Nurses Compass
Drug Guide
Ixabepilone
Classification
Therapeutic: Antineoplastic agent
Pharmacological: Epothilone, microtubule inhibitor
FDA Approved Indications
- Locally advanced or metastatic breast cancer that is hormone-receptor negative or has been previously treated with anthracyclines, taxanes, and chemotherapy
Mechanism of Action
Ixabepilone stabilizes microtubules and inhibits their disassembly, disrupting cell division and leading to apoptosis in cancer cells.
Dosage and Administration
Adult: 40 mg/m² IV over 3 hours every 21 days, with premedication to prevent hypersensitivity reactions.
Pediatric: Not established.
Geriatric: Use with caution; consider renal and hepatic function.
Renal Impairment: Adjust dose based on renal function; specific guidelines not established.
Hepatic Impairment: Adjust dose; contraindicated in severe hepatic impairment.
Pharmacokinetics
Absorption: Administered intravenously; no oral absorption data.
Distribution: Vd approximately 6-10 L/kg.
Metabolism: Primarily hepatic via CYP3A4; minor pathways include CYP2C8 and CYP2C9.
Excretion: Mostly biliary/fecal; minimal renal excretion.
Half Life: Approximately 52 hours.
Contraindications
- Hypersensitivity to ixabepilone or any component of the formulation.
Precautions
- Evaluate for hypersensitivity reactions; monitor liver function; use with caution in patients with pre-existing hepatic impairment, CNS metastases, or peripheral neuropathy.
Adverse Reactions - Common
- Neutropenia (Very common)
- Peripheral neuropathy (Common)
- Fatigue (Common)
- Nausea (Common)
Adverse Reactions - Serious
- Septic shock or severe infections (Rare)
- Severe hypersensitivity reactions (Rare)
Drug-Drug Interactions
- CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin) may increase ixabepilone levels, increasing toxicity.
- CYP3A4 inducers (e.g., rifampin) may decrease efficacy.
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Monitor blood counts closely; assess for signs of infection, neuropathy, and hypersensitivity reactions.
Diagnoses:
- Imbalanced nutrition: less than body requirements due to nausea or mucositis.
- Risk for fracture due to peripheral neuropathy.
Implementation: Administer premedications as prescribed; monitor infusion site for reactions; manage side effects during therapy.
Evaluation: Monitor blood counts, neurologic status, and patient tolerance to therapy.
Patient/Family Teaching
- Report signs of allergic reactions immediately.
- Use effective contraception during and for 6 months after therapy.
- Report any signs of infection, neuropathy, or unusual bleeding.
Special Considerations
Black Box Warnings:
- Myelosuppression (neutropenia, thrombocytopenia) can be severe and occasionally fatal.
- Severe hypersensitivity reactions may occur.
Genetic Factors: No specific genetic considerations identified.
Lab Test Interference: May affect liver function tests and blood counts.
Overdose Management
Signs/Symptoms: Severe neutropenia, peripheral neuropathy, hypersensitivity reactions.
Treatment: Supportive care; discontinue drug; treat symptoms; consider use of corticosteroids for allergic reactions; no specific antidote.
Storage and Handling
Storage: Store in a refrigerator (2°C to 8°C). Protect from light.
Stability: Stable for 24 hours at room temperature after reconstitution; refrigerate unused portions.