Margetuximab Dosage

Medically reviewed by Drugs.com. Last updated on Apr 10, 2025.

Usual Adult Dose for Breast Cancer

15 mg/kg IV every 3 weeks

Comment:

• Infuse initial dose over 120 minutes and subsequent doses over 30 minutes.
• This drug may be administered immediately after the completion of chemotherapy.
• Continue treatment until disease progression or unacceptable toxicity.
• All therapeutic proteins, including this drug, have the potential to produce an immune response.

Use: In combination with chemotherapy, for the treatment of adult patients with metastatic HER2-positive breast cancer who have received two or more prior anti-HER2 regimens, at least one of which was for metastatic disease

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available

Dose Adjustments

LEFT VENTRICULAR EJECTION FRACTION (LVEF):
Withhold dosing for at least 4 weeks for any of the following:

• If 16% or greater absolute decrease in LVEF from pretreatment values.
• LVEF below institutional limits of normal or 50% if no limits are available.
• If 10% or greater absolute decrease in LVEF from pretreatment values
• The dosing may be resumed if, within 8 weeks, LVEF returns to normal limits, and a total reduction from baseline is 15% or less.
• Permanently discontinue if LVEF decline persists for greater than 8 weeks or if dosing is interrupted on greater than 3 occasions for LVEF decline.

INFUSION-RELATED REACTIONS (IRRs):

• For mild or moderate IRRs, decrease the rate of infusion.
• For dyspnea or clinically significant hypotension, interrupt the infusion.
• For patients with severe or life-threatening IRRs, permanently discontinue treatment.

Precautions

US BOXED WARNINGS:

• LEFT VENTRICULAR DYSFUNCTION: This drug may lead to reductions in left ventricular ejection fraction (LVEF). Evaluate cardiac function prior to and during treatment. Discontinue treatment for a confirmed a clinically significant decrease in left ventricular function.
• EMBRYO-FETAL TOXICITY: Exposure to this drug during pregnancy can cause embryofetal harm. Advise patients of the risk and need for effective contraception.

CONTRAINDICATIONS:

• None

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• Administer as an IV infusion after dilution.
• Infuse initial dose over 120 minutes and subsequent doses over 30 minutes.
• This drug may be administered immediately after the completion of chemotherapy.
• Do not administer as an IV push or bolus.
• Do not mix this drug with other drugs.
• Do not co-administer other drugs through the same infusion line.
• If a patient misses a dose, administer the scheduled dose as soon as possible, and then adjust the administration schedule to maintain a 3-week interval between doses.

Storage Requirements:

• Store vials refrigerated at 2C to 8C (36F to 46F) in the original carton to protect from light.
• Do not freeze.
• Do not shake.

Reconstitution/preparation techniques:

• The manufacturer product information should be consulted.

Monitoring:

• Cardiovascular: Left ventricular dysfunction by echocardiogram or MUGA scan.
• Immunologic: Monitor or sign and symptoms for infusion-related reactions.
• Pregnancy: Monitor females who received this drug for oligohydramnios during pregnancy or within 4 months prior to conception.

Patient advice:

• Advise pregnant women and females of reproductive potential that exposure to this drug during pregnancy or within 4 months prior to conception can result in fetal harm.
• Advise females of reproductive potential to use effective contraception during treatment and 4 months after the last dose.
• Advise female patients to contact their healthcare provider with a known or suspected pregnancy.
• Advise patients to report immediately any new onset or worsening shortness of breath, cough, swelling of the ankles/legs, swelling of the face, palpitations, weight gain of more than 5 pounds in 24 hours, dizziness, or loss of consciousness.

See also:

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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