What type of medication is Neupogen (filgrastim)?

From the Guidelines

Neupogen (filgrastim) is a granulocyte colony-stimulating factor (G-CSF) medication that stimulates the bone marrow to produce neutrophils, a type of white blood cell essential for fighting infections. It is primarily used to treat neutropenia, a condition characterized by abnormally low levels of neutrophils, which commonly occurs as a side effect of chemotherapy 1. Neupogen is also prescribed to boost white blood cell production in patients undergoing bone marrow transplantation, those with severe chronic neutropenia, and to mobilize stem cells for collection before stem cell transplantation. The medication works by binding to specific receptors on neutrophil precursor cells in the bone marrow, promoting their proliferation, differentiation, and release into the bloodstream.

Some key points to consider when using Neupogen include:

• The dosage schedule, which typically involves administering 5 µg/kg/day of G-CSF subcutaneously 24–72 h after the last day of chemotherapy until sufficient/stable ANC recovery 1
• The route of application, which is typically subcutaneous injection
• The potential side effects, which include bone pain resulting from the rapid expansion of bone marrow activity
• The contraindications, such as use during radiotherapy to the chest due to increased rate of complications and death 1

It's worth noting that Neupogen has been shown to be effective in reducing the incidence of febrile neutropenia and other complications associated with chemotherapy 1. Additionally, the use of Neupogen has been recommended by various guidelines, including those from the American Society of Clinical Oncology (ASCO) and the European Organisation for Research and Treatment of Cancer (EORTC) 1.

In terms of specific patient populations, Neupogen may be particularly beneficial for those at high risk of developing febrile neutropenia, such as those with prior chemotherapy, abnormal hepatic and renal function, low white blood count, and planned delivery of ≥85% of the dose of chemotherapy 1. Overall, Neupogen is a valuable medication for reducing the risk of infections and other complications associated with chemotherapy, and its use should be considered in patients at high risk of developing these complications.

From the FDA Drug Label

Filgrastim is a human granulocyte colony-stimulating factor (G-CSF)‚ produced by recombinant DNA technology. Neupogen (filgrastim) is a type of biologic medication, specifically a recombinant human granulocyte colony-stimulating factor (G-CSF) 2.

• It is used to stimulate the production of white blood cells, particularly neutrophils.
• The main mechanism of action is to increase the number of neutrophils in the blood, which helps to fight infection.
• Neupogen is classified as a growth factor and is used to reduce the incidence of febrile neutropenia in patients receiving chemotherapy.

From the Research

Neupogen (Filgrastim) Medication Type

• Neupogen, also known as filgrastim, is a recombinant methionyl human granulocyte colony-stimulating factor (G-CSF) 3, 4, 5.
• It is used to stimulate neutrophil production and maturation, preventing febrile neutropenia (FN) in response to chemotherapy 3, 6, 4.
• Filgrastim works by stimulating the proliferation and differentiation of neutrophil progenitor cells 7, 5.

Mechanism of Action and Administration

• Filgrastim has a relatively short circulating half-life, requiring daily injections to stimulate neutrophil recovery 3, 6.
• A pegylated form of filgrastim, pegfilgrastim, has been developed to provide a longer-acting alternative, allowing for once-per-chemotherapy cycle administration 3, 6, 4.
• Pegfilgrastim has self-regulating, patient-specific pharmacokinetics, making it possible to give the treatment as a single dose once per chemotherapy cycle 6.

Clinical Uses and Efficacy

• Filgrastim and pegfilgrastim are used to reduce the incidence and severity of neutropenia and febrile neutropenia in patients receiving myelosuppressive chemotherapy 6, 4.
• Clinical trials have shown that filgrastim and pegfilgrastim are safe and effective in preventing febrile neutropenia and reducing the need for chemotherapy dose modification 6, 4, 5.
• Filgrastim has also been used to support dose-intensification of chemotherapy and to accelerate neutrophil recovery in patients with severe chronic neutropenia and idiosyncratic drug-induced agranulocytosis 4, 5.