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.

Further information

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

Medical Disclaimer