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Herceptin

trastuzumab
Used for Breast Cancer, Stomach Cancer
Used for Breast Cancer, Stomach Cancer

Herceptin (trastuzumab) is a targeted anticancer treatment for certain HER2-positive cancers. It treats HER2-positive, early-stage, breast cancer (after breast surgery to remove the tumor) and late-stage, metastatic breast cancer (spread to other parts of the body). It can also treat HER2-positive, metastatic stomach cancer. Herceptin (trastuzumab) is most often used together with other anticancer medications, but can also be used by itself. Depending on the type of cancer, Herceptin (trastuzumab) can be injected into a vein (intravenous, IV) or under the skin (subcutaneous, SQ).

Last reviewed on October 5, 2022
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What is Herceptin (trastuzumab)?

What is Herceptin (trastuzumab) used for?

  • HER2-positive, breast cancers - IV and SQ injections

  • HER2-positive, metastatic stomach cancer - IV injection only

How Herceptin (trastuzumab) works

Herceptin (trastuzumab) is a monoclonal antibody that acts as a human epidermal growth factor receptor 2 (HER2) inhibitor. It blocks a specific protein in the body that’s important for cell growth called HER2. HER2 is found on both normal and cancer cells. Cancer cells usually have more HER2 proteins than normal cells. This can cause cancer cells to grow more quickly than normal cells. When HER2 is blocked by Herceptin (trastuzumab), cancer cells can’t grow and spread as well.

Are you looking for information on Kadcyla (ado-trastuzumab emtansine) or Enhertu (fam-trastuzumab deruxtecan) instead?

Drug Facts

Drug ClassHER2 receptor antagonist
Controlled Substance ClassificationNot a controlled medication
Generic StatusNo lower-cost generic available
AvailabilityPrescription only
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What are the side effects of Herceptin (trastuzumab)?

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

  • Body and joint pain (up to 47%)
  • Weakness (up to 42%)
  • Fever (up to 36%)
  • Nausea (to up 33%)
  • Chills (up to 32%)
  • Headache (up to 26%)
  • Cough (up to 26%)
  • Diarrhea (up to 25%)
  • Vomiting (up to 23%)
  • Infection (up to 20%)
^*Side effect percentages listed for Herceptin (trastuzumab) when used by itself.^

Other Side Effects

  • Dizziness
  • Sore throat or runny nose
  • Loss of appetite
  • Trouble sleeping
  • Swelling of the legs or arms
  • Rash

Serious Side Effects

Contact your healthcare provider immediately if you experience any of the following.
  • Heart problems: chest pain, racing heartbeat, shortness of breath that usually worsens with activity or while lying flat, swelling of your legs or feet, sudden weight gain, fatigue
  • Serious infusion reactions: trouble breathing, itching or hives, flushing, swelling, chest pain, fast heartbeat, dizziness, fainting
  • Lung problems: shortness of breath, trouble breathing
  • Serious infections (when receiving in combination with chemotherapy): repeated fevers, chills, sweating, cough, trouble breathing, severe diarrhea, vomiting, painful or frequent urination

Source: DailyMed

The following side effects have also been reported

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur:

More common

Dizziness

fever or chills

headache

muscle aches

nausea or vomiting

skin rash

sore throat

stuffy or runny nose

unusual tiredness or weakness

Less common

Bloody nose

cough

diarrhea

difficult or labored breathing

ear congestion or pain

fast or irregular heartbeat

general feeling of discomfort or illness

head congestion

hoarseness or other voice changes

increased cough

joint pain

loss of appetite

nasal congestion

pain or tenderness around the eyes and cheekbones

shivering

sneezing

sweating

swelling of the feet or lower legs

tightness in the chest

trouble with sleeping

vomiting

Rare

Blue lips and fingernails

blurred vision

chest pain

confusion

cough or hoarseness, accompanied by fever or chills

faintness or lightheadedness when suddenly getting up from a lying or sitting position

itching

large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, feet, or sex organs

lower back or side pain, accompanied by fever or chills

painful or difficult urination, accompanied by fever or chills

pale skin

redness of the skin

Incidence not known

Black, tarry stools

bloody or cloudy urine

sores, ulcers, or white spots in the mouth

unusual bleeding or bruising

weight gain

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Difficulty in moving

metallic taste in the tongue

muscle pain or stiffness

pain

weight loss

Less common

Numbness or tingling of the hands or feet

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

pros-and-cons

Pros and cons of Herceptin (trastuzumab)

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Pros

Recommended treatment option for HER2-positive breast cancers and metastatic stomach cancer

More precise in the way it targets cancer cells compared to traditional chemotherapy

For breast cancers, can be given either as an injection under the skin or through a vein (IV), depending on preference

Short injection times (30 to 90 minutes IV; 2 to 5 minutes under the skin)

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Cons

Requires regular visits to the clinic or infusion center to receive your dose

Can cause heart failure or other heart problems and requires regular monitoring of heart function

Not safe during pregnancy since it can harm an unborn baby

pharmacist-tips

Pharmacist tips for Herceptin (trastuzumab)

pharmacist
  • Herceptin (trastuzumab) is only used to treat cancers that have high levels of the HER2 protein (HER2-positive). Your provider will first test a sample of your tumor to see if your cancer is HER2-positive before starting treatment.

    • You might experience a reaction during or shortly after your Herceptin (trastuzumab) infusion, which can be life-threatening. Let your provider know or get help right away if you experience any infusion reactions like trouble breathing, hives, flushing, chest pain, skin turning blue, fast heartbeat, or dizziness.

      • You can feel some discomfort or pain at the injection site when receiving Herceptin (trastuzumab), either through the vein (IV) or injected under the skin (subcutaneously). Let your provider know if this is bothersome so they can manage it appropriately.

        • You’ll need regular monitoring of your heart while receiving Herceptin (trastuzumab) and for a few years after your last dose. This is because Herceptin (trastuzumab) can cause heart failure and other heart problems. Make sure to let your provider know right away if you experience any new or worsening shortness of breath, cough, swelling of your legs or feet, sudden weight gain, racing heartbeat, dizziness, or fainting. These can be signs of heart failure and you might need to stop taking this medication.

          • If you’re a female who can get pregnant, you should use birth control while receiving Herceptin (trastuzumab) and for 7 months after the last dose. This medication can cause harm to an unborn baby. Let your provider know right away if you become pregnant during Herceptin (trastuzumab) treatment.

            faqs

            Frequently asked questions about Herceptin (trastuzumab)

            How common are HER2-positive cancers?
            In breast cancer, about 15% to 20% of tumors are HER2-positive. Similarly, in stomach cancer, about 20% (1 in 5) of tumors are HER2-positive. Having a tumor that’s HER2-positive means that your cancer cells have high levels of a protein called HER2 and can be treated with HER2-targeting medications like Herceptin (trastuzumab). Before starting treatment, your provider will first test a sample of your tumor to see if your cancer is HER2-positive and if Herceptin (trastuzumab) is an option for you.
            What’s the difference between Herceptin (trastuzumab) and Herceptin Hylecta (trastuzumab / hyaluronidase)?
            Herceptin (trastuzumab) is the IV form of trastuzumab that’s injected into the vein over 30 to 90 minutes. Herceptin Hylecta (trastuzumab / hyaluronidase) is the subcutaneous form of trastuzumab that’s given as an injection under the skin over 2 to 5 minutes. In addition to trastuzumab, it contains a protein called hyaluronidase, which helps your body absorb the medication better when injected under the skin. While Herceptin (trastuzumab) and Herceptin Hylecta are both used to treat HER2-positive breast cancers, Herceptin (trastuzumab) can also treat HER2-positive metastatic stomach cancer. Another difference is that the dose of Herceptin (trastuzumab) is based on your weight and is given either weekly or every 3 weeks, but Herceptin Hylecta is given as a flat dose every 3 weeks.
            Can I receive Herceptin (trastuzumab) again if I've had an infusion reaction before?
            Possibly. It depends on how severe your reaction was. Your provider should discuss with you about the risks and benefits of using Herceptin (trastuzumab) again after you’ve had an infusion reaction. There are a few things your provider can do to try to prevent future reactions or to lower their severity. Your provider can give you antihistamines or corticosteroids before future infusions. They can also slow down how fast you receive the infusion. But if your reaction is severe, you might not be able to use Herceptin (trastuzumab) again. Talk to your provider if you’re concerned about receiving this treatment.
            What are the biosimilars to Herceptin (trastuzumab)?
            Herzuma, Kanjinti, Ogivri, Ontruzant, and Trazimera are known as biosimilars to Herceptin (trastuzumab). A biosimilar is a biologic medication that has a comparable structure and works like the original biologic that was first approved by the FDA (Herceptin). Biosimilars are like generics, but they aren't exactly the same as the original medication. Biologics are made from living organisms such as animal cells or bacteria. Because of the complex way they're made, exact copies of the original medication can't be made.
            What’s the difference between Herceptin (trastuzumab), Herzuma, Kanjinti, Ogivri, Ontruzant, and Trazimera?
            Herzuma, Kanjinti, Ogivri, Ontruzant, and Trazimera are biosimilars to Herceptin (trastuzumab). All six brands are used to treat HER2-positive breast and stomach cancer, and they all have similar side effects. They can be used as substitutes for one another. Biosimilars might be available at a lower cost than Herceptin (trastuzumab). Your insurance may prefer to cover one brand over others.
            Is Herceptin (trastuzumab) safe while breastfeeding?
            There are no studies in humans to show the effects of this medication when breastfeeding. However, animal studies found Herceptin (trastuzumab) in the milk of lactating monkeys, so it's likely that this medication can be passed along in human breast milk. Because of this risk, you shouldn't breastfeed while receiving Herceptin (trastuzumab) unless your provider thinks the benefit is greater than the risk for both you and your baby. Talk with your provider if you have any questions about breastfeeding while receiving Herceptin (trastuzumab).
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            What are the risks and warnings for Herceptin (trastuzumab)?

            Herceptin (trastuzumab) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

            risk-warning

            Heart failure and other heart problems

            • Risk factors: Receiving Herceptin (trastuzumab) with other heart-damaging anticancer medications

              Herceptin (trastuzumab) can cause new or worsening heart failure and affect how well your heart pumps blood through your body. Your risk of heart problems is higher if you’re receiving Herceptin (trastuzumab) with other heart-damaging anticancer medications. Make sure your provider has your full medical history, so they can closely monitor your heart through imaging using an echocardiogram or a MUGA scan. You’ll need to get this scan before starting treatment, about every 3 months while receiving Herceptin (trastuzumab), and a few more times after you complete treatment. Let your care team know if you experience any signs and symptoms of heart failure, including shortness of breath, dry cough, irregular heartbeats, chest pain, or weight gain.

              risk-warning

              Infusion reactions

              Herceptin (trastuzumab) can cause infusion reactions, most commonly fever and chills. They can also include nausea, vomiting, pain, headache, dizziness, rash, and weakness. These reactions are usually mild and tolerable, but in rare cases, they can be serious. They can also happen during or several hours after the infusions. Alert your provider or get medical help right away if you experience any throat tightness, trouble breathing, fast heartbeat, fever, chills, hives, flushing, dizziness, or chest pain.

              risk-warning

              Lung problems

              • Risk factors: History of lung problems | Cancer tumors in the lung

                Rare, but serious, lung problems, including inflammation of the lungs and fluid buildup in the lungs, have happened in people receiving Herceptin (trastuzumab). This can be related to signs of an infusion reaction. Let your provider know if you have difficulty breathing, cough, or fatigue during your treatment.

                risk-warning

                Harm to unborn baby

                Herceptin (trastuzumab) can harm an unborn baby. This medication can affect the amount of amniotic fluid surrounding your baby in the womb. This can potentially cause developmental abnormalities and even death. Because of this risk, if you’re a female who can get pregnant, you should use birth control while receiving Herceptin (trastuzumab) and for 7 months after the last dose. Let your provider know right away if you become pregnant during this time.

                risk-warning

                Low blood counts when used with chemotherapy

                In studies, people receiving Herceptin (trastuzumab) in combination with bone marrow-suppressing chemotherapy had more serious decreases in their white blood cell, red blood cell, and platelet levels compared to those receiving chemotherapy alone. This raises the risk of developing infections and bleeding or bruising. Let your provider know as soon as possible if you experience fevers, chills, or bleeding and bruising that doesn’t stop or go away. You might need to stop this medication.

                dosage

                Herceptin (trastuzumab) dosage forms

                Typical dosing for Herceptin (trastuzumab)

                Herceptin (trastuzumab) is given by a healthcare provider as an injection into a vein (IV) or as an injection under the skin (subcutaneous, SQ).

                When given IV, the dose depends on your body weight. Your healthcare provider will determine the appropriate dose for you each time you receive the medication.

                HER2-positive, breast cancers

                • IV injection: The typical dose is 4 mg/kg of bodyweight IV for the first injection, and then 2 mg/kg given once a week. It can also be given as 8 mg/kg for the first injection, and then 6 mg/kg every 3 weeks thereafter.

                • SQ injection (Herceptin Hylecta brand only): Herceptin Hylecta for injection under the skin contains trastuzumab and hyaluronidase. The typical dose is 600 mg/10,000 units (trastuzumab/hyaluronidase) given under the skin every 3 weeks. The SQ injection is a flat dose and isn’t dependent on weight.

                HER2-positive, metastatic stomach cancer: The typical dose is 8 mg/kg IV for the first injection, and then 6 mg/kg every 3 weeks thereafter.

                interactions

                Interactions between Herceptin (trastuzumab) and other drugs

                Herceptin (trastuzumab) may interact with certain medications or supplements. Always let your doctor and pharmacist know about any other medications or supplements (including prescribed and over-the-counter medications, vitamins, and dietary or herbal supplements) that you are currently taking. The list below does not include all possible drug interactions with Herceptin (trastuzumab). Please note that only the generic name of each medication is listed below.

                Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

                Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

                Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

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