NENTAS 300 SOLUTION FOR INJECTION

Indications

• Neutropenia due to chemotherapy
• Neutropenia in patients with bone marrow disorders
• Prevention of febrile neutropenia in cancer patients
• Mobilization of peripheral blood stem cells

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations.

Adults: Refer to established guidelines for specific dosing recommendations based on the indication and patient factors.

Mechanism of action

Filgrastim binds to the G-CSF receptor on hematopoietic cells, stimulating the proliferation and differentiation of myeloid progenitor cells into neutrophils. This action increases the absolute neutrophil count (ANC) and enhances the function of mature neutrophils, promoting immune responses.

Pharmacodynamics

Filgrastim increases the production of neutrophils, which are crucial for the body’s defense against infections. The drug not only promotes the proliferation of neutrophil precursors but also enhances their function, including chemotaxis and phagocytosis. This leads to a rapid increase in neutrophil levels in the bloodstream, typically observed within 24 hours of administration.

Pharmacokinetics

Filgrastim has a half-life of approximately 3.5 hours after subcutaneous injection. It is predominantly eliminated by the reticuloendothelial system. The drug shows linear pharmacokinetics, and its clearance is influenced by the dose administered. Filgrastim is not metabolized by the liver, and renal impairment does not significantly affect its clearance.

Contra-indications

• Hypersensitivity to filgrastim or any component of the formulation
• Sickle cell disease (in patients with this condition, filgrastim may increase the risk of sickle cell crisis)

Adverse effects

• Bone pain
• Fatigue
• Nausea
• Vomiting
• Headache
• Splenomegaly
• Increased levels of alkaline phosphatase
• Leukocytosis (increased white blood cell count)

Interactions

• Chemotherapy agents (may be used concurrently with caution, as filgrastim can affect the pharmacodynamics of certain chemotherapy drugs)
• Other hematopoietic growth factors (concurrent use may lead to increased effects and side effects)

Precautions

• Use with caution in patients with pre-existing bone marrow hyperactivity
• Monitor for signs of splenic rupture, especially if the patient presents with left upper abdominal pain
• Assess for potential allergic reactions
• Careful monitoring is recommended in patients with a history of respiratory disease

Pregnancy

Filgrastim is categorized as a pregnancy category C drug. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether filgrastim is excreted in human milk. Caution should be exercised when administering to breastfeeding women.

Storage

Store in a refrigerator (2-8 degrees Celsius). Do not freeze. Protect from light.

Formulations

• Injectable solution (various concentrations available for subcutaneous or intravenous administration)