Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is effective in countering chemotherapy-induced neutropenia. However, serum rhG-CSF levels cannot be maintained throughout the course of rhG-CSF therapy. The drop in serum rhG-CSF levels may vary with the duration of rhG-CSF administration or with the circulating neutrophil counts. We investigated the relationship between serum G-CSF levels and circulating neutrophil counts and the pharmacokinetics of rhG-CSF for patients with lung cancer who had been treated with myelosuppressive chemotherapy and then with subcutaneous rhG-CSF (lenograstim, 2 micrograms per kg of body weight per day). Twelve patients were randomly assigned to four groups with different rhG-CSF therapy schedules. Serum G-CSF levels were measured by an enzyme immunoassay method. Serum G-CSF levels during the rhG-CSF therapy greatly exceeded endogenous G-CSF levels and were mainly due to the presence of exogenous rhG-CSF rather than increased levels of endogenous G-CSF. Despite the duration of rhG-CSF administration, serum G-CSF levels during rhG-CSF therapy were inversely correlated with circulating neutrophil counts (r2 = 0.73, P < 0.0001). The value for the area under the concentration-time curve of rhG-CSF on the day of neutrophilia was lower than that on the day of neutropenia (P < 0.05). Our results suggest that the fall in serum G-CSF levels during rhG-CSF therapy may result from increased clearance and/or decreased absorption of rhG-CSF, two processes related to circulating neutrophil counts.
Animal studies suggest that the kidney is involved in the elimination of recombinant human granulocyte colony-stimulating factor (rhG-CSF), which is used for patients with neutropenia during cancer chemotherapy. Since anticancer drugs induce nephrotoxicity, it is important to clarify the role of the kidney in the pharmacokinetics of rhG-CSF in cancer patients. Our study was designed to evaluate the relationship between the pharmacokinetics of rhG-CSF and renal function in lung cancer patients compared to the absolute neutrophil count (ANC). The pharmacokinetic studies were conducted with 25 lung cancer patients. Following chemotherapy using platinum-based compounds, a bolus 5 μg of rhG-CSF/kg of body weight was intravenously injected from the first day of leukopenia or neutropenia. Pharmacokinetic parameters were estimated by fitting the concentration in serum-time data to a two-compartment model according to the population pharmacokinetics and the Bayesian method. Creatinine clearance (CLCR) was predicted by the Cockcroft-Gault formula. rhG-CSF clearance (CLG-CSF) correlated significantly with the ANC (r = 0.613; P < 0.001) and CLCR (r = 0.632; P < 0.001). Multiple linear regression analysis showed that the combination of the ANC and CLCR accounted for 57.4% of the variation of CLG-CSF. In patients with an ANC of <1,000/μl, CLCR accounted for 72.9% of the variation of CLG-CSF (P < 0.001). Our findings suggest that renal function and neutrophil counts correlate with CLG-CSF and that the role of renal function in eliminating rhG-CSF is important in lung cancer patients with neutropenia.
The aim of the present study was to investigate the efficacy and side-effects of preventive treatment with pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) on concurrent chemoradiotherapy-induced grade IV neutropenia and to provide a rational basis for its clinical application. A total of 114 patients with concurrent chemoradiotherapy-induced grade IV neutropenia were enrolled. A randomized approach was used to divide the patients into an experimental group and a control group. The experimental group included three subgroups, namely a P-50 group, P-100 group and P + R group. The P-50 group had 42 cases, which were given a single 50-μg/kg subcutaneous injection of PEG-rhG-CSF. The P-100 group had 30 cases, which received a single 100-μg/kg subcutaneous injection of PEG-rhG-CSF. The P + R group comprised 22 cases, which were given a single 50-μg/kg subcutaneous injection of PEG-rhG-CSF and rhG-CSF 5 μg/kg/day; when the absolute neutrophil count (ANC) was ≥2.0×109/l, the administration of rhG-CSF was stopped. The control group (RC group) comprised 20 patients, who received rhG-CSF 5 μg/kg/day by subcutaneous injection until the ANC was ≥2.0×109/l. Changes in the neutrophil proliferation rate and ANC values over time, the neutropenic symptom remission time and incidence of adverse drug reactions were analyzed statistically in each group of patients. In the experimental group, the neutrophil proliferation rate and ANC values were significantly higher than those in the control group; the clinical effects began 12–24 h after treatment in the experimental group, and indicated that the treatment improved neutropenia in ~48 h after treatment. There was no significant difference in the neutrophil proliferation rate and ANC values between the P-50 and P+R groups. In the experimental group, the remission time of neutropenia-induced fever and muscle pain after administration was significantly shorter than that in the control group, with a statistically significant difference (P<0.05). The adverse drug reaction rates showed no significant difference between the experimental group and the control group. PEG-rhG-CSF had good efficacy and safety in the treatment of concurrent chemotherapy-induced grade IV neutropenia. For the treatment of concurrent chemotherapy-induced grade IV neutropenia, a single subcutaneous injection of 50 μg/kg PEG-rhG-CSF is the recommended dose. The effects begin at 12–24 h; if the ANC values are not significantly improved during this time, no supplementary administration of rhG-CSF is necessary.
pegylated recombinant human granulocyte colony-stimulating factor; concurrent chemoradiotherapy; grade IV neutropenia
We examined the in vivo effects of recombinant human granulocyte colony- stimulating factor (rhG-CSF) in primates (cynomolgus monkeys) treated with subcutaneous doses of rhG-CSF for 14-28 d. A dose-dependent increase in the peripheral white blood cells (WBC) was seen, reaching a plateau after 1 wk of rhG-CSF treatment. The elevation of WBC was due to an increase in the absolute neutrophil count. These results demonstrate that rhG-CSF is a potent granulopoietic growth and differentiation factor in vivo. In cyclophosphamide (CY)-induced myelosuppression, rhG-CSF was able to shorten the time period of WBC recovery in two treated monkeys to 1 wk, as compared to more than 4 wk for the control monkey. Its ability to significantly shorten the period of chemotherapy-induced bone marrow hypoplasia may allow clinicians to increase the frequency or dosage of chemotherapeutic agents. In addition, the increase in absolute numbers of functionally active neutrophils may have a profound effect in the rate and severity of neutropenia-related sepsis. Furthermore, the activities reported here indicate a potential role for rhG-CSF in the treatment of patients with myelodysplastic syndrome, congenital agranulocytosis, radiation-induced myelosuppression, and bone marrow transplantation.
Twelve patients with advanced small cell carcinoma of the bronchus were treated by continuous infusion of recombinant human granulocyte colony-stimulating factor (rhG-CSF) at the following dose levels: 1 microgram, 5 micrograms, 10 micrograms, 20 micrograms and 40 micrograms kg-1 day-1 for 5 days. No toxicities resulted from the treatment and in all 12 patients the number of peripheral neutrophils increased rapidly to a maximum of 100 x 10(9) l-1 at 10 micrograms kg-1 day-1. The neutrophils were shown to be functionally normal in tests of their mobility and bactericidal activity. During the phase II part of the study the patients were treated by a combination of intravenous adriamycin 50 mg m-2, ifosfamide 5 g m-2 by i.v. infusion with mesna 8 g m-2 on day 1, and etoposide 120 mg m-2 on days 1, 2 and 3 also intravenously. The chemotherapy regime was repeated every 3 weeks. RhG-CSF was given to each patient for 14 days on alternate cycles of chemotherapy and reduced the period of absolute neutropenia considerably (median of 80%), with a return to normal, or above normal, neutrophil counts within 2 weeks after day 1 of chemotherapy. Six severe infective episodes were observed during the cycles of chemotherapy which did not include rhG-CSF, while no infective episodes occurred when patients were treated with rhG-CSF. These results demonstrate the utility of rhG-CSF in restoring functional neutrophils to patients undergoing intensive chemotherapy.
Normal dogs were treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF) at 10 micrograms/kg/day for 30 d, which caused an initial neutrophilia, followed by a prolonged period of chronic neutropenia. A control dog treated with recombinant canine G-CSF (rcG-CSF) showed persistent neutrophilia over 3 mo. Serum from dogs during neutropenia contained an antibody to rhG-CSF, which neutralized the stimulatory effects of both rhG-CSF and rcG-CSF on dog marrow neutrophilic progenitor cell growth and on NFS-60 cell proliferation. 4 mo after discontinuation of rhG-CSF, the dogs' neutrophil counts returned to the normal range. Rechallenge with the rhG-CSF re-induced severe neutropenia in 1 wk. Neutropenia was transferred by plasma infusion from a neutropenic dog to a previously normal dog. These data suggest that human rhG-CSF immunizes normal dogs and thereby induces neutralization of endogenous canine G-CSF and neutropenia. This model system should allow more precise definition of the in vivo role of G-CSF.
The effects of altering the timing of recombinant human granulocyte colony-stimulating factor (rhG-CSF) administration on neutropenia induced by cyclophosphamide (CPA) were studied experimentally in a mouse model. Experimental mice were divided into three groups: (a) treatment with rhG-CSF after CPA administration (post-treatment group); (b) treatment with rhG-CSF both before and after CPA administration (pre- and post-treatment group); and (c) treatment with saline after CPA administration (control group). The results were as follows. Mice receiving rhG-CSF on the 2 days preceding CPA treatment, in which progenitor cell counts outside the S-phase when CPA was administered were the lowest of all the groups, showed accelerated neutrophil recovery but decreased neutrophil nadirs compared with the control group despite rhG-CSF treatment. The pre- and post-treatment group, consisting of mice who received rhG-CSF treatment on days -4 and -3 before CPA treatment, and in which progenitor cell counts when CPA was administered were increased to greater levels than in the other groups, showed remarkably accelerated neutrophil recovery and the greatest increase in the neutrophil nadirs of all the groups. These results suggested that the kinetics of progenitor cell populations when chemotherapeutic agents were administered seemed to play an important role in neutropenia after chemotherapy, and that not only peripheral neutrophil cell and total progenitor cell counts but also progenitor cell kinetics should be taken into consideration when administering rhG-CSF treatment against the effects of chemotherapy.
Biopharmaceutical drugs are mainly recombinant proteins produced by biotechnological tools. The patents of many biopharmaceuticals have expired, and biosimilars are thus currently being developed. Human granulocyte colony stimulating factor (hG-CSF) is a hematopoietic cytokine that acts on cells of the neutrophil lineage causing proliferation and differentiation of committed precursor cells and activation of mature neutrophils. Recombinant hG-CSF has been produced in genetically engineered Escherichia coli (Filgrastim) and successfully used to treat cancer patients suffering from chemotherapy-induced neutropenia. Filgrastim is a 175 amino acid protein, containing an extra N-terminal methionine, which is needed for expression in E. coli. Here we describe a simple and low-cost process that is amenable to scaling-up for the production and purification of homogeneous and active recombinant hG-CSF expressed in E. coli cells.
Here we describe cloning of the human granulocyte colony-stimulating factor coding DNA sequence, protein expression in E. coli BL21(DE3) host cells in the absence of isopropyl-β-D-thiogalactopyranoside (IPTG) induction, efficient isolation and solubilization of inclusion bodies by a multi-step washing procedure, and a purification protocol using a single cationic exchange column. Characterization of homogeneous rhG-CSF by size exclusion and reverse phase chromatography showed similar yields to the standard. The immunoassay and N-terminal sequencing confirmed the identity of rhG-CSF. The biological activity assay, in vivo, showed an equivalent biological effect (109.4%) to the standard reference rhG-CSF. The homogeneous rhG-CSF protein yield was 3.2 mg of bioactive protein per liter of cell culture.
The recombinant protein expression in the absence of IPTG induction is advantageous since cost is reduced, and the protein purification protocol using a single chromatographic step should reduce cost even further for large scale production. The physicochemical, immunological and biological analyses showed that this protocol can be useful to develop therapeutic bioproducts. In summary, the combination of different experimental strategies presented here allowed an efficient and cost-effective protocol for rhG-CSF production. These data may be of interest to biopharmaceutical companies interested in developing biosimilars and healthcare community.
Recombinant human granulocyte colony-stimulating factor (rhG-CSF) was administered at a dose of 1-60 micrograms/kg of body weight to 22 patients with transitional cell carcinoma before chemotherapy as part of a Phase I/II study. In all patients, a specific dose-dependent increase in the absolute neutrophil count (ANC) of 1.8-12 fold was seen. In addition, this augmentation in the ANC was accompanied by an increase in leukocyte alkaline phosphatase, a marker of secondary granule formation. In six of eight patients analyzed, an increase in bone marrow myeloid to erythroid cell ratio was seen. Day 14 peripheral blood cell derived colony forming unit granulocyte macrophage were also increased by day 6 of rhG-CSF treatment. Circulating levels of eosinophils and basophils were unchanged; however, a 10-fold increase in monocytes was observed in patients treated at the highest doses. There was also a small increase in CD3+ lymphocytes that was not dose dependent. Hemoglobin, hematocrit, and platelet count remained near baseline throughout the period of rhG-CSF administration. These findings demonstrate that rhG-CSF is a potent stimulus for normal neutrophil proliferation and maturation.
objective was to investigate the safety of recombinant human
granulocyte colony stimulating factor (rhG-CSF) for the treatment of
very low birthweight infants (VLBW) with sepsis and relative
neutropenia, specifically with regard to worsening of respiratory
distress and thrombocytopenia and all cause mortality. Secondary
objectives were to evaluate duration of ventilation, intensive care,
and antibiotic use as markers of efficacy.
(⩽ 28 days) in intensive care, with birth weights of 500-1500 g,
absolute neutrophil count (ANC) of ⩽ 5 × 109/l, and
clinical evidence of sepsis, were randomly assigned to receive either
rhG-CSF (10 µg/kg/day) administered intravenously (n = 13), or
placebo (n = 15) for a maximum of 14 days, in addition to standard
treatment and antibiotics. All adverse events, oxygenation index,
incidence of thrombocytopenia, all cause mortality, duration of
ventilation, intensive care and antibiotic treatment, and ANC recovery
were compared between the two groups.
and oxygenation index were not increased by, and thrombocytopenia was
not attributable to, treatment with rhG-CSF. At 6 and 12 months
postmenstrual age, there were significantly fewer deaths in the group
receiving rhG-CSF (1/13 v 7/15;
p ⩽ 0.038). There was a non-significant trend towards a reduction in duration of ventilation, intensive care, and antibiotic use in the
rhG-CSF group. There was a significantly more rapid increase in ANC in
the rhG-CSF treated babies (p < 0.001).
CONCLUSIONS—In a small
randomised placebo controlled trial in a highly selected group of
neonates, adjuvant treatment with rhG-CSF increased ANC rapidly, and no
treatment related adverse events were identified. Mortality at 6 and 12 months postmenstrual age was significantly lower in the treatment
group. A large trial investigating efficacy in a similar group of
neonates is warranted.
Recombinant human Granulocyte-Colony Stimulating Factor (rhG-CSF) supplementation seems to be a promising innovative therapy in reproductive medicine, used in case of recurrent miscarriage, embryo implantation failure or thin endometrium, although its mechanisms of action remain unknown. Our aim was to identify possible endometrial pathways influenced by rhG-CSF.
Materials and Methods
Hypothetical molecular interactions regulated by G-CSF were designed through a previous large scale endometrial microarray study. The variation of endometrial expression of selected target genes was confirmed in control and infertile patients. G-CSF supplementation influence on these targets was tested on an endometrial ex-vivo culture. Middle luteal phase endometrial biopsies were cultured on collagen sponge with or without rhG-CSF supplementation during 3 consecutive days. Variations of endometrial mRNA expression for the selected targets were studied by RT-PCR.
At the highest dose of rhG-CSF stimulation, the mRNA expression of these selected target genes was significantly increased if compared with their expression without addition of rhG-CSF. The selected targets were G-CSF Receptor (G-CSFR), Integrin alpha-V/beta-3 (ITGB3) implicated in cell migration and embryo implantation, Plasminogen Activator Urokinase Receptor (PLAUR) described as interacting with integrins and implicated in cell migration, Thymidine Phosphorylase (TYMP) implicated in local angiogenesis, CD40 and its ligand CD40L involved in cell proliferation control.
RhG-CSF seems able to influence endometrial expressions crucial for implantation process involving endometrial vascular remodelling, local immune modulation and cellular adhesion pathways. These variations observed in an ex-vivo model should be tested in-vivo. The strict indications or counter indication of rhG-CSF supplementation in reproductive field are not yet established, while the safety of its administration in early pregnancy on early embryogenesis still needs to be demonstrated. Nevertheless, rhG-CSF appears as a promising therapy in some difficult and unsolved cases of reproductive failure. Indications of pre-conceptual rhG-CSF supplementation may derive from a diagnosed lack of endometrial expression of some target genes.
The direct effects of human granulocyte colony-stimulating factor (hG-CSF) on mature polymorphonuclear neutrophils (PMNs) in vitro were studied with regard to chemotaxis, superoxide production, and phagocytosis and microbicidal activity against the following viable microorganisms: Staphylococcus aureus, serum-resistant Pseudomonas aeruginosa, and Candida albicans. Recombinant hG-CSF (rhG-CSF) acted as a chemoattractant for human PMNs in a dose-dependent manner. The chemotactic response of PMNs to N-formyl-methionyl-leucyl-phenylalanine (FMLP) was not enhanced by rhG-CSF at any of the concentrations used. rhG-CSF did not induce the generation of superoxide by itself. However, rhG-CSF was able to prime human PMNs and to enhance O2- release stimulated by FMLP in a dose-dependent manner. rhg-CSF did not enhance phagocytosis or killing of the three species of microorganisms by normal PMNs. With PMNs obtained from patients who had hematological disorders or solid tumors, no enhancement of the microbicidal activity was observed in most cases. Microbial killing mediated by PMNs depended on the ratio of PMNs to target organisms. We concluded from these facts that the most important effect of rhG-CSF was to increase the number of the peripheral PMNs and not to enhance the functions of mature PMNs.
Twelve patients with small cell lung cancer were treated with recombinant human granulocyte colony-stimulating factor, rhG-CSF, given by continuous infusion at doses ranging from 1 to 40 micrograms kg-1 day-1. Patients received the rhG-CSF before the start of intensive chemotherapy and after alternate cycles of chemotherapy. Several in vitro assays were performed using peripheral blood neutrophils and marrow progenitor cells collected from patients prior to and after infusion of the growth factor. Peripheral blood neutrophils were tested for mobility and phagocytic activity. In addition, in vitro clonogenic assays of marrow haemopoietic progenitor cells and analysis of bone marrow trephines and aspirates were carried out. We found that rhG-CSF in vivo has at least two main effects: (a) an early fall in peripheral neutrophils, within the first hour, followed by a rapid influx of mature neutrophils into the circulatory pool; (b) stimulation of proliferation and differentiation of neutrophil precursors in the bone marrow. Neutrophils released into the circulation were normal in tests of their mobility and phagocytic activity.
To investigate effects of recombinant human erythropoietin (rhEPO) plus recombinant human granulocyte colony stimulating factor (rhG-CSF) on mobilization of CD90+CD34− and Sca-1+ stem cells in mice. rhEPO 1000 IU·kg−1·d−1 per mice alone or plus rhG-CSF 250 μg·kg−1·d-1−1per mice was administered to mice for five days, the peripheral blood was collected at 6 hours, 1, 3,5 and 7 days after the last administration. The number of white blood cells (WBC) and mononuclear cells (MNC) was counted. The level of CD34, CD90 and Sca-1 mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR).The expressions of CD90+CD34− in absolute nuclear cells of peripheral blood was detected by flow cytometry. The results indicate that compared to mobilizing by rhG-CSF, rhEPO or plus rhG-CSF did not significantly enhance the number of WBC and MNC, on the fifth and the seventh day after the last administration, both the expression of CD34,CD90 and Sca-1 mRNA and the proportion of CD90+CD34− cells dramatically raised in rhEPO or in addition to rhG-CSF groups. We conclude that rhEPO or plus rhG-CSF had a strong capacity of mobilization of stem cells. The alteration of expression of CD34, CD90 and Sca-1 mRNA after the administration of rhEPO or combined with rhG-CSF indicated that this agents might potentially alter the peripheral blood graft content.
Erythropoietin; Granulocyte-colony stimulating factor; Mobilization; Peripheral blood; Stem cells
Granulocyte colony-stimulating factor (G-CSF) has exhibited efficacy at preventing the progression of pulmonary hypertension (PH); however, the exact mechanism is not completely clear. The aim of the present study was to assess whether this protective effect was mediated by the upregulation of circulating endothelial progenitor cells (EPCs) via the nitric oxide (NO) system. PH was induced in male Sprague-Dawley (SD) rats by the administration of a single subcutaneous injection of monocrotaline (MCT). The rats were treated with recombinant human G-CSF (rhG-CSF, 50 μg/kg/day) by subcutaneous injection from day five to day seven subsequent to the injection of MCT. Nω-nitro-L-arginine methyl ester (L-NAME, 4 mg/kg/day) was intragastrically administered in addition to rhG-CSF as a negative intervention. The changes in hemodynamics and histology, the number and function of circulating EPCs and the concentration of plasma NO were evaluated. With the occurrence of PH in the rat model, the number and function of circulating EPCs were demonstrated to be markedly downregulated. Moreover, a reduced plasma concentration of NO was observed, which was positively correlated with the number of circulating EPCs. Administration of rhG-CSF elevated the plasma level of NO, upregulated the number and function of circulating EPCs and effectively improved pulmonary hemodynamics and vascular reconstruction. Furthermore, the positive correlation between the levels of plasma NO and circulating EPCs was also observed in the rhG-CSF treatment group. However, the protective effect of rhG-CSF in PH was attenuated by L-NAME, which mediated the downregulation of NO and the EPCs. Thus, the present study suggests that G-CSF may attenuate the progression of MCT-induced PH by improving vascular injury repair mechanisms via the NO-mediated upregulation of EPCs.
pulmonary hypertension; model; endothelial progenitor cells; nitric oxide; granulocyte colony-stimulating factor; hemodynamics
Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is widely used to treat neutropenia during cytotoxic chemotherapy. The optimal scheduling of rhG-CSF is unknown and can hardly be tested in clinical studies due to numerous therapy parameters affecting outcome (chemotherapeutic regimen, rhG-CSF schedules, individual covariables). Motivated by biomathematical model simulations, we aim to investigate different rhG-CSF schedules in a preclinical chemotherapy mouse model.
The time course of hematotoxicity was studied in CD-1 mice after cyclophosphamide (CP) administration. Filgrastim was applied concomitantly in a 2 × 3-factorial design of two dosing options (2 × 20 μg and 4 × 10 μg) and three timing options (directly, one, and two days after CP). Alternatively, a single dose of 40 μg pegfilgrastim was applied at the three timing options. The resulting cytopenia was compared among the schedules.
Dosing and timing had a significant influence on the effectiveness of filgrastim schedules whereas for pegfilgrastim the timing effect was irrelevant. The best filgrastim and pegfilgrastim schedules exhibited equivalent toxicity. Monocytes dynamics performed analogously to granulocytes. All schedules showed roughly the same lymphotoxicity.
We conclude that effectiveness of filgrastim application depends heavily on its scheduling during chemotherapy. There is an optimum of timing. Dose splitting is better than concentrated applications. Effectiveness of pegfilgrastim is less dependent on timing.
rhG-CSF; chemotherapy toxicity; mice; cyclophosphamide; cytopenia; neutropenia
Objective: The aim of the present study was to investigate the differences
between therapeutic granulocyte-colony stimulating factor (G-CSF) cycles and prophylactic
G-CSF cycles in patients receiving paclitaxel and carboplatin combination chemotherapy for
Material and Method: Medical records of 15 women who received paclitaxel and
carboplatin combination chemotherapy for ovarian cancer between January 2003 and December
2012 were analyzed retrospectively. All 15 patients completed 6 cycles of paclitaxel and
carboplatin as the first-line chemotherapy. The complications were compared between
therapeutic G-CSF cycles and prophylactic G-CSF cycles.
Results: The number of chemotherapy cycles correlated with the ratio of
prophylactic G-CSF cycles. It was considered that earlier prophylactic G-CSF injections
were chosen due to a gradual decrease in WBC and neutrophil counts. The WBC and neutrophil
counts were significantly higher in prophylactic G-CSF cycles than in therapeutic G-CSF
cycles. However, there were no significant differences in the intervals of chemotherapy,
delay of chemotherapy, and incidence of febrile neutropenia between the therapeutic G-CSF
and prophylactic G-CSF cycles.
Conclusion: Prophylactic G-CSF injections were not effective in preventing
the incidence of febrile neutropenia in patients receiving paclitaxel and carboplatin
combination chemotherapy for ovarian cancer.
granulocyte-colony stimulating factor (G-CSF); ovarian cancer; paclitaxel and carboplatin combination chemotherapy
The differentiation and maturation of hematopoietic progenitor cells are regulated by certain growth factors. Several of these glycoproteins have been characterized, and their amino acid sequences have been delineated. Modern DNA technology provides sufficient quantities of these hormones for testing in clinical trials. Erythropoietin (EPO) has been shown to increase the hemoglobin level and hematocrit in patients with end-stage renal disease. Granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF) can increase the numbers of neutrophils and monocytes, in a dose-dependent fashion. The function of granulocytes and monocytes is also enhanced. Clinical studies of the toxicity and activity of G-CSF and GM-CSF have been conducted in patients with acquired immune deficiency syndrome, aplastic anemia, myelodysplastic syndromes, and neutropenia due to cancer and chemotherapy. In almost all patients the neutrophil count increased within 24 hours after the start of treatment. Side effects of G-CSF and GM-CSF are infrequent and usually mild. Combinations of CSFs may be even more effective.
Granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony stimulating factor (GM-CSF) are the two most commonly used cytokines for mobilization of stem cells in patients undergoing high dose chemotherapy with stem cell support. Both cytokines increase the peripheral blood white blood cell count and the stem cell count but there are other differences in the stem cell products mobilized by G-CSF versus those mobilized with GM-CSF. Generally higher numbers of dendritic cells are mobilized with GM-CSF than by G-CSF. The primary objective of this randomized study was to evaluate the safety and efficacy of chemotherapy plus G-CSF versus chemotherapy plus G-CSF and GM-CSF in patients with B-cell non-Hodgkin’s lymphoma (NHL) who were undergoing chemo-mobilization. Secondary objectives were to determine the expression of various dendritic cell subsets in the two groups and to determine the incidence of disease progression or relapse at 12 months.
We prospectively evaluated 84 patients with relapsed NHL who were candidates for high dose therapy (HDT). All patients underwent chemo-mobilization using ifosfamide, etoposide, and rituximab. All patients were randomized in an adaptive manner to receive either G-CSF or G-CSF plus GM-CSF (G+GM) starting 24 hours after completion of chemotherapy and continuing until completion of apheresis. The stem cell yield/kg, the number of apheresis procedures needed in the two groups, and the toxicity were recorded. We also enumerated dendritic cell subsets, myeloid DCs (mDC) and plasmacytoid DCs (pDC), in apheresis products and in peripheral blood (PB) samples collected pre-chemotherapy. The data were expressed as a percentage of peripheral blood mononuclear cells.
A total of 84 patients were treated. Forty-three patients received G-CSF and 41 received G+GM. Both regimens were well tolerated. The median CD34+ cell dose collected was similar in the two groups. A total of 54 (G-CSF N = 25 and G+GM N = 29) paired samples from baseline and post-apheresis were available for analysis of dendritic cell subsets. There was no significant difference in the percentages of mDC subsets between baseline and post-apheresis collected with G-CSF or G+GM mobilization. However, there was a significant increase in the percentage of pDC subsets in the G-CSF alone when compared to the G+GM arm (P = 0.002). Furthermore, the ratio of mDC and pDC was significantly lower after mobilization with G-CSF versus G+GM (P = 0.029).
Addition of GM-CSF to G-CSF to the mobilization regimen resulted in lower percentages of pDC in the apheresis products when compared to those with G-CSF alone. This shifts the mDC/pDC ratio in the apheresis grafts in favor of mDC in the combination arm. However, these differences did not seem to impact the clinical outcomes in the two groups. (ClinicalTrials.gov Identifier: NCT00499343).
lymphoma; filgrastim; sargramostim; stem cell mobilization
Sixty-three patients with extensive-stage small-cell lung cancer were randomized to receive either cyclophosphamide, vincristine, doxorubicin and etoposide (CODE) alone or CODE plus recombinant human granulocyte colony-stimulating factor (rhG-CSF). rhG-CSF administration in support of CODE chemotherapy resulted in increased mean total received dose intensity for all drugs (P = 0.03) with a significant improvement in survival (P = 0.004).
Granulocyte-colony stimulating factor (G-CSF) is a pleiotropic cytokine that stimulates the development of committed hematopoietic progenitor cells and enhances the functional activity of mature cells. Here, we report a simplified method for fed-batch culture as well as the purification of recombinant human (rh) G-CSF. The new system for rhG-CSF purification was performed using not only temperature shift strategy without isopropyl-l-thio-β-d-galactoside (IPTG) induction but also the purification method by a single step of prep-HPLC after the pH precipitation of the refolded samples. Through these processes, the final cell density and overall yield of homogenous rhG-CSF were obtained 42.8 g as dry cell weights, 1.75 g as purified active proteins, from 1 L culture broth, respectively. The purity of rhG-CSF was finally 99% since the isoforms of rhG-CSF could be separated through the prep-HPLC step. The result of biological activity indicated that purified rhG-CSF has a similar profile to the World Health Organization (WHO) 2nd International Standard for G-CSF. Taken together, our results demonstrate that the simple purification through a single step of prep-HPLC may be valuable for the industrial-scale production of biologically active proteins.
No published data are available concerning the activity and tolerability of intramuscularly administered granulocyte colony-stimulating factor (G-CSF) in humans. To fill this gap, 19 patients with advanced ovarian cancer previously treated with at least one first-line chemotherapy cycle received the following myelosuppressive regimen: mitoxantrone (DHAD) 12 mg m-2 i.v. on day 1; ifosfamide (IFO) 4 g m-2 i.v. on days 1 and 2; mesna 800 mg m-2 i.v. t.i.d. on days 1 and 2. G-CSF (Filgrastim) was given at a dose of 5 micrograms/kg/day i.m. from day 6 to day 19, its pharmacokinetics being assessed in five patients. The neutrophil nadir was observed after a mean period of 8 days, and the neutrophil count was < 1.0 x 10(3) mm-3 for a mean of 6 days during the cycle of chemotherapy. The neutrophil count fell after the withdrawal of G-CSF on the 19th day of treatment. The difference in absolute neutrophil count between day 19 and day 21 was statistically significant (P = 0.0001); nevertheless, at day 21 no WHO grade 3-4 neutropenia was reported. DHAD and IFO were respectively given at 95% and 93% of the planned dose. The pharmacokinetics of G-CSF i.m. seems to be similar to that of the drug given subcutaneously. No evidence of cumulative myelosuppression was observed. G-CSF was well tolerated and no complications were observed at the injection sites. In conclusion, if the results obtained in this pilot study regarding the activity of i.m. G-CSF are confirmed by a randomised trial, the intramuscular administration of G-CSF could become a valid alternative for patients who dislike the subcutaneous route and who are being treated with chemotherapy that does not induce profound thrombocytopenia.
In a pilot study recombinant human granulocyte colony-stimulating factor (rhG-CSF) was administered to 12 neutropenic preterm infants to determine if neonatal neutropenia is secondary to decreased endogenous G-CSF production. Respiratory variables were monitored because of the possible link between inflammatory cells and hyaline membrane disease. All infants showed increased neutrophil counts. The only possible side effect observed was an exacerbation of thrombocytopenia.
Granulocyte colony-stimulating factor (G-CSF) is effective in accelerating neutrophil recovery after intensive chemotherapy for acute myeloid leukemia (AML). However, the optimal G-CSF dosage for patients with AML has not been determined. To our knowledge, G-CSF dosages have not been compared in a randomized AML study.
Patients enrolled on the St. Jude AML97 protocol who remained on study after window therapy were eligible to participate. The effect of the dosage of G-CSF given after induction chemotherapy courses 1 and 2 was analyzed in 46 patients randomly assigned in a double-blinded manner to receive 5 or 10 μg/kg/day of G-CSF. The number of days of G-CSF treatment, neutropenia (absolute neutrophil count < 0.5 × 109/L), and hospitalization; the number of episodes of febrile neutropenia, grade 2-4 infection, and antimicrobial therapy; transfusion requirements; the cost of supportive care; and survival were compared between the two study arms.
We found no statistically significant difference between the two arms in any of the endpoints measured.
The higher G-CSF dosage (10 μg/kg/day) offers no greater benefit than the lower dosage (5 μg/kg/day) in patients undergoing intensive chemotherapy for AML.
acute myeloid leukemia; granulocyte colony-stimulating factor; dosage; children; randomized trial
Granulocyte colony stimulating factor (G-CSF) regulates survival, proliferation, and differentiation of neutrophilic granulocyte precursors, Recombinant G-CSF has been used for the treatment of congenital and therapy-induced neutropenia and stem cell mobilization. Due to its intrinsic instability, recombinant G-CSF needs to be excessively and/or frequently administered to patients in order to maintain a plasma concentration high enough to achieve therapeutic effects. Therefore, there is a need for the development of G-CSF derivatives that are more stable and active in vivo.
Using site-direct mutagenesis and recombinant DNA technology, a structurally modified derivative of human G-CSF termed G-CSFa was obtained. G-CSFa contains alanine 17 (instead of cysteine 17 as in wild-type G-CSF) as well as four additional amino acids including methionine, arginine, glycine, and serine at the amino-terminus. Purified recombinant G-CSFa was tested for its in vitro activity using cell-based assays and in vivo activity using both murine and primate animal models.
In vitro studies demonstrated that G-CSFa, expressed in and purified from E. coli, induced a much higher proliferation rate than that of wild-type G-CSF at the same concentrations. In vivo studies showed that G-CSFa significantly increased the number of peripheral blood leukocytes in cesium-137 irradiated mice or monkeys with neutropenia after administration of clyclophosphamide. In addition, G-CSFa increased neutrophil counts to a higher level in monkeys with a concomitant slower declining rate than that of G-CSF, indicating a longer half-life of G-CSFa. Bone marrow smear analysis also confirmed that G-CSFa was more potent than G-CSF in the induction of granulopoiesis in bone marrows of myelo-suppressed monkeys.
G-CSFa, a structurally modified form of G-CSF, is more potent in stimulating proliferation and differentiation of myeloid cells of the granulocytic lineage than the wild-type counterpart both in vitro and in vivo. G-CSFa can be explored for the development of a new generation of recombinant therapeutic drug for leukopenia.