Haemopoietic growth factors in paediatric oncology: a review of the literature

The Safety Profile of Filgrastim and Pegfilgrastim

The discovery of endogenous proteins that regulate hematopoiesis led to the identification of human granulocyte colony-stimulating factor (G-CSF). With the advent of recombinant DNA technology, it became possible to manufacture bioactive recombinant proteins for medicinal use. Since the approval of recombinant human G-CSF (rHuG-CSF), such as filgrastim in 1991 and pegfilgrastim in 2002, millions of patients at risk for severe myelosuppression have received these products. Overall, filgrastim and pegfilgrastim have a high margin of safety for short-term use; however, rare severe adverse events have emerged and questions remain regarding the long-term safety and consequences of use of these products. This chapter primarily focuses on the safety and adverse event profile of the most widely used commercially available rHuG-CSF, Neupogen (filgrastim) and Neulasta [a modified (pegylated) filgrastim, pegfilgrastim]. As safety information can change rapidly, we suggest readers consult the latest package inserts for any changes that have occurred from the time of this writing. Other chapters in this volume discuss key studies in specific disease settings in greater detail than is the purview of this chapter, and we encourage the interested reader to reference them for further information.

Randomized Trial of Prophylactic Granulocyte Colony-Stimulating Factor During Rapid COJEC Induction in Pediatric Patients With High-Risk Neuroblastoma: The European HR-NBL1/SIOPEN Study

Purpose

To reduce the incidence of febrile neutropenia during rapid COJEC (cisplatin, vincristine, carboplatin, etoposide, and cyclophosphamide given in a rapid delivery schedule) induction. In the High-Risk Neuroblastoma-1 (HR-NBL1) trial, the International Society of Paediatric Oncology European Neuroblastoma Group (SIOPEN) randomly assigned patients to primary prophylactic (PP) versus symptom-triggered granulocyte colony-stimulating factor (GCSF; filgrastim).

Patients and Methods

From May 2002 to November 2005, 239 patients in 16 countries were randomly assigned to receive or not receive PPGCSF. There were 144 boys with a median age of 3.1 years (range, 1 to 17 years) of whom 217 had International Neuroblastoma Staging System (INSS) stage 4 and 22 had stage 2 or 3 MYCN-amplified disease. The prophylactic arm received a single daily dose of 5 μg/kg GCSF, starting after each of the eight COJEC chemotherapy cycles and stopping 24 hours before the next cycle. Chemotherapy was administered every 10 days regardless of hematologic recovery, provided that infection was controlled.

Results

The PPGCSF arm had significantly fewer febrile neutropenic episodes (P = .002), days with fever (P = .004), hospital days (P = .017), and antibiotic days (P = .001). Reported Common Toxicity Criteria (CTC) graded toxicity was also significantly reduced: infections per cycle (P = .002), fever (P < .001), severe leucopenia (P < .001), neutropenia (P < .001), mucositis (P = .002), nausea/vomiting (P = .045), and constipation (P = .008). Severe weight loss was reduced significantly by 50% (P = .013). Protocol compliance with the rapid induction schedule was also significantly better in the PPGCSF arm shown by shorter time to completion (P = .005). PPGCSF did not adversely affect response rates or success of peripheral-blood stem-cell harvest.

Conclusion

Following these results, PPG-GSF was advised for all patients on rapid COJEC induction.

Prophylactic Granulocyte Colony-Stimulating Factor and Granulocyte-Macrophage Colony-Stimulating Factor Decrease Febrile Neutropenia After Chemotherapy in Children With Cancer: A Meta-Analysis of Randomized Controlled Trials

Purpose

To determine whether prophylactic hematopoietic colony-stimulating factors (CSFs) used in children with cancer reduce the rate of febrile neutropenia, hospitalization duration, documented infection rate, parenteral antibiotic duration, amphotericin B use, or infection-related mortality.

Methods

We included studies in this meta-analysis if their populations consisted of children, if there was randomization between CSFs and placebo or no therapy, if CSFs were administered prophylactically (before neutropenia or febrile neutropenia), and if chemotherapy treatments preceding CSFs and placebo or no therapy were identical. From 971 reviewed study articles, 16 were included.

Results

The mean rate of febrile neutropenia in the control arms was 57% (range, 39% to 100%). Using a random effects model, CSFs were associated with a reduction in febrile neutropenia, with a rate ratio of 0.80 (95% CI, 0.67 to 0.95; P = .01), and a decrease in hospitalization length, with a weighted mean difference of −1.9 days (95% CI, −2.7 to −1.1 days; P < .00001). CSF use was also associated with reduction in documented infections (rate ratio, 0.78; 95% CI, 0.62 to 0.97; P = .02) and reduction in amphotericin B use (rate ratio, 0.50; 95% CI, 0.28 to 0.87; P = .02). There was no difference in duration of parenteral antibiotic therapy (weighted mean difference, −4.3; 95% CI, −10.6 to 2.0 days; P = .2) or infection-related mortality (rate ratio, 1.02; 95% CI, 0.34 to 3.06; P = .97).

Conclusion

CSFs were associated with a 20% reduction in febrile neutropenia and shorter duration of hospitalization; however, CSFs did not reduce infection-related mortality.

Combined use of erythropoietin and granulocyte colony-stimulating factor does not decrease blood transfusion requirements during induction therapy for high-risk neuroblastoma: a randomized controlled trial

PURPOSE

To evaluate the efficacy of recombinant erythropoietin (EPO) and granulocyte colony-stimulating factor (G-CSF) in reducing blood transfusion requirements and stimulating hematopoiesis in children with high-risk neuroblastoma.

PATIENTS AND METHODS

Thirty-eight patients given six cycles of intensive induction chemotherapy for high-risk neuroblastoma were randomized to receive G-CSF (n = 20) or G-CSF + EPO (n = 18). Cytokines were given subcutaneously each day, starting 24 hours after each chemotherapy cycle and continuing until 48 hours before the start of the next cycle. The primary end point was the effect of EPO on total red cell transfusion requirements during induction therapy.

RESULTS

Patients who received G-CSF + EPO had a higher red cell transfusion requirement (median, 161.0 mL/kg) than did those who received G-CSF alone (median, 106.6 mL/kg; P =.005). In addition, among patients given transfusions for hemoglobin < or = 8 g/dL, those in the G-CSF + EPO group received more red cell transfusions than did those given G-CSF alone (median per patient, 10 v 8, respectively; P =.044). The two treatment groups had similar cumulative durations of neutropenia, incidences of febrile neutropenia, platelet transfusion requirements, and numbers of platelet transfusions; they also received induction chemotherapy for similar durations and had similar probabilities of progression-free survival and overall survival.

CONCLUSION

The addition of EPO to the G-CSF regimen provides no benefit for patients receiving intensive induction chemotherapy for high-risk neuroblastoma.