- Class: Microtubule dynamics inhibitor – non-taxane microtubule inhibitor
- Type: IV cytotoxic chemotherapy
Mechanism of Action (MOA)
- Synthetic analog of halichondrin B (natural product from marine sponge).
- Binds to microtubule plus ends, inhibiting polymerization.
- Leads to mitotic blockade at G2/M phase → apoptosis.
- Distinct from taxanes – does not stabilize microtubules but prevents elongation.
Clinical Uses
- Metastatic breast cancer – previously treated with at least 2 chemotherapeutic regimens, including anthracyclines and taxanes.
- Liposarcoma – unresectable or metastatic (soft tissue sarcoma).
Dosing (Adults)
- 1.4 mg/m² IV over 2–5 minutes on days 1 and 8 of a 21-day cycle.
- Dose adjustments:
- Hepatic impairment
- Severe neutropenia or thrombocytopenia
- No routine premedication; antiemetics as needed.
Toxicities
- Hematologic: neutropenia (dose-limiting), anemia, thrombocytopenia
- Neurologic: peripheral neuropathy (sensory, cumulative)
- Fatigue, alopecia
- Gastrointestinal: nausea, constipation
- Rare: febrile neutropenia, QT prolongation
Monitoring
- CBC prior to each dose
- Neurologic assessment for peripheral neuropathy
- Liver function tests
- ECG if patient at risk of QT prolongation
- Monitor for signs of infection
Summary
Eribulin (Halaven®) is a non-taxane microtubule inhibitor used in heavily pretreated metastatic breast cancer and liposarcoma. Key concerns are myelosuppression, peripheral neuropathy, and fatigue, requiring CBC monitoring, neurologic assessment, and liver function monitoring.