A pilot study on intermittent every other days of 5-dose Filgrastim compared with single Pegfilgrastim in breast Cancer patients receiving adjuvant Docetaxel, doxorubicin, and cyclophosphamide (TAC) chemotherapy

Assessing the Optimal Regimen: A Systematic Review and Network Meta-Analysis of the Efficacy and Safety of Long-Acting Granulocyte Colony-Stimulating Factors in Patients with Breast Cancer

Patients with breast cancer undergoing chemotherapy are susceptible to prolonged and severe neutropenia. Multiple biosimilars of long-acting granulocyte colony-stimulating factors (LA-G-CSFs) have been newly developed to prevent this disease. Nonetheless, which LA-G-CSF regimen has the optimal balance of efficacy and safety remains controversial. Moreover, there is a lack of evidence supporting clinical decisions on LA-G-CSF dose escalation in poor conditions. PubMed, Embase, Cochrane Library, Web of Science, and several Chinese databases were searched (December 2022) to collect randomized controlled trials (RCTs) about LA-G-CSFs preventing chemotherapy-induced neutropenia in breast cancer patients. No restrictions were imposed on language. A Bayesian network meta-analysis was performed. We assessed the incidence of severe neutropenia (SN) and febrile neutropenia (FN), the duration of SN (DSN), and the absolute neutrophil account recovery time (ANCrt) for efficacy, while the incidence of severe adverse events (SAE) was assessed for safety. The study was registered in PROSPERO (CRD42022361606). A total of 33 RCTs were included. Our network meta-analysis demonstrated that lipegfilgrastim 6 mg and eflapegrastim 13.2 mg outperformed other LA-G-CSFs with high efficacy rates and few safety concerns (SUCRA of lipegfilgrastim 6 mg: ANC rt 95.2%, FN 97.4%; eflapegrastim 13.2 mg: FN 87%, SN 89.3%). Additionally, 3.6 mg, 4.5 mg, 6 mg, and 13.2 mg dosages all performed significantly better than 1.8 mg in reducing the duration of SN (3.6 mg: DSN, SMD -0.68 [-1.13, -0.22; moderate]; 4.5 mg: -0.87 [-1.57, -0.17; low]; 6 mg: -0.89 [-1.49, -0.29; moderate]; 13.2 mg: -1.02 [1.63, -0.41; high]). Increasing the dosage from the guideline-recommended 6 mg to 13.2 mg can reduce both the duration and incidence of SN (SMD -0.13 [-0.24 to -0.03], RR 0.65 [0.43 to 0.96], respectively), with no significant difference in SAE. For patients with breast cancer, lipegfilgrastim 6 mg and eflapegrastim 13.2 mg might be the most effective regimen among LA-G-CSFs. Higher doses of LA-G-CSF may enhance efficacy without causing additional SAEs.

Pegfilgrastim for primary prophylaxis of febrile neutropenia in multiple myeloma

Multiple myeloma (MM) survival rates have been substantially increased thanks to novel agents that have improved survival outcomes and shown better tolerability than treatments of earlier years. These new agents include immunomodulating imide drugs (IMiD) thalidomide and lenalidomide, the proteasome inhibitor bortezomib (PI), recently followed by new generation IMID pomalidomide, monoclonal antibodies daratumumab and elotuzumab, and next generation PI carfilzomib and ixazomib. However, even in this more promising scenario, febrile neutropenia remains a severe side effect of antineoplastic therapies and can lead to a delay and/or dose reduction in subsequent cycles. Supportive care has thus become key in helping patients to obtain the maximum benefit from novel agents. Filgrastim is a human recombinant subcutaneous preparation of G-CSF, largely adopted in hematological supportive care as "on demand" (or secondary) prophylaxis to recovery from neutropenia and its infectious consequences during anti-myeloma treatment. On the contrary, pegfilgrastim is a pegylated long-acting recombinant form of granulocyte colony-stimulating factor (G-CSF) that, given its extended half-life, can be particularly useful when adopted as "primary prophylaxis," therefore before the onset of neutropenia, along chemotherapy treatment in multiple myeloma patients. There is no direct comparison between the two G-CSF delivery modalities. In this review, we compare data on the two administrations' modality, highlighting the efficacy of the secondary prophylaxis over multiple myeloma treatment. Advantage of pegfilgrastim could be as follows: the fixed administration rather than multiple injections, reduction in neutropenia and febrile neutropenia rates, and, finally, a cost-effectiveness advantage.