Effectiveness of daily versus non-daily granulocyte colony-stimulating factors in patients with solid tumours undergoing chemotherapy: a multivariate analysis of data from current practice

Evaluating the safety and effectiveness of PegaGen® (pegfilgrastim) for the prevention of chemotherapy-induced febrile neutropenia: a post-marketing surveillance study

PURPOSE

Phase IV clinical trials are required to evaluate the real-world safety and effectiveness of drugs. This study aimed to evaluate the safety and effectiveness of once-per-cycle administration of PegaGen^® (pegfilgrastim, CinnaGen, Iran) in cancer patients.

METHODS

In this open-label, multicenter, prospective, real-world, post-marketing surveillance study, patients with any type of cancer receiving chemotherapy regimens with a high risk of febrile neutropenia (FN) were included if they were prescribed pegfilgrastim for FN prophylaxis. The primary objective of this study was to assess the safety and the secondary objective was to assess the effectiveness of pegfilgrastim in the prevention of FN in cancer patients.

RESULTS

A total of 654 patients (51.73 ± 15.12 years of age) were enrolled and 3615 cycles of pegfilgrastim injections were recorded. The most common malignancies among the study patients were breast cancer (n = 192, 29.36%), lymphoma (n = 131, 20.03%), and gastric cancer (n = 65, 9.94%). The median (Q1, Q3) number of pegfilgrastim cycles per patient was 6 (4, 7). A single 6 mg dose was injected in 99.17% of the cycles. A total number of 816 adverse events (AEs) were reported in 246 patients (37.62%). Bone pain was recorded in 141 patients (21.56%) and in 440 cycles (12.17%). Among all patients, 45 patients (6.88%) experienced FN 51 times, and FN frequency was 1.4% among cycles. Moreover, 14 (2.14%) patients were hospitalized following FN. Antibiotics were administered to 24 patients (3.67%) for FN treatment.

CONCLUSION

The results from this post-marketing surveillance study support the safety and effectiveness of PegaGen^® used for the prevention of chemotherapy-induced FN in patients with various types of cancer and treatment regimens.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT04460079.

Efficacy and Safety for the Use of Half-Dosed Pegylated Granulocyte Colony-Stimulating Factors in Preventing Febrile Neutropenia During Chemotherapy in Patients With Malignant Tumors: A Multicenter, Open-Labeled, Single-Arm Phase 2 Trial

Background

Prophylactic granulocyte-colony stimulating factor (G-CSF) has been shown to effectively prevent febrile neutropenia (FN) and grade 3/4 neutropenia during myelosuppressive treatment. The present study reports the clinical efficacy and safety of the prophylactic use of G-CSF with a half dose for cancer patients with an intermediate risk of FN combined with ≥1 patient-specific risk during multiple chemotherapy.

Methods

This multicenter, one-arm, and open-label clinical study involved 151 patients [median age, 54 years old (range, 46.0–62.5); 38.4% female] with malignant tumors, including >20 different cancers. These patients underwent a total of 604 cycles of chemotherapy and received a half dose of PEG-rhG-CSF administration prior to each cycle.

Results

The incidence rate of FN was 3.3% for this cohort during chemotherapy. Chemotherapy delay occurred in 6 (4.0%) patients for 12 (2.0%) cycles. Early termination of cancer treatment occurred in 14 (9.3%) patients. In this cohort, 23 (15.2%) patients required antibiotic use during courses of chemotherapy. A total of 28 (18.5%) patients experienced clear adverse effects during cancer treatment.

Conclusion

The prophylactic PEG-rhG-CSF with a half dose can both efficaciously and safely prevent neutropenia for patients of diverse cancers with an intermediate risk of FN combined with ≥1 patient-specific risk during chemotherapy.

Real-world cost-effectiveness of primary prophylaxis with G-CSF biosimilars in patients at intermediate/high risk of febrile neutropenia

Background: Real-world data suggests superiority of pegfilgrastim (PEG) over filgrastim (FIL) in reducing the incidence of chemotherapy-induced febrile neutropenia (FN), probably attributable to underdosed FIL in practice. We used real-world data to assess the cost-effectiveness of primary prophylaxis with PEG versus FIL in cancer patients at intermediate-to-high risk of FN from a US payer perspective. Methods: A Markov model with lifetime horizon. Results: For the high-risk group, PEG (vs FIL) biosimilars resulted in 0.43 FN events prevented (FNp), 0.27 quality-adjusted life-years gained (QALYg) and a cost saving of USD$5703. For the intermediate-risk group, PEG biosimilar led to 0.18 FNp and 0.12 QALYg, at USD$9674/FNp and USD$14,502/QALYg. Conclusion: PEG biosimilars may provide opportunities to optimize FN management in patients with intermediate-to-high FN risk.

Supportive therapies in the prevention of chemotherapy-induced febrile neutropenia and appropriate use of granulocyte colony-stimulating factors: a Delphi consensus statement

PURPOSE

Data indicate that the use of prophylactic granulocyte colony-stimulating factors (G-CSFs) for chemotherapy-induced febrile neutropenia (FN) in routine practice is not consistent with guideline recommendations. The initiative "supportive care for febrile neutropenia prevention and appropriateness of G-CFS use" was undertaken to address the issue of inappropriate prescription of G-CSFs and to improve guideline adherence in the treatment of FN.

METHODS

In a two-round Delphi procedure, 36 medical oncologists reviewed clinically relevant recommendations on risk assessment, the appropriate use of G-CSFs, and the prevention of FN based on available literature and individual clinical expertise.

RESULTS

The consensus was reached on 16 out of 38 recommendations, which are backed by evidence from randomised clinical trials and routine clinical practice. The medical oncologists agreed that the severity of neutropenia depends on patients' characteristics and chemotherapy intensity, and therefore, the risk of severe neutropenia or FN should be assessed at each chemotherapy cycle so as to initiate prophylaxis with G-CSFs if required. The use of biosimilar G-CSFs, with similar efficacy and safety profiles to the originator biologic, has improved the availability and sustainability of cancer care. The timing of supportive therapy is crucial; for example, long-acting G-CSF should be administered 24-72 h after chemotherapy administration. Each biological agent has a recommended administration dose and duration, and it is important to follow these recommendations to avoid complications associated with under-prophylaxis.

CONCLUSION

It is hoped that these statements will help to increase adherence to guideline recommendations for appropriate G-CSF use and improve patient care.

Efficacy and Safety of Filgrastim and Its Biosimilars to Prevent Febrile Neutropenia in Cancer Patients: A Prospective Study and Meta-Analysis

Simple Summary

Febrile neutropenia is the serious side-effect associated with myelosuppressive chemotherapy. Filgrastim, the first granulocyte colony-stimulating factor (G-CSF) was approved by the Food and Drug Administration for the treatment of neutropenia. Subsequently, pegfilgrastim (long-acting G-CSF) and filgrastim biosimilars were developed to have comparable efficacy to filgrastim. Therefore, it is necessary to produce a systematic review and meta-analysis that provides evidence that filgrastim is more efficacious than placebo/no-treatment, as it provides evidence on the comparable efficacy of filgrastim versus pegfilgrastim and biosimilar filgrastim.

Abstract

Background: The aim of this review and meta-analysis was to identify, assess, meta-analyze and summarize the comparative effectiveness and safety of filgrastim in head-to-head trials with placebo/no treatment, pegfilgrastim (and biosimilar filgrastim to update advances in the field. Methods: The preferred reporting items for systematic reviews and meta-analyses PRISMA statement were applied, and a random-effect model was used. Primary endpoints were the rate and duration of grade 3 or 4 neutropenia, and an incidence rate of febrile neutropenia. Secondary endpoints were time to absolute neutrophil count ANC recovery, depth of ANC nadir (lowest ANC), neutropenia-related hospitalization and other neutropenia-related complications. For filgrastim versus biosimilar filgrastim comparison, the primary efficacy endpoint was the mean difference in duration of severe neutropenia DSN. Results: A total of 56 studies were considered that included data from 13,058 cancer patients. The risk of febrile neutropenia in filgrastim versus placebo/no treatment was not statistically different. The risk ratio for febrile neutropenia was 0.58, a 42% reduction in favor of filgrastim. The most reported adverse event with FIL was bone pain. For pegfilgrastim versus filgrastim, no statistically significant difference was noted. The risk ratio was 0.90 (95% CI 0.67 to 1.12). The overall difference in duration of severe neutropenia between filgrastim and biosimilar filgrastim was not statistically significant. The risk ratio was 1.03 (95% CI 0.93 to 1.13). Conclusions: Filgrastim was effective and safe in reducing febrile neutropenia and related complications, compared to placebo/no treatment. No notable differences were found between pegfilgrastim and filgrastim in terms of efficacy and safety. However, a similar efficacy profile was observed with FIL and its biosimilars.

Prophylaxis and treatment strategies for optimizing chemotherapy relative dose intensity

INTRODUCTION

A decrease in relative-dose intensity (RDI) of chemotherapy has been shown to be associated with poor patient outcomes in solid tumors and non-Hodgkin's lymphoma. The actual delivered chemotherapy dose received by patients can be influenced by dose reductions and treatment delays, often due to toxicities, most commonly chemotherapy-induced neutropenia (CIN).

AREAS COVERED

We review seminal evidence and more recent studies that have shown an association between higher RDI and improved patient survival. A smaller number of studies has shown no association between RDI and outcomes. These differences may be due to study limitations, including low power, differences in patient and disease characteristics, or the chemotherapeutic regimen. We describe guidelines recommendations to prevent and treat CIN with granulocyte-colony stimulating factor (G-CSF) and describe novel approaches to prevent neutropenia that are being developed that may provide greater value and be associated with fewer adverse events than standard G-CSF options.

EXPERT OPINION

Maintaining RDI is important to ensure optimal patient outcomes. This can be achieved through the proper administration of G-CSF prophylaxis and treatment. Newer agents in development to treat and/or prevent CIN are entering regulatory review and may potentially change the treatment landscape for CIN in the future.

Pooled Analysis on the Effectiveness and Safety of Lipegfilgrastim in Patients With Urological Malignancies in the Real-World Setting

Lipegfilgrastim is a long-acting glycopegylated granulocyte-colony stimulating factor (G-CSF) approved for the management of chemotherapy-induced neutropenia. In general, there is little information on the use of any G-CSFs specifically in patients with urological malignancies receiving chemotherapy. This report combines information from two prospective non-interventional studies on the prophylactic use of lipegfilgrastim in urological cancer patients receiving chemotherapy in the real-world setting. Data were derived from two phase IV studies (NADIR and LEOS) with similar protocols conducted in nine European countries. Analysis included 228 patients (142 prostate, 50 testicular, 27 bladder, and 9 other urological cancers). Chemotherapy-induced febrile neutropenia risk was classified as high (43.0%), intermediate (49.1%), or low (7.5%). Lipegfilgrastim was administered as primary (n=180, 78.9%) or secondary (n=29, 12.7%) prophylaxis. The incidence of febrile neutropenia over all chemotherapy cycles (n=998) and first cycles (n=228) for which lipegfilgrastim was administered for prophylaxis was 2.6% and 1.3%, respectively. Corresponding results for Grade 3/4 neutropenia were 2.2% and 0.9%, respectively. Adverse drug reactions occurred in 24 patients (10.5%): those in more than one patient were bone pain (n=6, 2.6%) and pyrexia (n=3, 1.3%). The use of lipegfilgrastim for the prophylaxis of chemotherapy-induced neutropenia was effective and well tolerated in patients with urological malignancies in the real-world setting.

Pegteograstim prophylaxis for chemotherapy-induced neutropenia and febrile neutropenia: a prospective, observational, postmarketing surveillance study in Korea

PURPOSE

This observational study aimed to evaluate the safety and efficacy of pegteograstim prophylaxis in patients with lymphoma and solid malignancies.

METHODS

This study was conducted at 18 sites in Korea between November 2015 and August 2018.

RESULTS

In total, 611 patients (female, 61.2%) with a median age of 58 (range, 18-88) years were included. Most patients had lymphomas (n = 371, 60.7%) and breast cancer (n = 230, 37.6%) and were administered R-CHOP21 (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone per 21 days) (n = 284, 46.5%) and AC (doxorubicin and cyclophosphamide) (n = 177, 29.0%). The total pegteograstim dose in the 611 patients was 14,970 mg (2495 doses), with each patient receiving an average daily dose of 6.0 mg. Neutropenia grade 4 occurred in 97 patients (15.9%), and febrile neutropenia (FN) occurred in 31 patients (5.1%). Among the 611 patients, 267 patients (43.7%) developed 882 adverse events (AEs), and 11 patients (1.8%) experienced 18 adverse drug reactions (ADRs). There were 62 patients (10.2%) who experienced 81 cases of serious adverse events (SAEs), with FN and pneumonia being the most frequent at 14 and 13 episodes, respectively, in 13 patients (2.1%). Meanwhile, 1 patient (0.2%) developed 2 episodes of serious ADRs (grade 1 and grade 2 hypotension). No safety concerns in the elderly and patients with liver and/or renal disease were identified.

CONCLUSION

The prophylactic use of pegteograstim might have good overall safety and efficacy in patients with lymphomas and solid malignancies in routine clinical practice, even in those who are elderly and have liver and renal diseases.

Biosimilar Pegfilgrastim: Improving Access and Optimising Practice to Supportive Care that Enables Cure

Febrile neutropenia (FN) is a serious complication of chemotherapy, which can cause significant morbidity and mortality, result in dose delays and reductions and, ultimately, reduce cancer survival. Over the past decade, the availability of biosimilar filgrastim (short-acting granulocyte colony-stimulating factor [G-CSF]) has transformed patient access, with clear evidence of clinical benefit at preventing FN at reduced costs. In 2019, seven biosimilar pegfilgrastims (long-acting G-CSFs) were licensed, creating optimal market conditions and choice for prescribers. FN affects up to 117 per 1000 cancer patients, with mortality rates in the range of 2–21%. By reducing FN incidence and improving chemotherapy relative dose intensity (RDI), G-CSF has been associated with a 3.2% absolute survival benefit. Guidelines recommend primary prophylaxis and that filgrastim be administered for 10–14 days, while pegfilgrastim is administered once per cycle. When taken according to the guidelines, pegfilgrastim and filgrastim are equally effective. However, in routine clinical practice, filgrastim is often under-dosed (< 7 days) and has been shown to be inferior to pegfilgrastim at reducing FN incidence, hospitalisations and maintaining RDI. Once-per-cycle administration with pegfilgrastim might also aid patient adherence. The introduction of biosimilar pegfilgrastim should instigate a rethink of neutropenia management. Biosimilar pegfilgrastim offers countries using biosimilar filgrastim opportunities to improve adherence and thus cancer survival, whilst offering economic benefits for countries using reference pegfilgrastim. These benefits can be realised in full if biosimilar pegfilgrastim becomes part of routine clinical practice supported by drug and therapeutic committees implementing guidelines with multidisciplinary support in the hospital.

Safety and tolerability of Peg-grafeel™, a pegfilgrastim, for the prophylactic treatment of chemotherapy-induced neutropenia and febrile neutropenia: A prospective, observational, postmarketing surveillance study in India

BACKGROUND

A granulocyte colony-stimulating factor, pegfilgrastim, is efficacious though expensive for prophylactic treatment of chemotherapy-induced neutropenia and febrile neutropenia. Biologics available and accessible today, having acceptable safety-efficacy profiles, require postapproval studies for better understanding of such drugs in clinical settings.

AIM

This postmarketing surveillance study evaluated the safety of prophylactic Peg-grafeel^™ (pegfilgrastim) in cancer patients with chemotherapy-induced neutropenia.

SETTINGS AND DESIGN

This prospective, noninterventional, single-arm, open-label study was conducted at 10 study sites in India.

METHODS

Patients received subcutaneous 6 mg Peg-grafeel^™ approximately 24 h following chemotherapy as part of routine patient care.

STATISTICAL ANALYSIS

Data were summarized descriptively.

RESULTS

The study included 250 patients (male: female = 36.4%:63.6%; median age, 54 [16-80] years). Most patients had Stage III (33.2%) or IV (41.6%) cancers and received cyclophosphamide (37.2%) and doxorubicin (31.6%) as chemotherapy. On an average, 4 Peg-grafeel^™ doses were administered per patient. Treatment-emergent adverse events (AEs) were reported in 115 (46%) patients, the most common being vomiting (11.6%), pain (11.2%), nausea (8.4%), and constipation (8.4%). Peg-grafeel^™-related AEs included pain (3.2%), asthenia (2.4%), and arthralgia (1.2%). Bone pain (0.4%) and extremity pain (1.2%) were rare. Grade 3/4 neutropenia and febrile neutropenia occurred in 4 (1.6%) and 3 (1.2%) patients, respectively. Serious AEs included vomiting (2.8%) and pyrexia (2%). No new safety concerns were identified. None of the five deaths was considered related to Peg-grafeel^™.

CONCLUSION

The overall safety profile of Peg-grafeel^™ was consistent with the expected safety profile of pegfilgrastim in patients with advanced malignancies in a clinical setting.

Introduction of biosimilar pegfilgrastim in France: Economic analysis of switching from originator

Objectives

To assess the economic impact of introducing biosimilar pegfilgrastim compared to the current standard granulocyte colony-stimulating factor (G-CSF) practice in France.

Methods

A budget impact model was developed to investigate the impact of introducing pegfilgrastim biosimilar over 5 years. The model analysed drug acquisition costs, ambulatory costs, as well as costs associated with poor outcomes, and compared the current standard practice of long-acting and short-acting G-CSF to a revised practice including pegfilgrastim biosimilar in addition to standard practice treatments. The cost of switching to pegfilgrastim biosimilar, within a pharmacy setting, was analysed within the model using data from a survey of French pharmacists.

Results

The budget impact model calculated a cost saving of €51,007,531 over 5 years switching from the current standard practice to pegfilgrastim biosimilar. A sensitivity analysis accounting for variation in pegfilgrastim biosimilar uptake of 1) 15% in year 1 and 1% in years 2–5 and 2) 15% in years 1–5, estimated savings ranging between €29,377,784 and €79,847,194, respectively. A further analysis predicted cost savings of €287,344,835 over 5 years with the extension of pegfilgrastim biosimilar, at an uptake of 15% in year 1 and 7% in years 2–4, to both long-acting and short-acting G-CSF groups compared to unchanged current practice.

Conclusions

The introduction of pegfilgrastim biosimilar will help to reduce cost and alleviate some of the financial pressure on the French healthcare system.

Impact of granulocyte colony-stimulating factor on FOLFIRINOX-induced neutropenia prevention: A population pharmacokinetic/pharmacodynamic approach

AIMS

Granulocyte colony-stimulating factor (G-CSF) is frequently prescribed to prevent chemotherapy-induced neutropenia, but the administration schedule remains empirical in case of bimonthly chemotherapy such as FOLFIRINOX regimen. This pharmacokinetic/pharmacodynamic (PK/PD) study was performed to determine the effect of different G-CSF regimens on the incidence and duration of neutropenia following FOLFIRINOX administration in order to propose an optimal G-CSF dosing schedule.

METHODS

A population PK/PD model was developed to describe individual neutrophil time course from absolute neutrophil counts (ANC) obtained in 40 advanced cancer patients receiving FOLFIRINOX regimen. The structural model considered ANC dynamics, neutropenic effect of cytotoxics and the stimulating effect of G-CSF on neutrophils. Final model estimates were used to simulate different G-CSF dosing schedules for 1000 virtual subjects. The incidence and duration of neutropenia were then calculated for different G-CSF dosing schedules.

RESULTS

The final model successfully described the myelosuppressive effect induced by the 3 cytotoxics for all patients. Simulations showed that pegfilgrastim administration reduced the risk of severe neutropenia by 22.9% for subjects with low ANC at the start of chemotherapy. Median duration in this group was also shortened by 3.1 days when compared to absence of G-CSF. Delayed G-CSF administration was responsible for higher incidence and longer duration of neutropenia compared to absence of administration.

CONCLUSION

The PK/PD model well described our population's ANC data. Simulations showed that pegylated-G-CSF administration 24 hours after the end of chemotherapy seems to be the optimal schedule to reduce FOLFIRINOX-induced neutropenia. We also underline the potential negative effect of G-CSF maladministration.

A Phase 2, International, Multicenter, Open-label Clinical Trial of Subcutaneous Tbo-Filgrastim in Pediatric Patients With Solid Tumors Undergoing Myelosuppressive Chemotherapy

This phase 2, multicenter, open-label trial investigated the safety and tolerability of tbo-filgrastim in pediatric patients receiving myelosuppressive chemotherapy. In total, 50 patients 1 month to below 16 years of age with solid tumors without bone marrow involvement were stratified into 3 age groups (2 infants, 30 children, 18 adolescents) and prophylactically administered tbo-filgrastim 5 µg/kg body weight once daily subcutaneously. The administration started after the last chemotherapy treatment in week 1 of the first cycle and continued until the expected neutrophil nadir had passed, and the neutrophil count had recovered to 2.0×10/L. The primary endpoint was safety and tolerability of tbo-filgrastim; secondary endpoints included efficacy. The mean (SD) number of doses administered was 9.2 (2.83) in children and 7.3 (1.88) in adolescents. Serious treatment-emergent adverse events were reported in 24% of patients; the most common were febrile neutropenia (FN) (12%), anemia (8%), and thrombocytopenia (8%). Nine patients (18%) experienced mild treatment-related treatment-emergent adverse events; the most common were musculoskeletal and connective tissue disorders (8%). No deaths or withdrawals occurred. The incidence of severe neutropenia (SN) was 52% and the mean (SD) duration of SN was 1.8 (2.21) days; FN incidence was 26%. A daily dose of tbo-filgrastim 5 μg/kg body weight administered to pediatric patients demonstrated a safety profile consistent with the safety profile in adult patients. The incidence of FN was on the lower end of the range reported in the literature and the SN results provide supportive data on the efficacy of tbo-filgrastim in pediatric patients.

Patient-Administered Biologic and Biosimilar Filgrastim May Offer More Affordable Options for Patients with Nonmyeloid Malignancies Receiving Chemotherapy in the United States: A Budget Impact Analysis from the Payer Perspective

BACKGROUND

Granulocyte colony-stimulating factors (G-CSFs) are often administered to reduce the incidence, severity, and duration of febrile neutropenia (FN) in chemotherapy patients. Tbo-filgrastim and filgrastim-sndz represent a follow-on biologic and a biosimilar version, respectively, of the short-acting G-CSF filgrastim with comparable efficacy and safety.

OBJECTIVE

To estimate the budget impact of increasing use of patient-(home-) administered tbo-filgrastim and filgrastim-sndz from a U.S. payer perspective.

METHODS

An interactive budget impact model was developed to estimate the changes in drug cost associated with projected increases in the market share of tbo-filgrastim from 5% to 10% and of filgrastim-sndz from 10% to 12% (with a corresponding decrease in filgrastim market share from 85% to 78%) for a 1 million-member health plan among patients with nonmyeloid malignancies receiving chemotherapy with a high risk of FN. Patient self-administration at home was assumed for 20% of patients receiving short-acting G-CSF treatment; all products were purchased through the patient's pharmacy benefit and were assumed to have tier 3 formulary status with a patient copay of $54 per prescription. Base-case data were derived from publicly available resources. The total plan budget impact was calculated using a 1-year time horizon, along with the differences in per member per month and per member per year (PMPY) costs between the current and future scenarios.

RESULTS

The effective annual per-patient drug cost to the plan totaled between $16,961 and $27,199, depending on dosage and packaging, for tbo-filgrastim; between $16,216 and $26,015 for filgrastim-sndz; and between $19,134 and $30,663 for filgrastim. The estimated total annual plan cost associated with patient-administered short-acting G-CSFs was $53,298,217 (PMPY = $53.30) in the current scenario and $52,828,832 (PMPY = $52.82) in the future scenario. Cost savings totaled $469,385 (PMPY = $0.48). The model was most sensitive to changes in the percentage of patients self-administering G-CSF at home and to the wholesale acquisition cost for filgrastim.

CONCLUSIONS

The effective annual plan per-patient drug costs for tbo-filgrastim and filgrastim-sndz were 11% and 15% lower than filgrastim, respectively. The present analysis estimated an annual U.S. health plan cost savings approaching $0.5 million following increases in market shares of approximately 5% for tbo-filgrastim and 2% for filgrastim-sndz.

DISCLOSURES

This study was sponsored by Teva Branded Pharmaceutical Products R & D, which participated in the study design, data interpretation and analysis, the writing of the report, and the decision to submit. Aventine Consulting received consulting fees from Teva Pharmaceuticals and developed the cost model and provided data analysis support. Trautman and James are employed by Aventine Consulting. Szabo and Tang are employed by Teva Pharmaceuticals.

Systematic Review and Meta-analysis of Short- versus Long-Acting Granulocyte Colony-Stimulating Factors for Reduction of Chemotherapy-Induced Febrile Neutropenia

Introduction

Short- and long-acting granulocyte-colony stimulating factors (G-CSFs) are approved for the reduction of febrile neutropenia. A systematic literature review was performed to identify randomized controlled trials (RCTs) and non-RCTs reporting the use of G-CSFs following chemotherapy treatment.

Methods

Medline^®/Medline in-process, Embase^®, and the Cochrane Library were searched for studies published between January 2003 and June 2016. A hand-search of relevant conference proceedings was conducted for meetings held between 2012 and 2016. Eligible studies were restricted to those reporting a direct, head-to-head comparison of short- versus long-acting G-CSFs for reduction of chemotherapy-induced febrile neutropenia. Risk-of-bias assessments were performed for full publications only.

Results

The search strategy yielded 4044 articles for electronic screening. Thirty-six publications were evaluated for the meta-analysis: 11 of 12 RCTs and 2 of 24 non-RCTs administered doses of the short-acting G-CSF filgrastim for ≥ 7 days. In RCT studies, there was no statistically significant difference in outcomes of interest between short- and long-acting G-CSFs. In non-RCTs, the overall risk was lower with long-acting G-CSF than with short-acting G-CSF for incidence of febrile neutropenia [overall relative risk (RR) = 0.67, P  = 0.023], hospitalizations (overall RR = 0.68, P  < 0.05), and chemotherapy dose delays (overall RR = 0.68, P  = 0.020).

Conclusions

Overall, the weight of evidence from RCTs indicates little difference in efficacy between the short- and long-acting G-CSFs if dosed according to recommended guidelines. There is some evidence for greater efficacy for long-acting G-CSFs in non-RCTs, which may be a result of under-dosing of short-acting G-CSFs in general practice in real-world usage.

Funding

Hospira Inc, which was acquired by Pfizer Inc in September 2015, and Pfizer Inc.

Electronic supplementary material

The online version of this article (10.1007/s12325-018-0798-6) contains supplementary material, which is available to authorized users.

Reduced dose pegfilgrastim is associated with less bone pain without increased neutropenia: a retrospective study

BACKGROUND

Chemotherapy for breast cancer is associated with a high risk of neutropenia. Pegfilgrastim reduces the risk of neutropenic fever but commonly causes bone pain.

OBJECTIVE

Evaluate whether a reduced dose of pegfilgrastim (3 mg) reduced the frequency of bone pain without compromising efficacy.

METHODS

Records reviewed from breast cancer patients who received at least one 3 mg dose of pegfilgrastim, white blood count (WBC), and absolute granulocyte counts (AGC) were collected. Musculoskeletal pain scale was collected at each visit.

RESULTS

265 treatments from 36 women were analyzed. There was no difference in post-treatment AGC between 3 versus 6 mg. Leukocytosis (WBC > 20,000 cells/cu mm) was more likely for those treated with 6 mg (chi-square 5.265, p = 0.0215). There was higher change in bone pain in patients who received 6 mg doses compared to none or 3 mg.

LIMITATIONS

In this retrospective, non-randomized study, we found the majority of patients received the reduced 3 mg dose after intolerance to the 6 mg dose. It is unknown if smaller or larger doses than 3 mg would achieve similar results or whether 3 mg dose would be effective as an initial therapy or for patients receiving different chemotherapy regimens. Pain is observed despite premedication with naproxen and/or loratidine.

CONCLUSION

Reduced dose of pegfilgrastim 3 mg was less likely to cause bone pain. The reduced dose was not associated with a significant difference in post-treatment AGC or rate of serious infection.

Pooled analysis of two randomized, double-blind trials comparing proposed biosimilar LA-EP2006 with reference pegfilgrastim in breast cancer

Background

Following the functional and physicochemical characterization of a proposed biosimilar, comparative clinical studies help to confirm biosimilarity by demonstrating similar safety and efficacy to the reference product in a sensitive patient population.

Patients and methods

LA-EP2006 is a proposed biosimilar that has been developed for pegfilgrastim, a long-acting form of granulocyte colony-stimulating factor for the prevention of neutropenia. The current analysis reports data pooled from two independent, multinational, prospective, randomized, controlled, double-blind phase III studies of similar design comparing the safety and efficacy of reference pegfilgrastim with LA-EP2006 in patients with breast cancer receiving myelotoxic (neo)adjuvant TAC (docetaxel, doxorubicin, and cyclophosphamide) chemotherapy and requiring granulocyte colony-stimulating factor.

Results

A total of 624 patients were randomized in the PROTECT-1 and PROTECT-2 studies (NCT01735175; NCT01516736) (LA-EP2006: n = 314; reference: n = 310). Baseline characteristics of patients were well balanced across treatment groups. The primary end point, mean duration of severe neutropenia in the first chemotherapy cycle was similar in both the LA-EP2006 and reference groups (1.05 ± 1.055 days versus 1.01 ± 0.958 days), with a treatment difference of - 0.04 days [95% confidence interval (CI): -0.19 to 0.11] that met the equivalence criteria (the 95% CI were within the defined margin of ±1 day). Secondary end points, such as the nadir of absolute neutrophil count and the incidence of febrile neutropenia, were also similar between LA-EP2006 and reference pegfilgrastim. The safety and tolerability profile of LA-EP2006 was similar to that observed with reference pegfilgrastim, and there were no reports of neutralizing antibodies.

Conclusions

This pooled analysis confirms, as a part of totality of evidence approach, that the proposed biosimilar pegfilgrastim LA-EP2006 has a comparable efficacy and safety profile to reference pegfilgrastim in patients with breast cancer receiving TAC chemotherapy.

Clinical trial numbers

NCT01735175 and NCT01516736.

The Impact of Biosimilars in Supportive Care in Cancer

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Adequate Neutrophil Responses and Non-Inferior Clinical Outcomes Can Be Achieved by a Two-Day Course of Low-Dose Filgrastim: A Retrospective Single Institution Experience

Background

Filgrastim is used in the setting of chemotherapy-induced neutropenia to stimulate recovery of bone marrow, which allows for further chemotherapy administration without delay. The recommended dose is 5 ug/kg. The commercially available vials of the drug come in two strengths; 300 ug and 480 ug. Due to these limitations in dosage formulations, it is a frequent occurrence to administer a lower dosage to patients weighing more than 60 kg, in whom the ideal dose would have been more than 300 ug but less than 480 ug. It is also a frequent practice to administer the drug for two consecutive days as it often leads to adequate response that will render patients eligible for their next cycle administration.

Objective

To determine whether a course of 300 ug of filgrastim administered daily for two consecutive days was as successful at reducing chemotherapy-induced neutropenia-related complications in patients with a higher weight (>60 kg) and hence receiving suboptimal dose as compared to those with weight less than 60 kg who are receiving the recommended dose.

Methods

We identified 91 patients from our facility with chemotherapy-induced neutropenia treated with 300 ug of filgrastim daily for two consecutive days, and we separated them into low, medium, and high weight groups. Multivariate logistic regression models examined correlations between outcomes (e.g., increases in absolute neutrophil count) and predictors (e.g., weight groups).

Results

The vast majority of encounters demonstrated rises in white blood cell (WBC) and absolute neutrophil count (ANC). Infection rates were not significantly different between low and medium weight groups (5% vs 0%; p = 0.1658), but the high weight group’s infection rate was significantly higher than the medium weight group (5% vs 33%; p = 0.001). The high weight group did have an increased rate of febrile neutropenia as compared to medium and low weight groups, but these differences were not significant. Incidences of chemotherapy delay and dose reduction were comparable across the three weight groups.

Limitations

Retrospective study, small sample size, heterogeneous cancer sites and different chemotherapy regimens administered limit generalizability of findings.

Conclusion

Patients with weights <85 kg receiving a two-day course of 300 ug of filgrastim have similar neutropenia-related complication rates with a potential percent cost-savings of roughly 43%.

Hospitalizations, outcomes, and management costs of febrile neutropenia in patients from a managed care population

PURPOSE

The study objective was to evaluate chemotherapy treatment patterns and incidence, cost, and resource utilization of febrile neutropenia-related hospitalization (FNH) in patients with breast cancer, lung cancer, and non-Hodgkin's lymphoma (NHL) from Kaiser Permanente Southern California (KPSC), a large integrated delivery system.

METHODS

Adults ≥18 years with any stage breast cancer, lung cancer, or NHL who initiated myelosuppressive chemotherapy from 01/01/2006 to 12/31/2009 were included. Chemotherapy dose delays ≥7 days, relative dose intensity (RDI), regimen switching, FNH and all-cause mortality, granulocyte colony-stimulating factor (G-CSF) and antibiotic use, and healthcare utilization/cost were evaluated by cancer type, regimen, and/or cycle.

RESULTS

Among 3314 breast cancer patients, 25.3% received an RDI ≤85%, 13.9% experienced FNH with an all-cause mortality rate of 2.0%, and 20.2% received primary prophylaxis with G-CSF. Among those with FNH, mean hospital length of stay (LOS) was 4.1 days, and mean total costs were $20,462. Among 1443 lung cancer patients, 17.9% had an RDI ≤85%, 8.0% experienced FNH with an all-cause mortality rate of 25.2%, and 4.5% received primary prophylaxis with G-CSF. Among those with FNH, mean LOS was 6.8 days, and mean total costs were $32,964. Among 581 NHL patients, 27.9% had an RDI ≤85% and 22.4% experienced FNH with an all-cause mortality rate of 13%. Among those with FNH, mean LOS was 7.9 days, and mean total costs were $37,555.

CONCLUSIONS

Marked variability was observed among different cancer types and chemotherapy regimens. Given the variability, detailed insight into incidence, management, and burden of FN can help inform clinical decision making.

Refining the role of pegfilgrastim (a long-acting G-CSF) for prevention of chemotherapy-induced febrile neutropenia: consensus guidance recommendations

Purpose

Chemotherapy-induced febrile neutropenia (FN) causes treatment delays and interruptions and can have fatal consequences. Current guidelines provide recommendations on granulocyte colony-stimulating factors (G-CSF) for prevention of FN, but guidance is unclear regarding use of short- vs long-acting G-CSF (e.g., filgrastim vs pegfilgrastim/lipegfilgrastim, respectively). An international panel of experts convened to develop guidance on appropriate use of pegfilgrastim for prevention of chemotherapy-induced FN.

Methods

Guidance recommendations were developed following a literature review, survey, evaluation of current practice, and an expert meeting. Consensus was established using an anonymous Delphi-based approach.

Results

Guidance recommendations for prevention of treatment-associated FN were as follows: for treatment with curative intent, maintenance of dose intensity using G-CSF to prevent dose delays/reduction should be standard of care; for treatment-associated FN risk ≥ 20%, short-acting G-CSF/pegfilgrastim should be given from cycle 1 onwards; and for treatment-associated FN risk < 20%, short-acting G-CSF/pegfilgrastim should be given if factors suggest overall risk (including treatment-related and patient-related risk factors) is ≥ 20%. It was agreed that pegfilgrastim and 11 days’ filgrastim have similar efficacy and safety and that pegfilgrastim is preferred to < 11 days’ filgrastim (and may be preferred to ≥ 11 days’ filgrastim based on adherence and convenience); pegfilgrastim is not appropriate in weekly chemotherapy; in split-dose chemotherapy, pegfilgrastim is recommended 24 h after last chemotherapy dose; and during palliative chemotherapy, patient adherence and convenience may favor pegfilgrastim.

Conclusion

In this era of targeted therapies, additional trials with G-CSF are still required. These recommendations should be used with existing guidelines to optimize pegfilgrastim use in clinical practice.

Meta-analysis and indirect treatment comparison of lipegfilgrastim with pegfilgrastim and filgrastim for the reduction of chemotherapy-induced neutropenia-related events

Background

Granulocyte colony-stimulating factors are effective at reducing the risk and duration of neutropenia. The current meta-analysis compared the neutropenia-related efficacy and safety of lipegfilgrastim to those of pegfilgrastim and filgrastim.

Methods

Embase was searched for trials examining the efficacy/safety of lipegfilgrastim, pegfilgrastim, or filgrastim. Outcomes included febrile neutropenia, severe neutropenia, duration of severe neutropenia, time to recovery of absolute neutrophil count, and incidence of bone pain. Direct comparisons were made using random-effects models. No trials directly compared lipegfilgrastim and filgrastim. Indirect comparisons were made between lipegfilgrastim and filgrastim with pegfilgrastim as the common comparator.

Results

This meta-analysis included a total of 5769 patients from 24 studies. Over all cycles, lipegfilgrastim showed a lower, nonsignificant risk of febrile neutropenia compared with pegfilgrastim. Lipegfilgrastim has a lower risk of febrile neutropenia versus filgrastim but was also not statistically significant. The risk ratio for severe neutropenia in cycle 1 was 0.80, a 20% reduction in favor of lipegfilgrastim. For cycles 2–4, the risk ratio was 0.53 (0.35, 0.79) for lipegfilgrastim versus pegfilgrastim. The risk of severe neutropenia in cycles 2–4 was also significantly lower for lipegfilgrastim (risk ratio 0.45, 0.27, 0.75, respectively). No significant differences were found for febrile neutropenia and severe neutropenia in cycle 1. However, in cycles 2–4, lipegfilgrastim was associated with significant and clinically meaningful reductions in risk of severe neutropenia versus either pegfilgrastim or filgrastim.

Conclusions

Compared with pegfilgrastim or filgrastim, lipegfilgrastim has a statistically significantly lower absolute neutrophil count recovery time; however, differences in duration of severe neutropenia and bone pain were nonsignificant.

The Effectiveness of Febrile Neutropenia Prophylaxis with Lipegfilgrastim in Routine Clinical Practice

Febrile neutropenia (FN) is a common and potentially fatal complication of anticancer treatment, particularly in patients receiving myelosuppressive chemotherapy. It has been shown that prophylaxis with granulocyte colony-stimulating factor (G-CSF), especially its pegylated forms, significantly reduces the incidence of FN, the likelihood of chemotherapy dose intensity reduction and, also, the number of hospitalizations due to FN. This review discusses currently published results from clinical trials dealing with FN prophylaxis in routine clinical practice in patients with solid tumors and myeloproliferative malignancies with a focus on lipegfilgrastim, which is the newest modification of the original molecule filgrastim. The discussed results proved that prophylactic administration of lipegfilgrastim can almost eliminate the risk of FN and significantly reduce the risk of chemotherapy (CHT) dose reduction in routine clinical practice in cases of a clear high-risk chemotherapy regimen or in the presence of risk factors (such as age, comorbidities, performance status, etc.) in patients who received chemotherapy with medium risk of FN.

Comparative effectiveness of granulocyte colony-stimulating factors to prevent febrile neutropenia and related complications in cancer patients in clinical practice: A systematic review

Introduction

Febrile neutropenia (FN) is a serious side-effect of myelosuppressive chemotherapy. Several clinical trials and observational studies have evaluated the effects of prophylactic granulocyte colony-stimulating factors (G-CSFs) on risk of FN and related complications; however, no systematic reviews have focused on effectiveness in routine clinical practice. Here, we perform a systematic review assessing the comparative effectiveness of prophylaxis with a long-acting G-CSF (pegfilgrastim) versus short-acting G-CSFs (filgrastim, lenograstim, and filgrastim biosimilars) in cancer patients in real-world clinical settings.

Methods

A systematic review was performed based on a pre-specified protocol and was consistent with the Cochrane Collaboration Handbook (2009) and the Centre for Reviews and Dissemination’s Guidance for Undertaking Reviews in Health Care (2011). MEDLINE, Embase, BIOSIS, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Library databases were searched for articles published from January 2002 to June 2014. Congress databases (MASCC/ASCO/ESMO) and Google Scholar were searched for abstracts published from January 2012 to August 2014. Filgrastim (NEUPOGEN®), lenograstim and nivestim (a filgrastim biosimilar) were the only short-acting G-CSFs and pegfilgrastim (Neulasta®) was the only long-acting G-CSF described in eligible studies. Outcomes of interest were FN, FN-related hospitalisation and other FN-related complications (death, chemotherapy dose delays and reductions, antimicrobial treatment, severe neutropenia and costs and resource use).

Results

Of 1259 unique records identified, 18 real-world observational studies met predefined inclusion criteria; 15 were retrospective studies, and 3 were prospective studies. Multiple tumour types, chemotherapy regimens and geographical regions were included. Seven studies provided statistical comparisons of the risk of FN; risk of FN among patients receiving prophylaxis with pegfilgrastim versus short-acting G-CSF was significantly lower in three studies, numerically lower in three studies, and numerically higher in one study. Six studies provided statistical comparisons of the risk of FN-related hospitalisation; risk of FN-related hospitalisation among patients receiving prophylaxis with pegfilgrastim versus short-acting G-CSF was significantly lower in all six studies, though some variation was seen in subanalyses. Data for other outcomes were sparse with available results being generally consistent with the results seen for risk of FN and FN-related hospitalisation.

Conclusions

Based on the findings from this review of real-world comparative effectiveness studies, risks of FN and FN-related complications were generally lower for prophylaxis with pegfilgrastim versus prophylaxis with short-acting G-CSFs.

Results of a prospective dose intensity and neutropenia prophylaxis evaluation programme (DIEPP) in cancer patients at risk of febrile neutropenia due to myelosuppressive chemotherapy

OBJECTIVE

To describe the incidence of febrile neutropenia (FN) and use of pegfilgrastim in cancer patients with high overall risk of FN and to investigate the relationship between granulocyte-colony stimulating factor (G-CSF) guideline adherence and chemotherapy delivery in Central and Eastern Europe (CEE) and Austria.

METHODS

Dose Intensity Evaluation Program and Prophylaxis (DIEPP) was a multicentre, prospective, and observational study of adult patients with breast cancer, lymphoma, lung cancer, gastric cancer, and ovarian cancer, who received chemotherapy with pegfilgrastim support and who had an overall risk of FN ≥ 20 %. Physicians assessed patient risk factors and reported their reasons for administering pegfilgrastim.

RESULTS

Patients were enrolled from 113 centres in CEE and Austria between August 2010 and July 2013, and data were analysed from 1072 patients. The most common tumour types were breast cancer (50 %) and lymphoma (24 %). FN incidence was 5 % overall. FN occurred in 3 % of patients (28/875) who received pegfilgrastim as primary prophylaxis (PP) and 13 % of patients (19/142) who received it as secondary prophylaxis (SP); 79 % of FN events in SP patients occurred in the first cycle before pegfilgrastim was administered. The three most frequently chosen reasons for using pegfilgrastim were planned chemotherapy with high FN risk, female gender, and advanced disease. Overall, 40 % of patients received > 90 % of their planned chemotherapy dose within 3 days of the planned schedule.

CONCLUSION

FN incidence was relatively low with pegfilgrastim PP in patients with a physician-assessed overall FN risk of ≥ 20 %. The most important reasons for pegfilgrastim use were consistent with the investigators' risk assessment and international guidelines.

Pegfilgrastim for the prevention of chemotherapy-induced febrile neutropenia in patients with solid tumors

INTRODUCTION

Neutropenia and febrile neutropenia are the most common and most severe bone marrow toxicities of chemotherapy. Recombinant granulocyte-colony stimulating factors (G-CSFs), both daily (filgrastim and biosimilars, and lenograstim) and long-acting (pegfilgrastim and lipegfilgrastim) formulations, are currently available to counteract the negative consequences of these side effects.

AREAS COVERED

The purpose of this article is to review the physiopathology of chemotherapy-induced febrile neutropenia and its consequences, and the current evidence regarding the pharmacological properties, clinical efficacy and cost-effectiveness of pegfilgrastim as a strategy to prevent chemotherapy-induced febrile neutropenia in patients with solid tumors.

EXPERT OPINION

Chemotherapy-induced febrile neutropenia and its complications are still a major health-care concern, and the inappropriate employment of G-CSFs in clinical practice can partially explain its burden. Pegfilgrastim has pharmacological advantages over daily G-CSFs that makes it easily administrable, thus reducing the chance of incorrect delivery. The once-per-cycle administration might explain the findings derived from observational studies suggesting a possible superior efficacy of pegfilgrastim over daily G-CSFs. For patients at higher risk of failure with daily G-CSF prophylaxis (e.g. risk of non-compliance, difficulties on performing regular hemograms, high risk of developing febrile neutropenia), pegfilgrastim might be the most appropriate option.

Multicentre, Prospective Observational Study of Pegfilgrastim Primary Prophylaxis in Patients at High Risk of Febrile Neutropenia in Poland: PROFIL Study

Aim of the study

PROFIL was a prospective observational study conducted to investigate physicians’ evaluation of febrile neutropenia (FN) risk and reasons for giving pegfilgrastim primary prophylaxis (PP) in routine clinical practice in Poland.

Material and methods

Adult cancer patients treated with chemotherapy (CT), assessed by investigators as having high overall FN risk, and who received pegfilgrastim in cycle 1 were enrolled between 03/2009 and 09/2010. Investigators assessed FN risk of the CT regimen, individual risk factors, and overall FN risk, and were asked to provide the most important reasons for providing pegfilgrastim PP. Investigator-assessed CT FN risk was compared with guideline classification.

Results

Data were analysed from 1006 breast, ovarian, and lung cancer, and non-Hodgkin (NHL) and Hodgkin lymphoma (HL) patients. The most important reasons for using pegfilgrastim PP were high CT FN risk and advanced disease; these were consistent across tumour types and treatment intent. The investigators generally assessed high CT FN risk in agreement with guideline classification. Febrile neutropenia occurred in 4% of patients, most commonly in HL, NHL, and patients with advanced disease.

Conclusions

High CT FN risk and advanced stage of disease were found to be the most important reasons for providing pegfilgrastim PP by physicians in Poland.

Design Rationale and Development Approach for Pegfilgrastim as a Long-Acting Granulocyte Colony-Stimulating Factor

Filgrastim, a recombinant methionyl human granulocyte colony-stimulating factor (G-CSF) (r-metHuG-CSF), is efficacious in stimulating neutrophil production and maturation to prevent febrile neutropenia (FN) in response to chemotherapy. Because of its relatively short circulating half-life, daily filgrastim injections are required to stimulate neutrophil recovery. In an effort to develop a long-acting form of filgrastim that was as safe and efficacious as filgrastim but had a longer in vivo residence time, a number of strategies were considered. Ultimately, fusion of filgrastim to polyethylene glycol (PEG) was selected. Following extensive analysis of conjugation chemistries as well as in vitro and in vivo characterization of a panel of PEGylated proteins, a construct containing a 20 kDa PEG moiety covalently conjugated to the N-terminus of filgrastim was chosen for advancement as pegfilgrastim. Pegfilgrastim is primarily cleared by neutrophils and neutrophil precursors (rather than the kidneys), meaning that clearance from the circulation is self-regulating and pegfilgrastim is eliminated only after neutrophils start to recover. Importantly, addition of PEG did not alter the mechanism of action and safety profile compared to filgrastim. Clinical evaluation revealed that a single 6 mg dose effectively reduces the duration of neutropenia and risk of FN in patients receiving chemotherapy. This work demonstrates the benefit of using PEGylation to generate pegfilgrastim, which allows for once-per-chemotherapy cycle administration while maintaining similar safety and efficacy profiles as those for multiple daily administration of filgrastim. Approaches that may provide advances for therapeutic agonists of G-CSF receptor are also discussed.

G-CSF utilization rate and prescribing patterns in United States: associations between physician and patient factors and GCSF use

Febrile neutropenia (FN) is a common complication among patients with chemotherapy-induced myelotoxicity and is associated with a number of negative outcomes including prolonged hospitalization, increased medical costs, increased risk of mortality, dose reductions, and delays. Granulocyte-colony-stimulating factor (G-CSF), granulocyte-macrophage-colony stimulating factor (GM-CSF), and pegylated G-CSF are effective at reducing risk and duration of neutropenia-related events. However, despite guidelines, the use of G-CSF and pegylated G-CSF in the United States has not been consistent and pattern of care studies have focused primarily on G-CSF. A number of studies found that G-CSF is underutilized in patients undergoing chemotherapy treatments associated with a high risk of FN, while being over utilized in patients with a low-risk FN. Wide variations in overuse, underuse, and misuse of G-CSF are associated with a number of physician and patient factors. Improved awareness of the guidelines, feedback to providers regarding proper usage, and understanding of chemotherapy regimens associated with very low risks as well as high risks (>20%) of FN is some of the approaches that could lead to improving care.

Efficacy, effectiveness and safety of long-acting granulocyte colony-stimulating factors for prophylaxis of chemotherapy-induced neutropenia in patients with cancer: a systematic review

PURPOSE

Pegfilgrastim was introduced over a decade ago. Other long-acting granulocyte colony-stimulating factors (G-CSFs) have recently been developed. We systematically reviewed the efficacy, effectiveness and safety of neutropenia prophylaxis with long-acting G-CSFs in cancer patients receiving chemotherapy.

METHODS

We performed a systematic literature search of the MEDLINE, EMBASE and Cochrane Library databases, and abstracts from key congresses. Studies of long-acting G-CSFs for prophylaxis of chemotherapy-induced neutropenia (CIN) and febrile neutropenia (FN) were identified by two independent reviewers. Abstracts and full texts were assessed for final inclusion; risk of bias was evaluated using the Cochrane's tool. Effectiveness and safety results were extracted according to study type and G-CSF used.

RESULTS

Of the 839 articles identified, 41 articles representing different studies met the eligibility criteria. In five randomised controlled trials, 11 clinical trials and 17 observational studies across several tumour types and chemotherapy regimens, pegfilgrastim was used alone or compared with daily G-CSF, no G-CSF, no upfront pegfilgrastim or placebo. Studies generally reported lower incidence of CIN (4/7 studies), FN (11/14 studies), hospitalisations (9/13 studies), antibiotic use (6/7 studies) and adverse events (2/5 studies) with pegfilgrastim than filgrastim, no upfront pegfilgrastim or no G-CSF. Eight studies evaluated other long-acting G-CSFs; most (5/8) were compared to pegfilgrastim and involved patients with breast cancer receiving docetaxel-based therapy. Efficacy and safety profiles of balugrastim and lipegfilgrastim were comparable to pegfilgrastim in phase 3 studies. Efficacy and safety of other long-acting G-CSFs were mixed.

CONCLUSIONS

Pegfilgrastim reduced the incidence of FN and CIN compared with no prophylaxis. Most studies showed better efficacy and effectiveness for pegfilgrastim than filgrastim. Efficacy and safety profiles of lipegfilgrastim and balugrastim were similar to pegfilgrastim.

Pharmacoeconomics of granulocyte colony-stimulating factor: a critical review

INTRODUCTION

In the USA, neutropenia-related hospitalization is estimated to occur in 34.2 cases per 1,000 chemotherapy-treated patients. The cost of hospitalization is significant with estimates ranging, on average, from $10,000 to $30,000 per neutropenia-related hospitalization. Prophylactic use of granulocyte colony-stimulating factor (G-CSF) significantly reduces the risk and duration of neutropenia-related negative events. However, the exact economic benefits of using G-CSF prophylactically are not completely known. The objective of this review is to examine the cost of G-CSF as primary prophylaxis (PP) as well as when used reactively to treat severe neutropenia (SN) or febrile neutropenia (FN).

METHODS

Electronic databases were searched for studies published up to January 2014.

RESULTS

The evidence supporting the cost-effectiveness of PP use of G-CSF is inconsistent. The cost savings of PP use of G-CSF associated with the reduction of neutropenia-related events are offset by the increased costs associated with improved chemotherapy administration. Cost savings due to the reduction in mortality and disease/symptoms and use of dose-dense regimens have not been adequately incorporated into previous cost-effectiveness studies. Available data suggest that using G-CSF in conjunction with antibiotics is more cost-effective than antibiotics alone when treating patients with SN/FN. Recent studies of biosimilars suggest that they are as effective as originator G-CSFs and, given their lower cost, could represent a cost-effective alternative. Finally, studies have not taken into consideration the indirect patient costs of experiencing a neutropenia-related event.

CONCLUSION

G-CSF use is effective in preventing SN/FN. Costs due to hospitalization and other neutropenia-related events are lower in patients treated with G-CSF as PP versus untreated patients. Despite this, many studies have not found solid evidence for the overall cost-effectiveness of PP use of G-CSF. One possibility for this is that patients receiving G-CSF prophylactically often receive more intense chemotherapy regimens, have better relative dose intensity, and fewer dose delays, and thereby have greater costs associated with chemotherapy administration than patients who do not receive G-CSF.

Low temperature thermal dependent Filgrastim adsorption behavior detected with ToF-SIMS

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) detected changes in Filgrastim (granulocyte colony stimulating growth factor, G-CSF) adsorption behavior at a solid interface when exposed to temperatures as low as 35 °C, i.e., before thermal denaturation, was detected by circular dichroism (CD) or dynamic light scattering (DLS). Biopharmaceuticals rely on maintaining sufficient conformation to impart correct biological function in vivo. Stability of such molecules is critical during synthesis, storage, transport, and administration. CD analysis indicated loss of structure at temperatures greater than ~60 °C, while DLS detected aggregation at ~42 °C. Furthermore, we demonstrate the nature of G-CSF interaction with a surface was altered rapidly and at relatively low temperatures. Specifically, after 10 min thermal treatment, changes in adsorption behavior occurred at 35 °C indicated by principal component analysis of spectra as primarily due to increasing yields of methionine fragments. This was likely to be due to either altering the preferential protein orientation upon adsorption or greater denaturation exposing the hydrophobic core. This investigation demonstrates the sensitivity of ToF-SIMS in studying biopharmaceutical adsorption and conformational change and can assist with studies into promoting their stability.