bu/Cy/VP-16. Thirty-five patients (66%) had received prior radiotherapy (RT) excluding total body irradiation (TBI) as part of the conditioning regimen. The main nonhematological toxicities (grade II-IV according to the Bearman score) in 52 evaluable patients were mucositis (79%) and hepatic toxicity (15%). Severe veno-occlusive disease (VOD) occurred in three patients (5.8%) including one treatment-related death caused by VOD. Overall, treatment-related mortality was 3.8%. After a median follow-up for surviving patients of 21 months (range: 6-118), 20 patients (38%) are in continuous complete remission, 8 patients (15%) are alive in relapse, and 25 patients (47%) died. Probabilities of relapse, event-free survival, and overall survival at 3 years were 63% [95% confidence interval (CI): 48-79%], 31% (95% CI: 17-46%), and 43% (95% CI: 27-59%), respectively. In conclusion, Bu/Cy/VP-16 is an effective and well-tolerated conditioning regimen in patients with HD and NHL. Both toxicity and outcome were not significantly different in patients treated with 30 mg/kg and 45 mg/kg etoposide, respectively. The observed long-term results are even comparable to those published for other established high-dose protocols, including TBI-based regimens. However, further investigations are necessary to evaluate the value of Bu/Cy/VP-16 as a high-dose protocol for malignant lymphoma, especially in patients who have already received extensive RT.     

Low-dose cimetidine in the acute treatment of duodenal ulcer. Comparison of a single nocturnal dose regimen with a twice daily regimen

A 0.5 g daily dose of cimetidine was as effective as a 1 g dose in the acute treatment of duodenal ulcer patients in Hong Kong. The aims of the present study were, first, to determine whether low-dose cimetidine treatment was as effective as standard doses in acute duodenal ulcer treatment of patients in Singapore, and second, to compare a single nocturnal dosage regimen with a twice daily regimen. In this single centre, double-blind, controlled trial, 282 patients with endoscopically proven duodenal ulcer were randomized to receive four weeks' treatment with cimetidine using one of three dosage regimens: (A) 800 mg at night; (B) 400 mg at night; or (C) 400 mg twice daily. Two hundred and forty-seven patients were evaluated. The incidences of healing at four weeks were: (A) 40/80 (50%), (B) 39/88 (44%); and (C) 48/79 (61%); (B vs C: P less than 0.05; A vs C: NS; 95% confidence limits: -5% to 27%; A vs B: NS, 95% confidence limits: -6% to 21%). Of 183 patients who had antral biopsies taken, 176 (96%) had histological gastritis, while 167 (91%) were positive for Helicobacter-like organisms. The occurrence of gastritis or Helicobacter-like organisms had no influence on ulcer healing. A 400 mg dose of cimetidine is therefore suboptimal for the treatment of duodenal ulcer in patients in Singapore. A single nocturnal dosage regimen may be less effective than a twice daily regimen.     

High remission rate in acute myeloblastic leukemia in children treated with high-dose methylprednisolone.

Since the differentiating effect of high-dose methylprednisolone (HDMP) on myeloid leukemic cells has been shown in one of our patients with acute myeloblastic leukemia (AML-M4), 27 previously untreated children with AML were given HDMP (20-30 mg/kg per day) combined with cytosine arabinoside (Ara-C; 3 mg/kg) for the first 2 weeks of induction therapy. Marked clinical improvement was observed in all patients with the exception of one who died within 24 hours of the treatment. Enlarged liver and spleen (greater than 5 cm) became nonpalpable in 3 (37%) out of 8 and 5 (100%) out of 5 patients, respectively, and bone marrow blasts decreased below 5% in 7 patients (27%) within 2 wk of HDMP and Ara-C treatment. Adriamycin (1 mg/kg) was added 2 wk after initiation of induction therapy. Twenty-two (84.6%) of the 26 patients achieved complete remission, 3 (11.5%) had partial remission and no response was obtained in one. Treatment was well tolerated. The addition of HDMP as a differentiating and/or cytolytic agent to conventional anti-leukemic chemotherapy increased the complete remission rate and prolonged the duration of remission of our AML patients.     

Amikacin once daily: a new dosing regimen based on drug pharmacokinetics

Once-daily dosing of amikacin is a novel therapy regimen which seems pharmacokinetically appropriate for the primary group of patients considered for aminoglycoside therapy. In this study of 29 elderly patients with serious infections, amikacin 11 mg/kg or 15 mg/kg bw was administered as a short-term (30 min) intravenous infusion. The amikacin serum concentration-time profile was best described by a bi-exponential equation with a half-life of about 4.8 h. A triexponential equation was not applicable because the slow terminal elimination phase was not detected during the 24 h dosing interval. In practice, a uni-exponential equation is often used, and this may lead to incorrect conclusions about the elimination rate of amikacin. Amikacin clearance provides more direct information about elimination of amikacin than does serum half-life. Thus, there was a better correlation between the individual amikacin clearances and creatinine clearances (r = 0.89), than between the serum half-lives of amikacin and the creatinine clearances (r = 0.71). For elderly patients a smaller dose of amikacin than the regular daily dose of 15 mg/kg bw, i.e. about 11 mg/kg bw, seems recommendable, when it is given once daily. From the data obtained it is also obvious that once-daily dosing of amikacin does not eliminate the need for checking serum concentrations of the drug.     

Amsacrine combined with etoposide and high-dose methylprednisolone as salvage therapy in acute lymphoblastic leukemia in children

In a retrospective analysis of 24 children with refractory or multiply relapsed acute lymphoblastic leukemia (ALL), a salvage regimen comprising amsacrine, etoposide, and high-dose methylprednisolone AEP achieved a significant treatment response in 11 of 19 evaluable patients (8 complete and 3 partial remissions). Five of 9 AEP-responsive patients who underwent subsequent stem cell transplantation are alive (median follow-up: 43 months; range 10 to 91). The load of minimal residual disease prior to transplantation appears to be predictive for outcome in this very poor-prognosis subgroup of ALL.     

Myeloprotective effect of short-course high-dose methylprednisolone treatment before consolidation therapy in children with acute myeloblastic leukemia

In our previous studies, short-course high-dose methylprednisolone (HDMP) has been shown to shorten the chemotherapy-induced neutropenic period by stimulating the CD34(+) hematopoietic progenitor cells in children with acute leukemia. In this study, we investigate the role of short-course HDMP on induction of a myeloprotective effect when administered before consolidation therapy consisting of high-dose cytosine arabinoside and daunorubicin. Thirty-four consecutive newly diagnosed children with acute myeloblastic leukemia (AML) who received 64 courses of consolidation regimen were entered into the study. The patients received HDMP (group A) at a daily dose of 30 mg/kg methylprednisolone starting 4 days before the initiation of consolidation therapy. The control group did not receive HDMP (group B). There were no differences in the white blood cell (WBC) and absolute neutrophil counts (ANC) between group A (at day -4) and group B (at day 0) at the beginning of the study (medians: 3 x 10(9)/L vs. 3.2 x 10(9)/L and 1.5 x 10(9)/L vs. 1.7 x 10(9)/L, respectively). The WBC count increased significantly from 3 x 10(9)/L to 6.4 x 10(9)/L, and ANC increased from 1.5 x 10(9)/L to 3.9 x 10(9)/L after 4 days of HDMP treatment in group A (P < 0.01). Following high-dose chemotherapy, the median values of WBC and ANC also remained higher than the control values during the 16 days of the follow-up period. The neutropenic period was significantly shorter in the HDMP group than in the control group (9 +/- 5.2 days vs. 22 +/- 4.7 days) (P < 0.05). The duration of hospitalization and the interval between two chemotherapy cycles were significantly decreased in group A when compared group B (9 +/- 2.7 vs. 14 +/- 2.7 days; 22 +/- 4.7 vs. 26 +/- 4.2 days, respectively) (P < 0.05). Moreover, following consolidation therapy, the number of patients with ANC values below 0.5 x 10(9)/L was lower in group A when compared the group B. In conclusion, the administration of short-course (4 days) HDMP before high-dose chemotherapy has been found to be beneficial for reducing the duration and severity of neutropenia. Further studies with short-course HDMP are required to evaluate its myeloprotective effects in patients with other malignancies.     

Vincristine pharmacokinetics is related to clinical outcome in children with standard risk acute lymphoblastic leukemia

Vincristine is a key drug in the treatment of childhood and adult acute lymphoblastic leukemia (ALL), and many other childhood malignancies. Despite decades of wide clinical use, no data on the correlation between vincristine pharmacokinetics and long-term clinical outcome have been published. We here report clinical data (median follow-up time 10·5 years, range 7·3–12 years) for 86 children with B-cell precursor ALL, in whom vincristine kinetics were studied on treatment day 1. The median total plasma clearance was 429 and 331 ml/min per m² and the area under the plasma concentration-time curve (AUC) was 4·49 and 5·40 mg/l × min in relapse and non-relapse patients, respectively (not significant). In standard risk patients, where treatment depends more heavily on vincristine than in other subgroups, the relative risk (RR) of relapse was significantly increased for patients with clearance values above median (RR 5·2; P  = 0·036), or AUC values below median (RR 5·8; P  = 0·025). Our data suggest a relationship between the antileukemic effect and the systemic exposure of the drug, which warrants further studies.     

Treatment of acute leukemia with amsacrine and high-dose cytarabine

We varied the number of doses of high-dose cytarabine (3 g/m2) given to patients with acute leukemia in relapse who were receiving therapeutic doses of amsacrine (600 mg/m2/course). Twelve patients received 13 courses of therapy. Two of six patients with acute nonlymphocytic leukemia and one of three with acute lymphoblastic leukemia achieved remission. Dose-limiting toxicity (diarrhea) was seen in patients receiving more than five daily doses of high-dose cytarabine. We conclude that therapeutic doses of amsacrine can be combined safely with five daily doses of high-dose cytarabine and that a formal study is now required to assess the efficacy of this regimen.     

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.     

Comparison of toxicity and outcome in patients with acute myeloid leukemia treated with high-dose cytosine arabinoside consolidation after induction with a regimen containing idarubicin or daunorubicin

 The toxicity and outcome after high-dose ara-C/daunorubicin (HDara-C/DNR) consolidation therapy in de novo AML was compared in 11 patients who received an idarubicin-containing induction therapy (IDA; from June 1995 to March 1997) and 16 patients pretreated with daunorubicin (DNR; from July 1990 to May 1995) for induction. The DNR group consisted of two cohorts, one (n=6) of patients who had received, as had the IDA group, two induction and one intermediate-dose ara-C consolidation courses, and another (n=10) of patients who had been pretreated with one induction and one consolidation course prior to HDara-C/DNR. There was no difference in the relative dose between the three cohorts. Following HDara-C/DNR, the IDA-pretreated patients experienced a more prolonged myelosuppression during consolidation therapy compared with the DNR group. Duration of neutropenia (<500 neutrophils/μl) following HDara-C/DNR was 31.2 ± 16 days (mean ±SEM) in the IDA group compared with 18.7 ± 5 days in the DNR group (p<.001 Mann-Whitney U-test). The duration of thrombocytopenia (platelets <25 000/μl) was 34.8 ± 20 days in the IDA group vs. 18.5 ± 6 days in the DNR group (p<.005). The more prolonged myelosupression was associated with a longer duration of fever (18.9 ± 24 vs. 6.9 ± 5.2 days). A greater incidence, length (11 ± 8 vs. 1.2 ± 2 days), and severity of diarrhea were observed in the IDA-pretreated group. Three of 11 IDA patients experienced WHO grade III-IV diarrhea. In the IDA group two patients developed severe enterocolitis with Candida septicemia, and one of these patients died. One patient in the IDA group died during prolonged aplasia. In the DNR group 6/16 patients experienced grade I-II diarrhea. Two patients in each group died during consolidation therapy. The CR rate was 87% in the IDA group and 79% in the DNR group. Relapse-free survival after HDara-C is 50% at a median follow-up of 60 months in the DNR group and 45% after a median follow-up of 17 months in the IDA group. Whether the advantage of the superior response rate in the IDA-treated patients may be lost during HDara-C consolidation treatment due to increased toxicity remains to be proven in larger trials. Received: 27 October 1997 / Accepted: 28 January 1998     

Treatment of adult acute lymphoblastic leukemia with Ad-VP-L regimen

From 1985 to 1989, we treated a total of 24 adult patients with acute lymphoblastic leukemia, 17 males and 7 females, median age 26 (range 16-70 yr), with a protocol consisting of remission induction with Adriamycin (ADR), vincristine (VCR), prednisolone (PDN) and 1-asparaginase (ASP), followed by two consolidation courses with ADR, VCR, cyclophosphamide, methotrexate and PDN (Ad-VEMP), combined with CNS-prophylaxis (intrathecal MTX and PDN). Cyclic chemotherapy with VMM (vindesine, 6-MP and MTX) and Ad-VEMP regimen or therapy with VMM regimen only was used to maintain remission. Twenty patients (83.3%) achieved complete remission. The median durations of overall survival and complete remission were 20 and 18 months respectively. The significant unfavorable prognostic factors associated with survival were old age (more than 50 yr), high WBC counts on admission (more than 20,000/microliters) and low nadir of WBC counts (less than 500/microliters). The responders who received ASP for a period of 10 days had longer survival durations than did other responders. Remission did not continue long enough with our protocol, although a high CR rate was achieved. We conclude that the design of consolidation and maintenance therapy must be improved in order to obtain a longer duration with our protocol.     

Cord blood transplantation for acute myelogenous leukemia using a conditioning regimen consisting of granulocyte colony-stimulating factor-combined high-dose cytarabine, fludarabine, and total body irradiation

The cytotoxic effect of cytarabine (Ara-C) on myeloid leukemic cells is enhanced by concomitant use of granulocyte colony-stimulating factor (G-CSF) in vitro. The feasibility of a conditioning regimen consisting of G-CSF-combined 24 g/m2 Ara-C, 90 mg/m2 fludarabine, and 12 Gy total body irradiation was studied for five patients with acute myelogenous leukemia in cord blood transplantation (CBT). Graft vs. host disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate. After the conditioning regimen, 2.48 x 10(7)/kg (2.28-3.53) of cord blood nucleated cells was infused. Neutrophil counts consistently >0.5 x 10(9)/L was achieved 24 d (22-32) after CBT. Grade I stomatitis and gastrointestinal toxicities occurred in all patients. Grades I and II acute GVHD occurred in one and four patients, respectively, which resolved without steroid therapy. Sepsis and aspergillosis occurred in two and one patients, respectively. All patients were alive without leukemia relapse at a follow up of 15 months (12-43) after CBT. This conditioning regimen could avoid the toxicities of high-dose cyclophosphamide but might enhance the cytotoxic effect of Ara-C. Large-scale studies will be needed to determine the efficacy and safety of the conditioning regimen in CBT.     

Peripheral blood stem cell collection in children with acute leukemia: effectiveness of the 'DIAVE' mobilizing regimen

Few experiences of peripheral blood (PB) hematopoietic stem cell mobilization for autologous transplantation have been reported to date in children with acute leukemia (AL). The five-drug-chemotherapy 'DIAVE' (dexamethazone, idarubicine, cytosine-arabinoside, vincristine, etoposide), followed by G-CSF, previously reported as consolidation, was adopted as a mobilization regimen in 29 children (median age: 8 years, range: 3-21; median weight: 34 kg, range: 15-73) with ALL in second remission (CR2: 21), in CR3 (2) or ANLL in CR1 (6). A median peak of 94 x 10(6) CD34(+)cells/l (range: 10-604) was reached at a median time of 12 days (range: 10-18) after the beginning of the mobilizing regimen, which was well tolerated. A median of 10.9 x 10(6) CD34(+)cells/kg (range: 2.4-56.6) were collected in 25 patients (86%), approaching 40 x 10(6)/l CD34(+) cells in the PB (ALL in CR2: 20/21, in CR3: 0/2; ANLL: 5/6) by means of one (20) or two (5) leukaphereses; a median of 2.5 blood volumes was processed. Patients with ANLL mobilized more cells than patients with ALL; moreover, the shorter the interval between remission and mobilizing therapy, the higher was the yield. The products collected underwent purification, aiming at achieving complete removal of possibly contaminating leukemic cells, in 21 cases; also, unmanipulated aliquots were stored as rescues for all but one patient. All the 23 patients undergoing transplantation engrafted (ANC >0.5 x 10(9)/l) at a median of 12 days. In conclusion, the DIAVE regimen compares favorably with conventional mobilizing regimens, usually containing cyclophosphamide, in terms of low toxicity, collection time predictability, and efficacy, as shown by the high proportion of patients mobilizing, the large amounts of stem cell collected by means of one or two leukaphereses only, and the prompt engraftment after infusion.     

Busulfan disposition in children

Children receive busulfan orally as part of myeloablative therapy before bone marrow transplantation for malignant and nonmalignant conditions. Children have been reported to have a low incidence of severe toxicity and significant rates of failure to achieve full engraftment. We evaluated the disposition of busulfan in children between 2 months and 3.6 years of age with lysosomal storage diseases, leukemia, and immunodeficiency disorders receiving oral doses of 1 or 2 mg/kg using a gas chromatographic assay. Peak concentrations were lower than those previously reported for adults, ranging from 1.4 to 5.2 mumol/L. The harmonic mean of the elimination half-life was 92 minutes, which is only slightly faster than that for adults (140 minutes). However, the area under the curve ranged from 400 to 1,000 (715 +/- 240) mumol.min/L, substantially lower than in adults receiving 1 mg/kg (range, 710 to 5,100 mumol.min/L; mean +/- SD, 2,180 +/- 1,200). The apparent volume of distribution (assuming complete bioavailability) ranged from 0.28 to 3.53 L/kg (1.42 +/- 0.86), which is more than twice that reported for adults (0.60 +/- 0.42). Busulfan clearance rate normalized to surface area is twice as high in children (200 +/- 100 mL/min/m2) as it is in adults (95 +/- 54 mL/min/m2). Alterations in bioavailability (absorption or first pass elimination) or in actual volume of distribution may account for these differences in drug disposition. The observed differences suggest the need for separate phase I dose escalation studies in children with accompanying pharmacokinetic assessment.