II. Indications
- FDA Approved (in combination regimens)
- Mesothelioma (malignant, pleural)
- Non-Small Cell Lung Cancer (non-squamous cell)
- Off-Label Use
- Bladder Cancer (metastatic)
- Cervical Cancer
- Ovarian Cancer (resistant)
- Thymic Cancer
III. Contraindications
- Children
- Creatinine Clearance <45 ml/min
IV. Mechanism
- Pemetrexed is a synthetic Pyrimidine-based antifolate agent, similar to Methotrexate
- Pemetrexed binds the enzyme thymidylate synthase (TS), blocking its activity
- Inhibits methylation of dUMP to dTMP
- Inhibits DNA synthesis
V. Medications
- Pemetrexed powder for IV Solution: Available in 100 mg and 500 mg vials
VI. Dosing
- See other references for disease specific dosing protocols
- Coadministered agents to reduce adverse effects
- Folic Acid 400 to 1000 mcg orally daily for 21 days (after last dose)
- Vitamin B12 1000 mcg IM every 3 Pemetrexed cycles
- Dexamethasone 4 mg orally twice daily for 3 days starting on the day prior to treatment
VII. Adverse Effects
- Myelosuppression
- Rash
- Decreased with Dexamethasone (see dosing above)
VIII. Safety
- Avoid in Pregnancy (any trimester)
- Use reliable Contraception
- Avoid in Lactation
- Monitoring
IX. Drug Interactions
-
NSAIDs
- Avoid coadministering at time of Pemetrexed infusion