Metastatic Breast Cancer: Eribulin Mesylate is indicated for the treatment of patients with metastatic breast cancer who have previously received at least two chemotherapy regimens for metastatic disease. Previous treatments should have included both an anthracycline and a taxane, either in the adjuvant setting or for metastatic disease.

Liposarcoma: Eribulin Mesylate is also indicated for patients with unresectable or metastatic liposarcoma who have previously been treated with a chemotherapy regimen containing an anthracycline.

Eribulin Mesylate is a microtubule dynamics inhibitor that interferes with the growth phase of microtubules while having minimal effect on the shortening phase. It binds to tubulin and causes the formation of nonproductive tubulin aggregates, which disrupt normal microtubule function. Through this tubulin-mediated antimitotic mechanism, eribulin blocks the G2/M phase of the cell cycle, disrupts mitotic spindle formation, and ultimately leads to programmed cancer cell death (apoptosis) following prolonged mitotic arrest. In laboratory studies involving human breast cancer cells, eribulin treatment resulted in changes in cell shape and gene expression, along with reduced cell migration and invasiveness. In mouse xenograft models of human breast cancer, eribulin therapy improved blood flow and permeability within tumors, reducing tumor hypoxia and altering gene expression associated with tumor phenotype changes.

The recommended dose of Eribulin is 1.4 mg/m² administered intravenously over 2 to 5 minutes on Days 1 and 8 of a 21-day cycle.

The recommended dose of Eribulin in patients with mild hepatic impairment (Child-Pugh A) is 1.1 mg/m² administered intravenously over 2 to 5 minutes on Days 1 and 8 of a 21-day cycle.

The recommended dose of Eribulin in patients with moderate hepatic impairment (Child-Pugh B) is 0.7 mg/m² administered intravenously over 2 to 5 minutes on Days 1 and 8 of a 21-day cycle.

The recommended dose of Eribulin in patients with moderate or severe renal impairment (creatinine clearance (CLcr) 15–49 mL/min) is 1.1 mg/m² administered intravenously over 2 to 5 minutes on Days 1 and 8 of a 21-day cycle.

Pediatric Use: The safety and effectiveness of HALAVEN in pediatric patients have not been established.

Effects of Other Drugs on Eribulin: Drug interaction studies indicate that Eribulin Mesylate is unlikely to have significant interactions with CYP3A4 inhibitors, CYP3A4 inducers, or P-glycoprotein (P-gp) inhibitors. Clinical studies in patients with advanced solid tumors showed no meaningful changes in drug exposure (AUC) when Eribulin was administered with ketoconazole (a strong CYP3A4 inhibitor and P-gp inhibitor) or with rifampin (a CYP3A4 inducer).

Effects of Eribulin on Other Drugs: At clinically relevant concentrations, Eribulin does not significantly inhibit or induce major cytochrome P450 enzymes, including CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4. Therefore, Eribulin is not expected to significantly affect the plasma levels of drugs metabolized by these enzymes.

The most commonly reported adverse reactions (≥25%) in metastatic breast cancer include neutropenia, anemia, asthenia/fatigue, alopecia, peripheral neuropathy, nausea, and constipation.

The most commonly reported adverse reactions (≥25%) in liposarcoma and leiomyosarcoma include fatigue, nausea, alopecia, constipation, peripheral neuropathy, abdominal pain, and pyrexia. The most common Grade 3–4 laboratory abnormalities (≥5%) in liposarcoma and leiomyosarcoma include neutropenia, hypokalemia, and hypocalcemia.

Based on findings from animal studies and its mechanism of action, Eribulin Mesylate may cause fetal harm if administered during pregnancy. There are no adequate data regarding the use of eribulin in pregnant women. It is not known whether eribulin or its metabolites are excreted in human breast milk, nor are the effects on breastfed infants or milk production known. Animal lactation studies have not been conducted.

Neutropenia: Peripheral blood cell counts should be regularly monitored, and the dosage may need adjustment if severe neutropenia occurs.

Peripheral Neuropathy: Patients should be monitored for symptoms of nerve damage, such as numbness or tingling. Dose delays or adjustments may be required.

Embryo-Fetal Toxicity: Eribulin may harm an unborn baby. Women of reproductive potential should use effective contraception during treatment.

QT Interval Prolongation: Caution is advised in patients with heart failure, slow heart rhythms, electrolyte imbalances, or those taking QT-prolonging drugs. Eribulin should be avoided in patients with congenital long QT syndrome.

Cytotoxic Chemotherapy

Store Eribulin Mesylate at 25°C. Temperature excursions between 15°C and 30°C are permitted. Do not freeze or refrigerate. Keep the vials in their original cartons.