Drug Guide
Pegaspargase
Classification
Therapeutic: Antineoplastic agent
Pharmacological: Enzyme, L-asparaginase
FDA Approved Indications
- Acute lymphoblastic leukemia (ALL) in patients who have received prior therapy including asparaginase
Mechanism of Action
Pegaspargase depletes asparagine, an amino acid necessary for the survival of leukemia cells; it catalyzes the hydrolysis of asparagine to aspartic acid and ammonia, depriving cancer cells of an essential amino acid.
Dosage and Administration
Adult: Dose varies; typically 2,500 units/m^2 once every 14 days, administered intravenously or intramuscularly.
Pediatric: Dose varies based on body surface area; administered every 14 days.
Geriatric: Use with caution; no specific dose adjustments established.
Renal Impairment: No specific adjustments; monitor closely.
Hepatic Impairment: Use with caution; no specific adjustments established.
Pharmacokinetics
Absorption: Administered parenterally; absorption data not applicable.
Distribution: Widely distributed, including into cerebrospinal fluid and tissues.
Metabolism: Metabolized in the blood and tissues; cleared via hepatic routes.
Excretion: Excreted primarily through the hepatic system.
Half Life: Approximately 5.7 days (variable).
Contraindications
- History of severe hypersensitivity to pegaspargase or other asparaginases
Precautions
- Risk of allergic reactions, including anaphylaxis
- Pancreatitis, hepatotoxicity, thrombosis, bleeding, and coagulopathy
- Monitor for hypersensitivity reactions especially during and after infusion
Adverse Reactions - Common
- Nausea, vomiting (Common)
- hypersensitivity reactions, including anaphylaxis (Uncommon)
- Pancreatitis (Uncommon)
Adverse Reactions - Serious
- Hypersensitivity reactions including anaphylaxis (Rare)
- Pancreatitis leading to severe complications (Rare)
- Hepatotoxicity with liver failure (Rare)
- Thrombosis and coagulopathy (Rare)
- Neurotoxicity (Rare)
Drug-Drug Interactions
- Other chemotherapeutic agents, especially methotrexate, potentially increasing toxicity
Drug-Food Interactions
- No significant food interactions reported
Drug-Herb Interactions
- No well-established interactions
Nursing Implications
Assessment: Monitor for hypersensitivity reactions, signs of bleeding, signs of pancreatitis, liver function, coagulation parameters.
Diagnoses:
- Risk for allergic reaction, Risk for bleeding, Risk for pancreatitis
Implementation: Administer as ordered; premedicate if necessary; monitor vital signs during infusion; have emergency equipment available.
Evaluation: Assess for adverse reactions, treatment response, and signs of toxicity.
Patient/Family Teaching
- Report any allergic reactions, difficulty breathing, swelling, or rash immediately.
- Inform about possible side effects such as nausea, pancreatitis symptoms, and signs of bleeding.
- Follow schedule for doses and attend all follow-up appointments.
Special Considerations
Black Box Warnings:
- Serious allergic reactions including anaphylaxis, serum sickness, and severe hypersensitivity
- Pancreatitis leading to death or severe long-term sequelae
Genetic Factors: No specific genetic testing recommended before use.
Lab Test Interference: May interfere with blood clotting tests, causing false readings.
Overdose Management
Signs/Symptoms: Allergic reactions, hypersensitivity, pancreatitis, bleeding disorders.
Treatment: Discontinue drug immediately; provide supportive care including antihistamines, corticosteroids, fluids; manage adverse effects as required.
Storage and Handling
Storage: Store at 2°C to 8°C (36°F to 46°F). Do not freeze.
Stability: Stable when refrigerated; protect from light.