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Understanding Treatment

Starting HERZUMA

Questions and answers about starting HERZUMA

WHAT you should tell your doctor before starting HERZUMA

Before receiving HERZUMA, tell your doctor if you:

  • Have trouble with your heart. HERZUMA can cause heart problems in some patients
  • Are pregnant or plan to become pregnant. Trastuzumab products can cause fetal harm when administered to a pregnant woman. Because trastuzumab stays in the body for a long time, you should avoid becoming pregnant for 7 months after discontinuing HERZUMA
  • Are taking any other medications, including prescription and over-the-counter medicines, vitamins, and herbal supplements

Know the medicines you take. Keep a list of them to show to your doctor and pharmacist when you get a new medicine. Do not take any new medicine without speaking with your doctor.


Your healthcare team will monitor your heart for potential cardiac issues to detect them early on so they can be properly treated.

Your heart will be monitored at the start of treatment, every 3 months while on HERZUMA therapy, and every 6 months for at least 2 years following completion of HERZUMA as a component of adjuvant therapy. Heart function will be tested with an ECHO* or MUGA scan.

*ECHO scan is an ultrasound image of the heart.

MUGA scan takes a moving picture of your heart pumping blood following an injection of a nontoxic radioactive substance.

During HERZUMA therapy

  • Pausing HERZUMA
    • In case of reduced heart function, your doctor may hold HERZUMA therapy up to 3 times
  • Restarting HERZUMA
    • Your doctor may restart HERZUMA therapy up to 3 times if your heart function improves and returns to normal limits after HERZUMA has been held
  • Discontinuing HERZUMA
    • HERZUMA will be discontinued if you experience congestive heart failure (CHF) or significantly reduced heart function (when the heart can’t keep up with the amount of blood flowing through it)

After HERZUMA therapy

  • Your heart should be monitored every 6 months for at least 2 years


  • HERZUMA is given by infusion through a needle placed in a vein (intravenous infusion) in your arm, or through a port
  • Talk to your doctor to find out whether you will receive HERZUMA in an infusion center or in your doctor's office
  • The first dose of HERZUMA takes about 90 minutes. After that, the other doses of HERZUMA only take about 30 minutes


  • Your healthcare provider may prescribe medicines before each infusion of HERZUMA to reduce infusion side effects such as fever and chills
  • Taking the suggested medication before treatment may reduce the chance of having a severe reaction during the first HERZUMA infusion
  • Be sure to ask your doctor or nurse about what you should take before HERZUMA treatment


  • Your doctor should do blood tests and monitor your heart regularly to check for side effects to HERZUMA
  • Before each HERZUMA treatment, your healthcare provider will ask you questions about your general health. Tell your healthcare provider about any new symptoms


5 things to help prepare yourself before every infusion:

  • Plan Transportation To and From Your Infusion Appointment

    You may feel exhausted after your infusion, so having someone else drive you home after treatments is a good idea.

  • Bring Something To Pass the Time

    A day at the clinic can be long. Reading magazines, completing a word search, or enjoying a similar activity can help you occupy the time.

  • Bring Food and Beverages

    You may be at the clinic for most of the day, so pack some snacks or a light meal and bring a water bottle.

  • Tell Your Doctor or Nurse About Medicines You Are Taking

    If you take any other medicines, tell your doctor or nurse. Do not start any new medications without talking to your doctor. Your doctor may give you special instructions for your infusion day.

  • Speak Up

    Tell your doctor or nurse about any concerns you have.

Looking to save on the cost of HERZUMA?

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Patients are selected for therapy with HERZUMA based on an FDA-approved test.

Adjuvant Breast Cancer

HERZUMA is a prescription medicine used for the treatment of early-stage breast cancer that is Human Epidermal growth factor Receptor 2-positive (HER2+) and has spread into the lymph nodes, or is HER2-positive and has not spread into the lymph nodes. If it has not spread into the lymph nodes, the cancer needs to be estrogen receptor/progesterone receptor (ER/PR)-negative or have one high-risk feature. HERZUMA can be used in several different ways:

  • As part of a treatment course including the chemotherapy drugs doxorubicin, cyclophosphamide, and either paclitaxel or docetaxel. This treatment course is known as “AC TH”
  • With the chemotherapy drugs docetaxel and carboplatin. This treatment course is known as “TCH”
  • Alone after treatment with multiple other therapies, including an anthracycline (doxorubicin)-based therapy (a type of chemotherapy)

Patients are selected for therapy with HERZUMA based on an FDA-approved test.

Metastatic Breast Cancer

HERZUMA has 2 approved uses in metastatic breast cancer:

  • HERZUMA in combination with the chemotherapy drug paclitaxel is approved for the first-line treatment of Human Epidermal growth factor Receptor 2-positive (HER2+) metastatic breast cancer
  • HERZUMA alone is approved for the treatment of HER2-positive breast cancer in patients who have received one or more chemotherapy courses for metastatic disease

Patients are selected for therapy with HERZUMA based on an FDA-approved test.


HERZUMA can cause serious side effects, including:

  • HEART PROBLEMS: Trastuzumab products can cause heart problems—such as congestive heart failure or reduced heart function—with or without symptoms. The risk for and seriousness of these heart problems were highest in people who received both a trastuzumab product and a certain type of chemotherapy (anthracycline). In a study of adjuvant (early) breast cancer, one patient died of significantly weakened heart muscle. Your healthcare provider will check for signs of heart problems before, during, and after treatment with HERZUMA
  • INFUSION REACTIONS: Infusion reactions, sometimes serious or fatal, have occurred. Symptoms may include: fever, chills, feeling sick to your stomach (nausea), throwing up (vomiting), pain (in some cases at tumor site), headache, dizziness, and shortness of breath. These symptoms usually happen within 24 hours after receiving HERZUMA
  • SEVERE LUNG PROBLEMS: Trastuzumab product use can result in serious and fatal lung problems. Symptoms may include: severe shortness of breath, fluid in or around the lungs, weakening of the valve between the heart and lungs, not enough oxygen in the body, swelling of the lungs, and scarring of the lungs. Your healthcare provider may check for signs of severe lung problems
  • HARM TO UNBORN BABIES OR BIRTH DEFECTS: Trastuzumab products may result in birth defects or the death of an unborn baby. Contraception should be used while receiving HERZUMA and for 7 months after your last dose of HERZUMA. If you are or become pregnant while receiving HERZUMA or within 7 months after your last dose of HERZUMA, you should immediately contact your doctor. Patients should contact their healthcare professional with a known or suspected pregnancy
  • LOW WHITE BLOOD CELL COUNTS: Low white blood cell counts (which may be life-threatening) were seen more often in patients receiving trastuzumab plus chemotherapy than in patients receiving chemotherapy alone. Your healthcare provider may check for signs of low white blood cell counts

Your healthcare provider will stop treatment with HERZUMA if you have severe, serious, or life-threatening side effects.

The most common side effects for patients receiving HERZUMA for breast cancer include: headache, diarrhea, feeling sick to your stomach (nausea), chills, fever, infection, weakened heart muscle, unable to sleep, cough, and rash.

These are not all of the possible side effects with HERZUMA. Talk to your doctor about any side effects you may experience.

Please see full Prescribing Information, including BOXED WARNINGS.

You may report side effects to the FDA at (800) FDA-1088 or

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