Efficacy of delayed pegfilgrastim administration following consolidation therapy with high-dose cytarabine (HiDAC) in acute myeloid leukemia (AML) patients.

PURPOSE: To study the effects of delaying pegfilgrastim administration following high-dose cytarabine (HiDAC) consolidation in AML patients on time to neutrophil count recovery, infectious complications, and survival. METHODS: Single-center retrospective chart review of 55 patients receiving pegfilgrastim as early administration (within 72 h) or delayed administration (after 72 h) of HiDAC. RESULTS: The difference in neutrophil recovery time was similar between the early and delayed groups (18 days versus 19 days, p < 0.28). Infections were seen in four patients in the early administration group following chemotherapy compared to none in the delayed group (p = 0.04). Febrile neutropenia rates were also decreased in the delayed administration group (23.1% versus 10.3%, p = 0.28) as well as a trend towards longer median survival (16 months versus 19 months, p = 0.69) and overall survival (21 months versus 31 months, p = 0.47). CONCLUSION: A difference in time to neutrophil recovery was not observed between the early and delayed administration groups yet decreased infectious complications may support the delayed administration of pegfilgrastim in these patients.

Filgrastim Use in the Treatment of Azathioprine-Induced Myelosuppression Toxicity After Prescription Error in the Feline.

Only one report on the successful use of filgrastim (granulocyte colony-stimulating factor) in cats for severe neutropenia following azathioprine toxicity exists. Here, we report on a case in which a cat was prescribed methimazole but the medication was filled incorrectly with azathioprine tablets and the prescription label indicated a methimazole dosing regimen that was administered for three days before recognition of the error. On presentation, the cat's physical examinations were consistent with previous examinations before ingestion of azathioprine. A complete blood cell count revealed neutropenia and leukopenia. The cat later developed hyporexia, dehydration, and vomiting. Treatment included antinausea and appetite stimulant medications, filgrastim, and antibiotics. Filgrastim given as subcutaneous injections over the course of treatment increased neutrophil cell counts after suppression. The cat made a full recovery after responding to the treatment protocol. Based on the perceived response to filgrastim in this single feline case report, its use can be considered for the treatment of azathioprine-induced neutropenia in cats.

Aortitis after switching short-acting granulocyte colony-stimulating factors in a lymphoma patient with HLA-B52.

Aortitis is a rare adverse event of granulocyte colony-stimulating factor (G-CSF) treatment. Several previous studies have described recurrent aortitis caused by re-administration of the same G-CSF. However, no previous studies have examined the safety of switching between short-acting G-CSFs in patients who develop aortitis. We report the case of a 55-year-old man with refractory diffuse large B-cell lymphoma, who developed G-CSF-associated aortitis. The aortitis was triggered by filgrastim and recurred after treatment with lenograstim. The patient possessed human leukocyte antigen B52, which has been implicated in Takayasu arteritis. In addition, a drug-induced lymphocyte stimulation test for lenograstim performed upon detection of recurrent G-CSF-associated aortitis produced a positive result. Our case suggests that switching from one short-acting G-CSF to another does not prevent recurrence of G-CSF-associated aortitis. Although the etiology of G-CSF-associated aortitis has not been fully elucidated, our case also suggests that some patients may be genetically predisposed to aortitis.

Optimal timing of prophylactic pegylated G-CSF after chemotherapy administration for patients with cancer: a systematic review and meta-analysis from Clinical Practice Guidelines for the use of G-CSF 2022.

INTRODUCTION: The timing of prophylactic pegylated granulocyte colony-stimulating factor (G-CSF) administration during cancer chemotherapy varies, with Day 2 and Days 3-5 being the most common schedules. Optimal timing remains uncertain, affecting efficacy and adverse events. This systematic review sought to evaluate the available evidence on the timing of prophylactic pegylated G-CSF administration. METHODS: Based on the Minds Handbook for Clinical Practice Guideline Development, we searched the PubMed, Ichushi-Web, and Cochrane Library databases for literature published from January 1990 to December 2019. The inclusion criteria included studies among the adult population using pegfilgrastim. The search strategy focused on timing-related keywords. Two reviewers independently extracted and assessed the data. RESULTS: Among 300 initial search results, only four articles met the inclusion criteria. A meta-analysis for febrile neutropenia incidence suggested a potential higher incidence when pegylated G-CSF was administered on Days 3-5 than on Day 2 (odds ratio: 1.27, 95% CI 0.66-2.46, p = 0.47), with a moderate certainty of evidence. No significant difference in overall survival or mortality due to infections was observed. The trend of severe adverse events was lower on Days 3-5, without statistical significance (odds ratio: 0.72, 95% CI 0.14-3.67, p = 0.69) and with a moderate certainty of evidence. Data on pain were inconclusive. CONCLUSIONS: Both Day 2 and Days 3-5 were weakly recommended for pegylated G-CSF administration post-chemotherapy in patients with cancer. The limited evidence highlights the need for further research to refine recommendations.

[Timing of Administration of Pegfilgrastim and Prophylaxis for Febrile Neutropenia for Patients with Early Breast Cancer Receiving Chemotherapy].

Febrile neutropenia(FN)causes a prolonged treatment schedule and decreased relative dose intensity(RDI)during cancer chemotherapy, which adversely affects prognosis. In recent years, dose-dense(dd)chemotherapy has been used as adjuvant chemotherapy for patients with breast cancer based on the results of improved disease-free survival according to meta-analysis data. Regarding neoadjuvant chemotherapy for human epidermal growth factor receptor 2-positive breast cancer, taxanes and trastuzumab with the addition of pertuzumab have shown higher pathological complete response rates and elevated incidences of FN. One hundred seventy-six patients received pegfilgrastim(PEG)prophylaxis between January 2011 and January 2023. Until 2019, the median day of PEG prophylaxis was day 4 from chemotherapy completion(days 2- 3, 14 cases; day 4, 41 cases; and day 5, 8 cases)with antibiotic prophylaxis in 58 patients(92%). FN was observed in 19 cases(30%). The RDIs of TC and FEC were 96.8% and 96.0%, respectively. Meanwhile, the median day of PEG prophylaxis after 2020 was day 2 from chemotherapy completion(days 2-3, 108 cases; day 4, 4 cases; and day 5, 1 case)without antibiotic prophylaxis. FN was not observed in any of the cases. The RDI of all regimens was 99.7%. Although there were some differences in chemotherapy regimens, an earlier timing of PEG prophylaxis(especially 24-48 hours from chemotherapy completion)has been shown to reduce the incidence of FN and increase the RDI.

Characterization of PEGylation sites in Neulasta and a biosimilar candidate with a combined fragmentation strategy in mass spectrometry analysis.

In the development of biosimilar products to Neulasta, it is essential to determine the intact molecular mass and confirm precise PEGylation sites. In this study, we applied a combination of techniques, including post-column addition of triethylamine in reversed-phase liquid chromatography-mass spectrometry (RPLC-MS) to determine the intact molecular mass, and in-source fragmentation (ISF) and higher-energy collision dissociation-tandem mass spectrometry (HCD-MS/MS) to identify the PEGylation site. Our results show that both the pegfilgrastim biosimilar candidate and Neulasta lots are mono-PEGylated at the N-terminal end. Furthermore, we show that the combined ISF and HCD-MS/MS method can be used for identifying the PEGylation sites in the diPEGylated variant of pegfilgrastim. The diPEGylated variant has modification sites at the N-terminal end and a lysine at position 35 in the protein sequence.

Filgrastim biosimilar (EP2006): A review of 15 years' post-approval evidence.

Filgrastim is approved for several indications, including reduction of the incidence and duration of chemotherapy-induced neutropenia and for stem cell mobilization. The filgrastim biosimilar, EP2006, has been available in Europe since 2009, and in the United States since 2015. In this time, preclinical and clinical data used to support the approval of EP2006 have been published. These data established the biosimilarity of EP2006 to reference filgrastim in terms of structure, pharmacokinetics, pharmacodynamics, efficacy, safety, and immunogenicity. Additional real-world evidence studies have also demonstrated equivalent efficacy and safety of EP2006 compared with reference filgrastim, both in the reduction of neutropenia and in stem cell mobilization in clinical practice. This review summarizes these preclinical, clinical, and real-world data, as well as the available cost-effectiveness data, for EP2006 since its approval 15 years ago.

Prophylactic pegfilgrastim reduces febrile neutropenia in ramucirumab plus docetaxel after chemoimmunotherapy in advanced NSCLC: post hoc analysis from NEJ051.

Ramucirumab plus docetaxel (RD) can cause febrile neutropenia (FN), which frequently requires the prophylactic administration of pegfilgrastim. However, the effects of prophylactic pegfilgrastim on FN prevention, therapeutic efficacy, and prognosis after RD have not been fully evaluated in patients with advanced non-small-cell lung cancer (NSCLC). Two hundred and eighty-eight patients with advanced NSCLC who received RD as second-line therapy after platinum-based chemotherapy plus PD-1 blockade were included. Patients were divided into groups with and without prophylactic pegfilgrastim, and adverse events, efficacy, and prognosis were compared between both groups. Of the 288 patients, 247 received prophylactic pegfilgrastim and 41 did not. The frequency of grade 3/4 neutropenia was 62 patients (25.1%) in the pegfilgrastim group and 28 (68.3%) in the control group (p < 0.001). The frequency of FN was 25 patients (10.1%) in the pegfilgrastim group and 10 (24.4%) in the control group (p = 0.018). The objective response rate was 31.2% and 14.6% in the pegfilgrastim and control groups (p = 0.039), respectively. The disease control rate was 72.9% in the pegfilgrastim group and 51.2% in the control group (p = 0.009). Median progression free survival was 4.3 months in the pegfilgrastim group and 2.5 months in the control group (p = 0.002). The median overall survival was 12.8 and 8.1 months in the pegfilgrastim and control groups (p = 0.004), respectively. Prophylactic pegfilgrastim for RD reduced the frequency of grade 3/4 neutropenia and febrile neutropenia and did not appear to be detrimental to patient outcome RD.Clinical Trial Registration Number: UMIN000042333.

Docetaxel, cisplatin, and fluorouracil with pegfilgrastim on day 3 as neoadjuvant chemotherapy for esophageal cancer.

PURPOSE: A high risk of febrile neutropenia (FN) from neoadjuvant chemotherapy with docetaxel, cisplatin, and fluorouracil (DCF) for esophageal cancer has been reported. The optimal timing of prophylactic use of pegfilgrastim remains to be elucidated. To evaluate the effect of pegfilgrastim administered on day 3, we conducted a feasibility study. METHODS: Chemotherapy consisted of intravenous administration of docetaxel (70 mg/m2 per day) and cisplatin (70 mg/m2 per day) on day 1 and continuous infusion of 5-fluorouracil (750 mg/m2 per day) on days 1-5. Pegfilgrastim was given as a single subcutaneous injection at a dose of 3.6 mg on day 3 during each treatment course. This regimen was repeated every 3 weeks for up to a maximum of three courses. Prophylactic antibiotics were not needed but were allowed to be given at the discretion of the physician. The primary endpoint was the incidence of FN. RESULTS: Twenty-six patients were administered DCF in combination with pegfilgrastim on day 3. After the first course of DCF, 10 out of 26 patients (38.5%) experienced grade 4 neutropenia, and two patients (7.7%) experienced FN. Of the 14 patients who did not receive prophylactic antibiotics, four had grade 4 neutropenia, including two who developed FN. On the contrary, of the 12 patients who received prophylactic levofloxacin, six had grade 4 neutropenia, but no cases of FN were observed. CONCLUSION: Administration of pegfilgrastim on day 3 was not sufficient to prevent FN due to DCF treatment, and prophylactic administration of both pegfilgrastim and antibiotics could be a solution.

Effect of Loratadine for Pegfilgrastim-Induced Bone Pain.

AIMS: Breast cancer patients on chemotherapy who receive pegfilgrastim to prevent neutropenia may experience severe bone pain as a side effect. Traditional treatment recommendations include nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, opioids, and/or antihistamine use. However, little research was found comparing these interventions. The study aim was to address the gaps in literature and to explore the use of and perceived effectiveness of loratadine versus acetaminophen or NSAIDs in women with breast cancer treated with pegfilgrastim. This study also sought to understand how patients became aware of loratadine or other treatments for management of bone pain. DESIGN/METHODS: This cross-sectional study used survey methods to collect data from 66 adult female breast cancer patients receiving chemotherapy with pegfilgrastim. RESULTS: The incidence of bone pain was 45% (n = 30) in our sample, but more than half (n = 45; 69%) of the women took either acetaminophen, NSAIDs, or loratadine alone or in combination to prevent bone pain. All medication were rated as effective by patients, with acetaminophen slightly more effective than loratadine, and loratadine more effective than NSAIDs. CONCLUSIONS: Acetaminophen, NSAIDs, and loratadine are easily available and inexpensive. However, unlike acetaminophen and NSAIDs, loratadine is dosed once a day and well tolerated with minimal adverse effects. CLINICAL IMPLICATIONS: Randomized controlled trials are needed to adequately assess the effectiveness of all three medication options. Because little is known about optimal use of any of these medications for pegfilgrastim-induced bone pain, it is also important to identify the optimal time to initiate treatment and ideal treatment duration.

A Randomized, Open-Label Study Conducted to Evaluate the Bioequivalence of Pegfilgrastim-cbqv On-Body Injector Versus Prefilled Syringe in Healthy Male Participants.

INTRODUCTION: To help prevent febrile neutropenia, pegfilgrastim-cbqv (UDENYCA®; Coherus BioSciences), a pegfilgrastim (NEULASTA®; Amgen) biosimilar, is administered 24-96 h after myelosuppressive chemotherapy. Delivery of pegfilgrastim-cbqv using an on-body injector (OBI) provides an alternative method of administration, affording options in drug delivery. This study aimed to establish pharmacokinetic (PK) and pharmacodynamic (PD) bioequivalence and assess the safety of pegfilgrastim-cbqv administered using an OBI compared with a prefilled syringe (PFS). METHODS: In this open-label, two-period crossover study, healthy adult male participants (N = 189) were randomly assigned 1:1 to receive pegfilgrastim-cbqv 6 mg subcutaneously using an OBI (n = 92) or a PFS (n = 95) in period 1 and then an injection via the other method in period 2. Primary PK end points were area under the concentration-time curve from time 0 to infinity, area under the concentration-time curve from time 0 to the last quantifiable concentration, and maximum plasma concentration. Secondary PD end points, safety, immunogenicity, and tolerability were also assessed. RESULTS: The 90% confidence intervals (CIs) of the geometric mean ratios for the PK and PD end points fell within the predetermined range (80-125%), indicating PK and PD bioequivalence between pegfilgrastim-cbqv OBI and pegfilgrastim-cbqv PFS. Treatment-emergent adverse events (TEAEs) occurred in 87.8% and 75.8% of participants in the OBI and PFS groups, respectively. Most TEAEs were musculoskeletal effects. The most common OBI-related TEAE was injection site erythema (31.7%), which was mild, transient, and self-limiting. The incidence of treatment-emergent antidrug antibodies (ADAs) was similar between the OBI and PFS. ADAs had no apparent impact on PK, PD, or safety. Neutralizing antibodies were not detected in any participant. CONCLUSIONS: Results of the study showed PK and PD bioequivalence of pegfilgrastim-cbqv administered using OBI compared with PFS. OBI and PFS administration had similar safety, tolerability, and immunogenicity profiles. No unexpected safety signals were identified. Graphical Abstract available for this article.

Febrile neutropenia is when a patient has a fever and a lower-than-normal number of white blood cells. When white blood cell counts are low, patients are more susceptible to opportunistic infections as a result of their weakened immune systems. Severe febrile neutropenia can lead to the stopping or delaying of chemotherapy. The drug pegfilgrastim-cbqv is used 24­96 h after chemotherapy to stimulate the growth of white blood cells. Pegfilgrastim-cbqv is available in a single-dose prefilled syringe and in a prefilled autoinjector. If a patient cannot inject themselves with the drug, they must go to a clinic for the injection. Using an on-body injector applied to the skin that automatically injects the drug at a specific time could eliminate the need to go to the clinic. During this study, healthy adult male participants were given pegfilgrastim-cbqv through an on-body injector or a prefilled syringe to investigate if the movement of the drug into, through, and out of the body (pharmacokinetics) and the physiological action of the drug in the body (pharmacodynamics) were similar between the two injection methods. Side effects were also studied. The researchers found that the pharmacokinetics and pharmacodynamics for pegfilgrastim-cbqv given by on-body-injector or prefilled syringe were similar. The number and types of side effects were also similar. The most common side effect for the on-body injector was mild erythema at the injection site. This side effect resolved by itself. The treatment benefit and safety of pegfilgrastim-cbqv were very similar regardless of how the drug was administered.

Efficacy and safety of biosimilar Peg-filgrastim after autologous stem cell transplant in myeloma and lymphoma patients: a comparative study with biosimilar Filgrastim, Lenograstim, and originator Peg-filgrastim.

Data about biosimilar Peg-filgrastim (bioPEG) in autologous stem cell transplant (ASCT) are still scarce. The aim of this study has been to assess efficacy and safety of bioPEG among lymphoma and myeloma patients undergoing ASCT, comparing these data with historical controls receiving other G-CSFs. Furthermore, an economic evaluation has been included to estimate the savings by using bioPEG. This is a prospective cohort study comparing lymphoma and myeloma patients undergoing ASCT and receiving bioPEG (n = 73) with three historical consecutive cohorts collected retrospectively who received other G-CSFs (Lenograstim - Leno - n = 101, biosimilar Filgrastim - bioFIL n = 392, and originator Peg-filgrastim - oriPEG n = 60). We observed a significantly shorter time to neutrophils and platelet engraftment (p < 0.001) in patients treated with bioPEG and oriPEG. Moreover, patients who received bioPEG showed a shorter hospitalization time (p < 0.001) and a lower transfusion need (p < 0.001). We did not observe any significant difference in terms of transplant-related mortality, mucositis, and diarrhea among the four groups. No serious adverse events were associated with bioPEG. Similar data were obtained after running a stratified analysis for lymphomas and myeloma separately conducted by using a propensity score matching. The average total cost per patient of bioPEG was € 18218.9 compared to € 23707.8, € 20677.3 and € 19754.9 of Leno, oriPEG, and bioFIL, respectively. In conclusion, bioPEG seems to be as effective as the originator and more effective than short-acting G-CSFs in terms of post-transplant engraftment in myeloma and lymphoma patients undergoing ASCT. Moreover, bioPEG was cost-effective when compared with the other G-CSFs.

Pegfilgrastim for the management of neutropenia during neoadjuvant chemotherapy with docetaxel, cisplatin, and 5-fluorouracil in esophageal cancer patients.

BACKGROUND: Neoadjuvant docetaxel, cisplatin, and 5-fluorouracil (DCF) therapy is a new standard for locally advanced esophageal squamous cell carcinoma. The optimal timing of pegfilgrastim with the DCF regimen to prevent febrile neutropenia (FN) remains controversial. The effectiveness of concomitant pegfilgrastim administration with continuous 5-fluorouracil (5-FU) infusion in the DCF regimen was therefore assessed. METHODS: All patients who received neoadjuvant DCF for esophageal cancer were retrospectively assessed. Patients who had been scheduled to receive pegfilgrastim on days 3-5 (early group) or days 7-9 (regular group) of the DCF regimen were included. Uni- and multivariate analyses were used to assess risk factors for FN. RESULTS: Eighty-eight patients were included in the analysis. The 26 patients in the early group received pegfilgrastim as scheduled. In the 62 patients of the regular group, 51 received pegfilgrastim at a median of 7 days after starting DCF chemotherapy. However, 11 patients in the regular group could not receive pegfilgrastim. Twenty-two patients of the regular group and 2 patients of the early group developed FN after the first session of DCF. Early administration of pegfilgrastim and grade 4 neutropenia were significantly associated with onset of FN, with multivariate analysis identifying early administration of pegfilgrastim as an independent preventive factor and grade 4 neutropenia as a risk factor, after adjusting for sex and age. CONCLUSION: Early pegfilgrastim administration is a safe approach that reduces the incidence of FN in DCF therapy. Using pegfilgrastim with continuous 5-FU infusion in the DCF regimen represents a reasonable option to prevent FN.

Achieving white blood cell equity: are the safety profiles of biosimilar and reference pegfilgrastims comparable?

Biosimilars can provide choices for patients and may provide cost savings; however, their uptake has been slow in the USA, in part due to limited knowledge. To provide additional confidence in US pegfilgrastim biosimilars, this narrative review compared the safety profiles of biosimilar pegfilgrastims, currently approved or filed for approval in the USA, with the EU- and US-approved reference pegfilgrastims. Headache and bone pain were common to biosimilars and reference products and occurred at a similar incidence. Clinical trial data on the safety profiles of biosimilar pegfilgrastims and reference products have demonstrated similarity and comparability, with no unexpected safety outcomes. Overall, the safety profiles of biosimilar pegfilgrastims and reference pegfilgrastims demonstrated a high degree of similarity and comparability.

Pegfilgrastim is a biologic drug (one made in living cells such as bacteria) that is given to some patients being treated for cancer. Pegfilgrastim is prescribed to reduce a patient's risk of infection due to a weakened immune system caused by various chemotherapy treatment plans. A biosimilar is a type of biologic medicine that is highly similar to a US FDA-approved reference biologic, and is often cheaper, making it more widely available to patients. As of March 2023, there are eight pegfilgrastim biosimilars (six approved and two awaiting approval by the FDA). This review compared the side effects for the reference pegfilgrastim with the biosimilar pegfilgrastims. The side effects in general and the side effects from treatment were similar for the reference pegfilgrastim and for the biosimilar pegfilgrastims, with the most common side effects being headache and bone pain. Serious side effects such as allergic reactions or problems with the spleen were very low and were also similar between the reference pegfilgrastim and the biosimilar pegfilgrastims. These results show that the safety of the biosimilar pegfilgrastims was similar to the reference pegfilgrastim, with no unexpected side effects. With comparable safety to their reference product, biosimilars have the potential to improve patient access to more affordable treatment options.

Filgrastim-induced hemophagocytic lymphohistiocytosis in a patient with mantle cell lymphoma: A case report.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease potentially induced by various causes. Very few reports have described HLH induced by granulocyte colony-stimulating factor (G-CSF) and those few previous reports have uniformly indicated that continuing G-CSF is unfeasible once HLH has been induced. A 52-year-old Japanese man who had been diagnosed with mantle cell lymphoma with systemic and central nervous system involvements received rituximab, hyper-fractionated cyclophosphamide, vincristine, Adriamycin and dexamethasone (R-HCVAD)/methotrexate and cytarabine. During the second cycle of R-HCVAD, the patient developed severe back pain, thrombocytopenia, elevated serum lactate dehydrogenase and ferritin levels, and hemophagocytosis in the bone marrow. Complete remission (CR) of mantle cell lymphoma was confirmed on whole-body computed tomography, brain magnetic resonance imaging, and bone marrow biopsy. The patient was diagnosed with HLH induced by filgrastim. HLH recovered with intravenous methylprednisolone at 1 g/day for 3 days, followed by oral prednisolone tapered off over 5 days. The patient continued chemotherapy with a change in the G-CSF formulation from filgrastim to lenograstim and prophylactic administration of corticosteroids. He safely completed scheduled chemotherapy without recurrence of HLH and successfully maintained CR of lymphoma. Although rare, G-CSF potentially induces HLH. Changing the G-CSF formulation and steroid prophylaxis may allow safe continuation of G-CSF.

Efficacy and Safety of Single-dose Pegfilgrastim for CD34 + Cell Mobilization in Healthy Volunteers: A Phase 2 Study.

BACKGROUND: Pegfilgrastim, a long-acting form of granulocyte-colony stimulating factor, with a convenient single-injection dosage, is being investigated for peripheral blood stem cell (PBSC) mobilization in healthy volunteers. However, data on the adequate dose of pegfilgrastim for PBSC mobilization are limited. This phase 2, single-arm study evaluated the efficacy and safety of pegfilgrastim for PBSC mobilization in healthy volunteers. METHODS: The study comprised 2 phases: pilot (steps 1-3, dose escalation, a single subcutaneous dose of 3.6, 7.2, and 10.8 mg pegfilgrastim, respectively) and evaluation (step 4, efficacy and safety assessments). The primary endpoint was the proportion of subjects who achieved mobilization of ≥20 × 10 6 /L cluster of differentiation 34 positive (CD34 + ) cells. RESULTS: Thirty-five subjects (6 each in steps 1 and 2 and 23 in step 4) were included. In the pilot phase, step 3 with a 10.8 mg dose was not conducted due to favorable outcomes in step 2 (desired CD34 + cell count), at 7.2 mg pegfilgrastim, which was identified as the optimal dose for the evaluation phase. In the evaluation phase, successful CD34 + mobilization was achieved in all 23 subjects. The mean peripheral blood CD34 + cells count peaked on day 5. Back pain, thrombocytopenia, transient elevations of alkaline phosphatase, and lactate dehydrogenase were the most common adverse events. All adverse events were mild, and none led to study discontinuation. CONCLUSIONS: A single-dose pegfilgrastim successfully mobilized an optimal number of CD34 + cells and was well tolerated. Pegfilgrastim could be an alternative option for PBSC mobilization in healthy volunteers. The trial was registered at www.clinicaltrials.gov (NCT03993639).

Aggregation of human plasma and of human blood induced in vitro by filgrastim originator product; effect of PEGylation.

We herein report that filgrastim product Neupogen® and the filgrastim formulation buffer induced aggregate formation when mixed in vitro with human plasma, and formation of large membranous erythrocyte aggregates when mixed with human blood, similar to the aggregation induced by pegfilgrastim and by pegfilgrastim buffer [T. Arvinte, E. Poirier, N. Ersayin, G. Darpin, A. Cudd, J. Dowd, S. Brokx, Aggregation of human plasma and of human blood induced in vitro by pegfilgrastim originator formulation buffer and pegfilgrastim products, Eur. J. Pharmaceut. Biopharmaceut. (2023), doi: 10.1016/j.ejpb.2023.10.019]. The data identify the filgrastim buffer (which is practically the same in filgrastim and pegfilgrastim products) as the main driver of human plasma and blood aggregation. Kinetic experiments showed differences in the extent of plasma aggregation induced by a filgrastim product manufactured in EU and one manufactured in USA. Human donor variability in the plasma aggregation induced by filgrastim was observed. To study the effect of PEGylation of the filgrastim protein on plasma aggregation we compared filgrastim (Neupogen®) with pegfilgrastim (Neulasta®) solutions at the same protein concentration. These data show that PEGylation has a beneficial effect in inhibiting to an extent plasma aggregation. Interestingly, 20 kDa polyethylene glycol in the filgrastim buffer induced more plasma aggregation compared to the buffer, similar to the aggregation induced by pegfilgrastim. For intravenous infusion filgrastim solutions (300 µg/ml, vials only) may be diluted in 5 % dextrose from a concentration of 300 µg/ml to 5 µg/ml. Aggregation of human plasma was also induced by filgrastim solutions diluted in 5 % dextrose to 50 µg/ml, 15 µg/ml and 5 µg/ml filgrastim, as well as by the filgrastim buffer similarly diluted in 5 % dextrose (1:6, 1:20 and 1:60 dilution). These data show that filgrastim solutions used for intravenous administration in patients induce human plasma aggregation in vitro. Such aggregation phenomena may be related to known infusion side effects of filgrastim therapy.

Filgrastim and infliximab biosimilar uptake in Medicare Advantage compared with Traditional Medicare, 2016-2019.

BACKGROUND: Medicare Advantage (MA) and Traditional Medicare face different financing structures and incentives and may implement different strategies to encourage biosimilar uptake. Strategies used by health insurers can influence biosimilar uptake, which can in turn promote savings to insurers and patients. OBJECTIVE: To compare filgrastim and infliximab biosimilar uptake between MA and Traditional Medicare from 2016 to 2019 and examine biosimilar uptake by different MA carriers and plan types (Health Maintenance Organization [HMO] or Preferred Provider Organization). METHODS: We use a 2016-2019 nationally representative random 20% sample of the carrier (physician) and outpatient paid claims for Traditional Medicare data and final-action carrier and outpatient records for MA data. We compare quarterly biosimilar uptake from 2016 to 2019 for the first 2 drugs with biosimilar competition: (1) filgrastim, (Neupogen, originator), and biosimilars tbo-filgrastim (GRANIX) and filgrastim-sndz (ZARXIO), and (2) infliximab (Remicade, originator), and biosimilars infliximab-dyyb (Inflectra) and infliximab-abda (Renflexis). RESULTS: From their introduction, there was consistently greater uptake of filgrastim and infliximab biosimilars in MA compared with Traditional Medicare. By Q4 2019, filgrastim biosimilar uptake was 7.6 percentage points higher in MA (80.3%) than Traditional Medicare (72.7%). By Q4 2019, infliximab biosimilar uptake was 28.7% and 15.4% in MA and Traditional Medicare, respectively. Kaiser HMO plans were primarily responsible for the higher uptake of biosimilars in MA; in Q4 2019, filgrastim and infliximab biosimilar uptake was 98.8% and 78.8%, respectively. CONCLUSIONS: Our findings suggest that filgrastim and infliximab biosimilar uptake is greater in MA compared with Traditional Medicare, which is driven in part by particularly high uptake of biosimilars in MA Kaiser HMO plans. This highlights the need for future work to examine specific strategies and levers employed by MA Kaiser HMO plans and other insurers to increase biosimilar uptake, which can lead to cost savings for physician-administered drugs.

Granulocyte Colony-Stimulating Factor (Neupogen®; Filgrastim) Accelerates Neutrophil Recovery in a Rodent Model of Sulfur Mustard-Induced Hematologic Toxicity.

OBJECTIVE: Evidence of myelosuppression has been negatively correlated with patient outcomes following cases of high dose sulfur mustard (SM) exposure. These hematologic complications can negatively impact overall immune function and increase the risk of infection and life-threatening septicemia. Currently, there are no approved medical treatments for the myelosuppressive effects of SM exposure. METHODS: Leveraging a recently developed rodent model of SM-induced hematologic toxicity, post-exposure efficacy testing of the granulocyte colony-stimulating factor drug Neupogen® was performed in rats intravenously challenged with SM. Before efficacy testing, pharmacokinetic/pharmacodynamic analyses were performed in naïve rats to identify the apparent human equivalent dose of Neupogen® for efficacy evaluation. RESULTS: When administered 1 d after SM-exposure, daily subcutaneous Neupogen® treatment did not prevent the delayed onset of hematologic toxicity but significantly accelerated recovery from neutropenia. Compared with SM controls, Neupogen®-treated animals recovered body weight faster, resolved toxic clinical signs more rapidly, and did not display transient febrility at time points generally concurrent with marked pancytopenia. CONCLUSIONS: Collectively, this work corroborates the results of a previous pilot large animal study, validates the utility of a rodent screening model, and provides further evidence for the potential clinical utility of Neupogen® as an adjunct treatment following SM exposure.