Neulasta (Pegfilgrastim)

Neulasta (pegfilgrastim) is a granulocyte colony‑stimulating factor used to support patients undergoing myelosuppressive chemotherapy.

• Chemotherapy‑induced neutropenia: reduces the duration and severity of neutropenia in patients receiving myelosuppressive chemotherapy.
• Peripheral blood stem cell mobilization: facilitates collection of stem cells for autologous transplantation.
• Hematopoietic recovery after high‑dose chemotherapy: accelerates neutrophil recovery to lower infection risk.

• Pegfilgrastim binds with high affinity to the G‑CSF receptor on hematopoietic progenitor cells in the bone marrow. This interaction triggers intracellular signaling pathways that promote proliferation, differentiation, and activation of neutrophil precursors, leading to increased circulating neutrophil counts and shortened periods of chemotherapy‑induced neutropenia.

Common Side Effects

• Bone pain: mild to moderate discomfort often reported after injection.
• Injection site reactions: redness, swelling, or tenderness at the administration site.
• Fatigue: transient feeling of tiredness.
• Nausea: occasional upset stomach.
• Headache: mild headache may occur.

Serious or Rare Side Effects

• Severe allergic reactions: anaphylaxis, angioedema, or rash requiring immediate medical attention.
• Splenic rupture: rare but potentially life‑threatening abdominal emergency.
• Acute respiratory distress syndrome (ARDS): severe breathing difficulty.
• Capillary leak syndrome: sudden drop in blood pressure and fluid accumulation.
• Leukocytosis: excessively high white blood cell counts.

Neulasta should be used under close medical supervision with attention to patient‑specific factors.

• Dose adjustment: follow prescriber instructions based on chemotherapy regimen and patient characteristics.
• Renal impairment: monitor patients with severe renal dysfunction, as clearance may be altered.
• Bone pain management: assess and treat pain proactively, especially after the first dose.
• Allergic reactions: discontinue immediately if signs of hypersensitivity appear.
• Concomitant myeloid growth factors: avoid simultaneous use to prevent overlapping effects.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Pegfilgrastim may interact with other agents that affect bone marrow or immune function.

Major Interactions (Avoid)

• Concurrent use with other myeloid growth factors: may increase risk of bone marrow suppression.
• Live vaccines: may reduce vaccine efficacy; avoid administration during treatment.

Moderate Interactions (Monitor Closely)

• Cytotoxic chemotherapy: timing must be coordinated to avoid reduced chemotherapy efficacy.
• Antibiotics that affect neutrophil function: monitor blood counts for additive effects.
• Corticosteroids: may mask signs of infection; observe patients closely.