Ixabepilone, Ixempra

  • Indications
  1. Breast Cancer (locally advanced or metastatic)
  • Contraindications
  1. Liver transaminases (AST, ALT) >2.5 times the upper limit of normal
  2. Serum Bilirubin > upper limit of normal
  3. Polyoxyethylated Castor Oil (Cremophor EL) allergy
  • Mechanism
  1. See Mitotic Inhibitor Chemotherapy
  2. Ixabepilone is a semisynthetic analog of epothilone B with antineoplastic properties
    1. Used in Taxane-resistant neoplasms
    2. Available in an enteric coated oral formulation with good Bioavailability
  3. Ixabepilone is an anti-tubulin agent
    1. Ixabepilone binds to tubulin
    2. Ixabepilone promotes tubulin polymerization and microtubule stabilization
    3. Arrests cell cycle at G2/M phase
  • Medications
  1. Ixabepilone 15 and 45 mg powder for injection
  • Dosing
  1. See other references for disease specific dosing protocols
  2. Pretreatment (given 1 hour before Ixabepilone )
    1. Anthistamine (H1 Blocker) AND
    2. H2 Blocker (e.g. Famotidine) AND
    3. If prior reaction, Corticosteroid
  • Safety
  1. Avoid in Lactation
  2. Avoid in pregnancy (all trimesters)
    1. Use reliable Contraception
  • Drug Interactions
  1. Agents that increase Ixabepilone levels
    1. CYP3A4 Inhibitors (e.g. Ketoconazole)
  2. Agents that decrease Ixabepilone levels
    1. CYP3A4 Inducers (e.g. Rifampin)