Clinical evaluation of recombinant human G-CSF in children with cancer]

Recombinant human granulocyte colony-stimulating factor (rG-CSF), produced by Chinese hamster ovary cells, was administered in 69 chemotherapy-induced neutropenic pediatric patients (pts) with malignant tumors. Each pt received two cycles of the same chemotherapy and had neutropenia with absolute neutrophil counts (ANC) less than 500/microliter in the first cycle. Initiating 72 hours after termination of chemotherapy in the second cycle, rG-CSF (2 micrograms/kg/day) was given subcutaneously or intravenously to each pt for 10 days. rG-CSF significantly increased ANC at nadir; 72 +/- 14 vs. 206 +/- 40/microliter (data in the first cycle vs. data in the second cycle, respectively), and reduced the period of neutropenia with ANC less than 500/microliter; 9.7 +/- 0.6 vs. 5.1 +/- 0.6 days, and the period for restoration to ANC greater than or equal to 1,000/microliter after initiation of chemotherapy; 25.5 +/- 0.6 vs 17.5 +/- 0.9 days. rG-CSF did not affect other components of peripheral blood. The number of days with fever greater than or equal to 38 degrees C was significantly reduced by rG-CSF treatment. Neck pain and lumbago were observed in one pt, pollakisuria in one pt, and elevation of the serum levels of LDH and uric acid in one pt, however these were mild to moderate, transient, and resolved without any specific treatment. We concluded that rG-CSF was effective in neutropenia induced by intensive chemotherapy for malignant tumors without any serious side effects.     

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.     

Blood neutrophil increment after a single injection of rhG-CSF or rhGM-CSF correlates with marrow cellularity and may predict the grade of neutropenia after chemotherapy

Summary. The grade of neutropenia after chemotherapy seems to be correlated to the bone marrow cellularity as judged by biopsies. Prolonged blood neutropenia after sequential chemotherapy reduces dose intensity and increases the risk of severe infections. A predictive non-invasive test for marrow cellularity is needed in the attempt to predict chemotherapy-induced blood neutropenia.
Thirty-one patients with haematological disorders were studied with measurements of blood absolute neutrophil counts (ANC) 24 h after a single subcutaneous injection of recombinant human granulocyte colony stimulating factor (rhG-CSF) or granulocyte-macrophage CSF (rhGM-CSF). Before cytokine administration all patients had bone marrow biopsies performed.
The median increase in blood ANC 24 h after cytokine administration was 15·9 × 10⁹/l (range 3·7–34·2) in 18 patients with normo- or hypercellular marrows and only 0·4 × 10⁹/l (range 0·0–11·2) in 13 patients with hypocellular marrows ( P <0·00001). An increase in ANC or more than 5 × 10⁹/l was predictive for normo- or hypercellular bone marrows with a sensitivity and specificity of 94% and 84%, respectively.
A subsequent pilot study in selected patients with prolonged neutropenia was performed. The ANC increment in 12 cases before chemotherapy correlated to the grade of neutropenia and may predict the risk of febrile neutropenia.
It is suggested that blood responsiveness to myeloid growth factors correlates with marrow cellularity and may identify outpatients with risk for severe neutropenia after cyclic chemotherapy.     

In vitro and in vivo activity of human recombinant granulocyte-macrophage colony-stimulating factor in dogs

Although it is well documented that human granulocyte-macrophage colony-stimulating factor (GM-CSF) controls the production and functional activity of human and nonhuman primate granulocytes and macrophages, relatively little is known about its effects on cells obtained from other species. The molecular cloning of the complementary DNA for human GM-CSF has made it possible to determine the cross-reactivity of the purified recombinant human material (rhGM-CSF) on cells of other species. The results presented herein show that specific receptors for human GM-CSF exist on dog bone marrow cells and mature circulating dog granulocytes. The number of the receptors and the apparent binding affinity of the rhGM-CSF to its receptors on granulocytes were similar to those observed either on human or monkey cells. In cultures of dog bone marrow cells, rhGM-CSF was capable of promoting colony formation in a dose-dependent manner. Human GM-CSF also primed dog granulocytes for increased production of reactive oxygen metabolites in response to either phorbolmyristic acetate-or zymosan-activated dog serum. In vivo, s.c. administration to healthy dogs of rhGM-CSF in daily doses of 15, 50, or 150 micrograms/kg body weight over a period of 7-20 days induced a dose-dependent rise of up to a maximum of a fourfold increase in peripheral WBC counts. The rise in WBC counts was mainly due to elevated neutrophil levels, but an increase in the numbers of monocytes and eosinophils was also observed. However, the rhGM-CSF-induced leukocytosis in dogs was not as dramatic as that observed in nonhuman primates. In all rhGM-CSF-treated dogs, circulating platelet counts dropped to nadir levels of about 20%-30% of normal numbers. Dogs that were treated with 150 micrograms/kg rhGM-CSF developed specific antibodies after about 10-12 days of treatment. These antibodies were able to neutralize the effect of rhGM-CSF in in vitro assays. In vivo WBC counts began to decline when specific antibodies developed, but they never dropped below normal levels. Taken together, the results suggest that human GM-CSF does not appear to exhibit absolute species specificity.     

Persistent aplasia after chemotherapy for acute myeloid leukaemia treated with stem cell transplantation from a matched unrelated donor after dose-reduced conditioning

Persistent aplasia is a rare complication with poor prognosis after intensive chemotherapy for acute leukaemia. A 59-year-old man with acute myeloid leukaemia (AML), was treated after 186 d of chemotherapy-induced persistent aplasia with an allogeneic peripheral blood stem cell transplantation (PBSCT) from a matched unrelated donor (MUD) after dose-reduced conditioning. The patient remains in complete haematological remission more than 8.5 months after haematological recovery. We believe that this is the first reported case of treatment for chemotherapy-induced persistent aplasia with MUD-PBSCT after dose-reduced conditioning, a procedure that can be successfully performed even in elderly patients.     

Comparison of in vivo and in vitro effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with acute myeloid leukemia.

We studied the in vitro effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) in 13 patients with acute myeloid leukemia (AML) and one patient with refractory anemia with excess of blasts in transformation using the AML blast (AML colony-forming units, AML-CFU) and mixed (granulocyte erythrocyte macrophage megakaryocyte colony-forming units, CFU-GEMM) colony culture assays. In parallel, these patients received GM-CSF s.c. at 125 micrograms/m2/day, or in escalated doses starting with 10 micrograms/m2/day for a week or until circulating blast counts reached 50 x 10(9)/liter, in an effort to sensitize leukemic blasts to cell-cycle-specific agents. Results of in vivo GM-CSF treatment were correlated with those of in vitro assays. In 9 of 12 patients (75%), GM-CSF treatment increased peripheral blood blast counts (in vivo effect). GM-CSF also stimulated in vitro AML blast colony proliferation in these nine patients and increased the S+G2M phases of the cell cycle in five out of five of these patients' samples. Two of three patients in whom an in vivo response could not be demonstrated also failed to have a detectable in vitro response. These observations suggest that the AML blast colony culture assay may be useful in predicting the response of AML to cytokine therapy. Finally, GM-CSF stimulated granulocyte-macrophage (granulocyte-macrophage colony-forming units, CFU-GM) and erythroid (erythroid burst-forming units, BFU-E) colony proliferation in 14 and 11 patients, respectively, including the 3 individuals who demonstrated no clinical effect on blast counts. It is, therefore, possible that GM-CSF may be used to stimulate proliferation of progenitors that differentiate into mature granulocyte, monocyte-macrophage, and erythroid cells.     

Sequential in vivo treatment with two recombinant human hematopoietic growth factors (interleukin-3 and granulocyte-macrophage colony-stimulating factor) as a new therapeutic modality to stimulate hematopoiesis: results of a phase I study.

In a phase I study, the sequentially administered combination of recombinant human interleukin-3 (rhIL-3) and rhGM-CSF was compared with treatment with rhIL-3 alone in 15 patients with advanced tumors but normal hematopoiesis. Patients were initially treated with rhIL-3 for 15 days. After a treatment-free interval, the patients received a second 5-day cycle of rhIL-3 at an identical dosage, immediately followed by a 10-day course of rhGM-CSF, to assess the toxicity and biologic effects of this sequential rhIL-3/rhGM-CSF combination. rhIL-3 doses tested were 125, and 250 micrograms/m2, whereas rhGM-CSF was administered at a daily dosage of 250 micrograms/m2. Both cytokines were administered by subcutaneous (SC) bolus injection. rhIL-3/rhGM-CSF treatment was more effective than rhIL-3 but equally effective to each other in increasing peripheral leukocyte counts, especially neutrophilic and eosinophilic granulocyte counts. In contrast, both modes of cytokine therapy raised the platelet counts to the same degree. rhIL-3/GM-CSF treatment was more effective than rhIL-3 in increasing the number of circulating hematopoietic progenitor cells BFU-E and CFU-GM. High-dose rhIL-3, but not low-dose rhIL-3, was as effective as the rhIL-3/rhGM-CSF combinations in increasing the number of circulating CFU-GEMM. The increase in absolute neutrophil counts correlated with the increase in the number of circulating CFU-GM. Side effects, mainly fever, headache, flushing, and sweating, were generally mild, but in two patients the occurrence of chills, rigor, and dyspnea after initiation of GM-CSF treatment necessitated dose reduction and discontinuation, respectively. These results indicate that sequential treatment with rhIL-3 and rhGM-CSF is as effective as single-factor treatment with rhIL-3 in stimulating platelet counts, whereas the effect of combination therapy on neutrophil counts and circulating progenitor cells is superior.     

Cytotoxic effects of dacarbazine in patients with acute myelogenous leukemia: a pilot study.

BACKGROUND AND METHODS. Preclinical studies performed in our laboratory showed that mouse leukemias become highly immunogenic following in vivo treatment with Decarbazine. This observation led to a successful immunochemotherapy protocol in mice using Dacarbazine plus cytoreductive chemotherapy. Therefore an in vivo and in vitro pilot study was conducted in patients (pts) with resistant or relapsed acute myelogenous leukemia (AML). The DNA-repair enzyme O6-alkylguanine-DNA-alkyl-transferase (OGAT) and the in vitro chemosensitivity to Temozolomide, a Dacarbazine derivative, were evaluated in leukemic blasts. RESULTS. Nine pts received Dacarbazine (0.4-0.8 g/sqm/day) on days 0, 1 and 2. On day 7, noticeable blast reduction occurred in 4 pts: pt 1 was in partial remission on day 21, pt 6 still showed bone marrow leukemia, pt 8 died of sepsis on day 8, pt 9 is still in aplasia on day 25. Low OGAT levels and consistent sensitivity to Temozolomide in vitro were found in the blasts of pts responsive to Dacarbazine. Subsequently, pts 1-7 underwent Ara-C (1g/sqm/day) plus Mitoxantrone (6mg/sqm/day) treatment for 6 days. Four pts entered complete remission after 27-45 days of aplasia. Failures were due to hypoplastic death, absolute drug resistance, or hypoplasia followed by blast cell regrowth. CONCLUSIONS. These data point out that Dacarbazine can induce a marked reduction of blast cells as well as severe myelotoxicity in leukemic patients.     

Leucocyte transfusions from rhG-CSF or prednisolone stimulated donors for treatment of severe infections in immunocompromised neutropenic patients

Sepsis in profound neutropenia after chemotherapy is associated with high mortality despite appropriate antibacterial or antifungal treatment. In a prospective phase I/II study we evaluated the feasability and efficacy of leucocyte transfusions (LT) in patients with malignancies or haematological disorders who were suffering from severe bacterial or fungal infection during therapy-related bone marrow aplasia. 30 patients with severe neutropenia and clinical signs of life-threatening sepsis not responding to adequate treatment, received LT from rhG-CSF-stimulated family donors or from prednisolone-primed volunteers. A total of 301 LT were administered. The median number of LT per patient was seven (range three to 65), the median duration of LT treatment was 8 d (range 2-35). The white cell count (WBC), absolute neutrophil count (ANC) and lymphocyte count of the concentrates from rhG-CSF-stimulated donors were significantly higher than those from prednisolone-primed volunteers (P = 0.0001). Despite the critical condition of the patients, LT were generally well tolerated. Only 39 (12.9%) LT were associated with adverse reactions. The transfusion of leucocytes collected by continuous flow leukapheresis from both rhG-CSF and prednisolone stimulated donors resulted in a measurable increment of the peripheral leucocyte and ANC counts in our patients. On day 100 after the first LT, 20/30 patients were alive with complete clearance of the infection.     

Use of oral mucosal neutrophil counts to detect the onset and resolution of profound neutropenia following high-dose myelosuppressive chemotherapy

Severe neutropenia following cytotoxic, anti-cancer chemotherapy is well-known to be associated with an increased risk of infections that may be life-threatening, particularly if not treated immediately. Consequently, serial measurements of neutrophil counts in peripheral blood are done routinely following the administration of high-dose myelosuppressive chemotherapy in order to monitor the onset, severity, and duration of iatrogenic neutropenia. We have studied a non-invasive method of quantifying neutrophils recoverable from the oral mucosa, a normal tissue site of neutrophil turnover, as an alternative approach for monitoring severe, chemotherapy-induced neutropenia. This method is based on the quantification of fluorochrome-stained neutrophils present in timed mouthwash specimens. Blood neutrophil (ANC) and mucosal neutrophil counts (MNC) were measured repeatedly in 23 patients who had been treated with dose-intensive chemotherapy for a variety of indications. All 23 patients developed profound neutropenia (ANC < 100/mm3), and 19 developed neutropenic fever (>101 degrees F) during the 2 weeks following treatment. Nadirs of neutropenia defined by MNC were significantly less prolonged than those defined by the ANC. Furthermore, the onset and resolution of neutropenic fever coincided more precisely with nadirs of neutropenia defined by the MNC than with those defined by the ANC. Our findings indicate that oral mucosal neutrophil counts predict the timing of clinical events associated with neutropenia (e.g., the onset and resolution of fever) with significantly greater accuracy than blood neutrophil counts.     

Hematopoietic recovery following high-dose combined alkylating-agent chemotherapy and autologous bone marrow support in patients in phase-I clinical trials of colony-stimulating factors: G-CSF,GM-CSF,IL-1, IL-2, M-CSF

Summary Hematopoietic recovery in 115 patients with metastatic breast cancer or metastatic melanoma, enrolled in phase-I studies of recombinant growth factors while undergoing treatment with high-dose chemotherapy with autologous bone marrow support, was examined with assays of bone marrow progenitor cells and peripheral blood progenitor cells, and by evaluation of peripheral blood counts. Groups of patients receiving hematopoietic cytokine support [with interleukin-1 (IL-1), interleukin-2 (IL-2), granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage CSF (GM-CSF), or monocyte CSF (M-CSF)] post marrow infusion were compared with contemporaneous control patients not receiving growth factor support. Patients receiving GM-CSF demonstrated statistically significant increases in the growth of granulocyte/macrophage colony-forming units (CFU-GM) in the bone marrow and peripheral blood compared with control patients. The effect of GM-CSF was dose dependent in the early period post marrow infusion (day +6) with bone marrow CFU-GM colonies at doses 8–16 g/kg/ day 34 times those measured in controls. Significant increases in bone marrow multipotential progenitor cells (CFU-GEMM) were seen in patients receiving GMCSF day + 21 post marrow infusion. Patients receiving IL-1 demonstrated significant increases in bone marrow CFU-GM at day +21, maximal at dosages of 24–32 ng/kg/day. There were no significant increases in burst forming unit-erythroid (BFU-E) among any study group. Patients receiving G-CSF had significantly increased absolute neutrophil counts (ANC) and total white blood cell counts (WBC) by day +11 post transplant compared with control patients. Patients receiving GM-CSF demonstrated significantly increased WBC (greater than 2000/mm³) at day +11 and ANC greater than 500/mm³ at day +16. Optimal dose of GCSF and GM-CSF to stimulate neutrophil recovery post transplant was 4–8 g/kg/day and 8–16 g/kg/day, respectively. Platelet recovery did not differ among the six study groups. These data demonstrate accelerated myeloid recovery after high-dose chemotherapy and autologous bone marrow support in patients receiving either G-CSF or GM-CSF. Moreover, GM-CSF and IL-1 stimulate myelopoiesis at the level of bone marrow CFU-GM, while G-CSF causes earlier neutrophil recovery peripherally.This work has been supported in part by The National Heart, Lung, and Blood Institute, grant P01CA47741. Joanne Kurtzberg, MD is a scholar of the Leukemia Society of America     

Differential effects of granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor in children with severe congenital neutropenia.

Severe congenital neutropenia (SCN) is a disorder of myelopoiesis characterized by severe neutropenia secondary to a maturational arrest at the level of promyelocytes. We treated five patients with SCN with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) for 42 days and subsequently, between 1 and 3 months later, with rhG-CSF for 142 days. The objective was to evaluate the safety and ability of these factors to elicit a neutrophil response. rhGM-CSF was administered at a dose of 3 to 30 micrograms/kg/d (30 to 60 minutes, intravenously). In all patients, a specific, dose-dependent increase in the absolute granulocyte counts was observed. However, in four patients this increase was due to an increase in eosinophils, and in only one patient it was due to an increase in the absolute neutrophil counts (ANC). Subsequently, all patients received rhG-CSF at a dose of 3 to 15 micrograms/kg/d subcutaneously. In contrast to rhGM-CSF treatment, all five patients responded to rhG-CSF during the first 6 weeks of treatment with an increase in the ANC to above 1,000/microL. The level of ANC could be maintained during maintenance treatment. In one patient, the increase in ANC was associated with an improvement of a severe pneumonitis caused by Peptostreptococcus and resistant to antibiotic treatment. No severe bacterial infections occurred in any of the patients during CSF treatment. All patients tolerated rhGM-CSF and rhG-CSF treatment without severe side effects. These results demonstrate the beneficial effect of rhG-CSF in SCN patients.     

Treatment of newly diagnosed acute myelogenous leukemia with granulocyte-macrophage colony-stimulating factor (GM-CSF) before and during continuous-infusion high-dose ara-C + daunorubicin: comparison to patients treated without GM-CSF.

We gave 56 patients with newly diagnosed acute myelogenous leukemia (AML) granulocyte-macrophage colony-stimulating factor (GM-CSF) 20 or 125 micrograms/m2 once daily subcutaneously before (for up to 8 days or until GM-CSF-related complications developed) and during, or only during (patients presenting with blast counts greater than 50,000 or other leukemia-related complications) ara-C (1.5 g/m2 daily x 4 by continuous infusion) and daunorubicin (45 mg/m2 daily x 3) chemotherapy. Because results seemed independent of GM-CSF schedule, we compared results in these 56 patients with results in 176 patients with newly diagnosed AML given the same dose and schedule of ara-C without GM-CSF (110 patients ara-C alone, 66 patients ara-C + amsacrine or mitoxantrone). Comparison involved fitting a logistic regression model predicting probability of complete remission (CR) and a Cox regression model to predict survival (most patients in all three studies were dead) with treatment included as a covariate in both analyses. After adjusting for other prognostically significant covariates [presence of an antecedent hematologic disorder, an Inv (16), t(8;21), or abnormalities of chromosomes 5 and/or 7, performance status, age, bilirubin], treatment with ara-C + daunorubicin + GM-CSF was predictive of both a lower CR rate and a lower survival probability. There were no treatment-covariate interactions, suggesting that the negative effect of this GM-CSF treatment regime was not an artifact of some imbalance in patient characteristics. The unadjusted Kaplan-Meier hazard rate of the ara-C + daunorubicin + GM-CSF group was not uniquely high during the initial 4 weeks after start of therapy, but was highest among the three treatment groups throughout weeks 5 to 16, suggesting that the negative effect of this treatment was not caused by acute toxicity. Patients who did not enter CR with this treatment tended to have persistent leukemia rather than prolonged marrow aplasia, suggesting that this treatment and, in particular, GM-CSF may increase resistance of myeloid leukemia cells to chemotherapy. To date, relapse rates are similar in all three groups (P = .43) (as are survival rates once patients are in CR) but much of the remission duration data is heavily censored, unlike the survival data. Our results suggest caution in the use of GM-CSF to sensitize myeloid leukemia cells to daunorubicin + ara-C chemotherapy.     

GM-CSF in the treatment of Fanconi's anaemia

We have used recombinant human (rh) GM-CSF in two 12-year-old Fanconi's aplastic anaemia patients. They had not received any previous therapy except blood transfusions. Each patient was given three 21 d courses of rh-GM-CSF, the first two at a dose of 3.5μg/kg/d and the third at 7 μg/kg/d s.c. There were significant increases in WBC and absolute neutrophil counts after the first week of rh-GM-CSF which lasted as long as the treatment was continued. Following the cessation of treatment, WBC and ANC dropped rapidly. We conclude that rh-GM-CSF can be used in FAA, especially in severely neutropenic cases.     

Recombinant human granulocyte-macrophage colony-stimulating factor ameliorates zidovudine-induced neutropenia in patients with acquired immunodeficiency syndrome (AIDS)/AIDS-related complex.

To evaluate the effect of recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) on patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC) who were intolerant to zidovudine because of neutropenia, we performed a randomized, open-label study in which patients were assigned to one of two groups. Zidovudine was discontinued in group A patients before instituting GM-CSF treatment and was restarted in a graduated fashion over 4 weeks. Group B patients continued on full-dose (1,200 mg/d) zidovudine therapy while beginning GM-CSF therapy. A total of 17 patients were entered, eight in group A and nine in group B. Five of eight patients in group A and seven of nine in group B had a history of Pneumocystis carinii pneumonia (PCP). All were homosexual males, except one female in group A who was the sex partner of a bisexual male with AIDS. All patients had neutropenia (absolute neutrophil count [ANC] less than 1,000/microL) while taking full-dose zidovudine. The mean CD4 (+/- SD) lymphocyte level was 37 (+/- 29)/microL and 39 (+/- 44)/microL in groups A and B, respectively. After randomization, patients were begun on subcutaneous GM-CSF at a dose of 1.0 microgram/kg/d. Patients in group A received 2 weeks of daily GM-CSF, at which time zidovudine was restarted if the ANC was greater than 1,000/microL; if the ANC was less than 1,000/microL, the dose of GM-CSF was increased to 3.0 micrograms/kg, and at 2-week intervals either zidovudine was restarted or the dose of GM-CSF was increased to 5 micrograms/kg and then 10 micrograms/kg, to maintain the ANC greater than 1,000/microL. Group B patients received full-dose zidovudine concurrently with GM-CSF administration. The dose of GM-CSF was increased every 2 weeks if necessary to keep the ANC greater than 1,000/microL while maintaining full-dose zidovudine therapy. Patients in each group showed an increase in total white blood cell (WBC) count. Neutrophils and eosinophils were responsible for the majority of this increase. Patients in group A had a more rapid increase in WBC than those in group B; however, by week 8, the WBC in each group was essentially equal. Viral replication as measured by human immunodeficiency virus (HIV) p24 antigen (Ag) was decreased in four patients in each group, increased in one patient in each group, and remained unchanged in the remainder. The ability to culture virus from peripheral blood mononuclear cells was not changed by the regimen. The major toxicities of the regimen were fever and malaise.(ABSTRACT TRUNCATED AT 400 WORDS)     

Treatment of poor-prognosis, newly diagnosed acute myeloid leukemia with ara-C and recombinant human granulocyte-macrophage colony- stimulating factor

We administered recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) (120 micrograms/m2/d by continuous intravenous [IV] infusion) to 12 patients with newly diagnosed acute myeloid leukemia (AML) at relatively high risk of early death during remission induction. GM-CSF began 3 days after completion of induction chemotherapy (ara-C 1.5 g/m2 d x 4 days by continuous IV infusion after a 3 g/m2 bolus). Rates of fatal infection (42%), pneumonia and/or sepsis (83%), and CR (50%) did not differ significantly (P less than .05) from those observed after administration of the identical chemotherapy without GM-CSF to 53 historical controls with newly diagnosed AML at similarly high risk of early death. There were no significant differences between the GM-CSF-treated and the historical groups in the time required to reach neutrophil counts of 500 or 1,000/microL after administration of chemotherapy. Four patients died of infection before they could have benefited from the earliest recovery of neutrophil count observed in patients who entered CR. Growth of leukemia after GM-CSF administration was observed in only 1 of the 8 patients who survived long enough for response to induction therapy to be fully evaluated. This observation suggests that it might be safe to undertake larger, randomized studies, perhaps using earlier administration of GM-CSF, to definitively determine the role of GM-CSF added to chemotherapy in patients with newly diagnosed AML.     

Analysis of remobilization success in patients undergoing autologous stem cell transplants who fail an initial mobilization: risk factors, cytokine use and cost

Inadequate stem cell mobilization is seen in approximately 25% of patients undergoing autotransplantation for hematologic malignancies. Remobilization strategies include chemotherapy/cytokine combinations or high-dose cytokines alone or in combination. From 1/1997 to 7/2002, we remobilized 86 patients who failed an initial mobilization (median total CD34=0.72 x 10(6)/kg) in sequential cohorts using high-dose G-CSF (32 microg/kg/day) or G-CSF(10 microg/kg/day)+GM-CSF (5 microg/kg/day). No difference in CD34/kg yields were seen (G-CSF alone: 2.2 x 10(6) and G-CSF+GM-CSF 1.6 x 10(6)) in the median 3 aphereses performed (P=0.333). Of the 86, 23 (27%) failed the second mobilization; 14 were remobilized again (yield=1.5 x 10(6) CD34/kg; three aphereses). Of the 86, 93% went to transplant: three progressed, and three had inadequate stem cells. Significant risk factors for a failed remobilization were: number of stem-cell-damaging regimens (P=0.015), time between last chemotherapy and first mobilization (P=0.028), and higher WBC at initiation of first mobilization (P=0.04). High-dose G-CSF (32 microg/kg/day) was more costly @ USD $9,016, vs $5,907 for the G-CSF+GM-CSF combination (P<0.001). Most patients failing an initial mobilization benefit from a cytokine only remobilization. Lower cost G-CSF+GM-CSF is as effective as high-dose G-CSF.     

Stimulation of hematopoiesis in patients with bone marrow failure and in patients with malignancy by recombinant human granulocyte-macrophage colony-stimulating factor

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a multipotential hematopoietin. To assess the toxicity and biological activity of recombinant human GM-CSF (rhGM-CSF) in vivo, 25 patients with malignancy or bone marrow failure were treated with rhGM-CSF (specific activity approximately 5 x 10(7) U/mg) as part of a phase 1 trial. The treatment was administered by continuous intravenous (IV) infusion daily for 2 weeks at fixed dose levels and repeated after a 2- week rest period. Over the entire dose range tested (15 to 500 micrograms/m2/d), rhGM-CSF treatment was associated with dramatic increases (two- to 70-fold) in total leukocyte counts, which consisted predominantly of neutrophils, bands, eosinophils, and monocytes. Furthermore, six of the 14 patients with one or more cytopenias that received at least two cycles of treatment had multilineage responses characterized by twofold or greater increases in platelet count to a level above 100,000, twofold or greater increases in corrected reticulocyte count, and a reduced requirement for red cell transfusions. Three of these patients became independent of both red cell and platelet transfusions for 17 to 37 weeks of follow-up. Treatment was associated also with an increase in bone marrow cellularity and frequency of cycling progenitor cells. The treatment was well tolerated; side effects included constitutional symptoms and bone pain. These results demonstrated that rhGM-CSF has a significant impact on hematopoiesis in patients with advanced malignancy and also in patients with bone marrow failure.     

Prognostic significance of activating FLT3 mutations in younger adults (16 to 60 years) with acute myeloid leukemia and normal cytogenetics: a study of the AML Study Group Ulm

To assess the prognostic relevance of activating mutations of the FLT3 gene in homogeneously treated adults 16 to 60 years of age with acute myeloid leukemia (AML) and normal cytogenetics, pretreatment samples from 224 patients entered into 2 consecutive multicenter treatment trials were analyzed for FLT3 internal tandem duplications (ITDs) and Asp835 mutations. Treatment included intensive double-induction therapy and postremission therapy with high cumulative doses of high-dose cytarabine. ITDs were detected in 32% of the patients and were related to de novo AML and to high white blood cell (WBC) counts, percentages of peripheral blood (PB) and bone marrow (BM) blasts, and serum lactate dehydrogenase levels. Asp835 mutations were present in 14% of the patients and were associated with WBC counts and percentages of PB and BM blasts that were higher than those of patients without FLT3 mutations. With a median follow-up of 34 months, remission duration and overall survival (OS) were significantly shorter for patients with Asp835 mutations or an ITD than for those without FLT3 mutations (P =.03 and P =.0004, respectively). These results were attributable mainly to the negative prognostic effect of FLT3 ITDs. On multivariate analysis, mutant FLT3 was an independent marker affecting remission duration and OS (hazard ratio, 2.35 and 2.11, respectively). Fluorescence in situ hybridization did not detect monoallelic FLT3 deletions in ITD-positive patients. FLT3 mutations identify a subset of young AML patients with normal cytogenetics who do not benefit from intensive chemotherapy, including double-induction and postremission therapy with high-dose cytarabine.     

Secretion of neutrophil secondary granules occurs during granulocyte-macrophage colony stimulating factor induced margination

The effects of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on neutrophil lactoferrin (LF) and transcobalamin (TC) 1 and 3 secretion were determined in vitro and during in vivo administration in humans. In whole blood, in vitro incubation with GM-CSF reproducibly produced a rise in plasma LF concentration (P less than 0.05) whereas in purified neutrophils the results were variable. Exposure of whole blood to GM-CSF also resulted in a significant rise in plasma TC 1 and 3 (190 +/- 60%, P less than 0.05). The response was dose dependent with maximal effect at GM-CSF concentrations of 10 ng/ml and above. rhGM-CSF was administered on seven occasions to six patients with malignant disease prior to chemotherapy. Plasma LF and unsaturated TC 1 and 3 levels rose significantly in each patient studied and the rise coincided with the initial neutropenia due to margination that occurs during infusions of rhGM-CSF. Patients receiving rhGM-CSF may therefore have hypofunctional neutrophils due to secondary granule depletion.