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Hercessi

Pronunciation: HER-sess-ee
Generic name: trastuzumab-strf
Dosage form: single-dose vial for intravenous infusion
Drug class: HER2 inhibitors

Medically reviewed by Carmen Pope, BPharm. Last updated on Apr 29, 2024.

What is Hercessi?

Hercessi (trastuzumab-strf) is a biosimilar to Herceptin that is given by intravenous infusion and may be used to treat certain types of HER2+ (Human Epidermal Growth Factor Receptor 2-Positive) cancers, specifically:

Patients are deemed eligible for treatment following an FDA-approved companion diagnostic for trastuzumab.

Hercessi is a targeted treatment, not chemotherapy, because it targets cancers that have large amounts of receptor proteins called HER2. HER2 is thought to send signals to cells telling them to grow and divide rapidly, causing tumors to form. By targeting and attaching to these receptors, Hercessi is thought to inhibit the growth and cell division of human tumor cells that overexpress HER2 and also tell the body’s immune system to destroy the cell. Normal cells also have HER2, but less of it, so Hercessi can affect normal cells, causing side effects.

Hercessi was approved as a biosimilar to Herceptin on April 25, 2024. A biosimilar means it is approved based on data demonstrating that it is highly similar to an FDA-approved biological product, known as a reference product (in this case, Herceptin) and that there are no clinically meaningful differences.

Hercessi side effects

Tell your healthcare provider immediately or seek emergency medical help if you have signs of an allergic or administration-related reaction such as dizziness, nausea, chills, fever, vomiting, diarrhea, hives, pain, headache, swelling under the skin, breathing problems, shortness of breath, or chest pain. Some side effects may occur during the injection, or in the days afterward. Tell your healthcare provider right away, even if these symptoms occur a few days later.

Hercessi can cause serious side effects (see warnings below). Call your doctor at once if you have:

Common side effects of Hercessi may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to Accord BioPharma Inc. at 1-866-941-7875 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.  

Warnings

Hercessi may exacerbate chemotherapy-induced neutropenia (low levels of neutrophils [a type of white blood cell] caused by cancer treatments).

Hercessi can cause heart failure, especially if you have heart disease or if you are also receiving certain other cancer medicines (such as daunorubicin, doxorubicin, epirubicin, or idarubicin). Your healthcare provider will assess your heart function before treatment and monitor you throughout.

Serious and fatal infusion reactions and pulmonary toxicity have been reported with trastuzumab infusions, including bronchospasm, anaphylaxis, angioedema, interstitial pneumonitis, or acute respiratory distress syndrome. Reactions usually occur during or immediately following the infusion. Your healthcare provider will monitor you during the infusion.

Hercessi can cause harm to an unborn baby and result in oligohydramnios (a reduction in the levels of amniotic fluid), and incomplete lung development, which can be fatal. Women of childbearing potential should use effective contraception.

Before taking

Tell your doctor if you have experienced an infusion reaction or hypersensitivity reaction to trastuzumab, or its biosimilars such as Herceptin, Herzuma, Kanjinti, Ontruzant, Hercessi, or Trazimera, or any of the inactive ingredients in the vial.

Hercessi is only administered to eligible patients identified as having HER2 protein overexpression and HER2 gene amplification using an FDA-approved test specific for breast or gastric cancers by laboratories with demonstrated proficiency.

Before taking Hercessi, tell your doctor if you:

Pregnancy

You may need to have a negative pregnancy test before starting this treatment. Do not use Hercessi if you are pregnant.

Hercessi may result in the death of an unborn baby or birth defects. Females with childbearing potential should use effective contraception while receiving Hercessi and for 7 months after the last dose. If you inadvertently become pregnant while receiving trastuzumab or within 7 months after your last dose, tell your doctor right away.

Breastfeeding

It is unknown if Hercessi passes into human milk. It may not be safe to breastfeed while using this medicine and for up to 7 months after your last dose. Ask your doctor about any risks.

How is Hercessi administered?

Hercessi is administered as an intravenous infusion by a healthcare provider.

You may need frequent medical tests to be sure this medicine is not causing harmful effects. Your cancer treatments may be delayed based on the results.

Your heart function may need to be checked before and during treatment with Hercessi. You may also need heart function testing every 6 months for 2 years after your last dose of this medicine.

Hercessi is usually given for 52 weeks, or until your body no longer responds to the medication.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your Hercessi.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while receiving Hercessi?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What other drugs will affect Hercessi?

Other drugs may affect Hercessi, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Patients who receive anthracycline during Hercessi treatment or within 7 months of stopping Hercessi are at increased risk of heart dysfunction.

Hercessi can have long-lasting effects on your heart, especially if you receive other cancer medicines, such as daunorubicin, doxorubicin, epirubicin, or idarubicin). For at least 7 months after your last dose of trastuzumab, tell any doctor who treats you that you have used Hercessi.

This is not a complete list of interactions. See the Hercessi Package Insert for more information.

Ingredients

Active: trastuzumab-strf 150mg in a single-dose vial for reconstitution.

Each vial must be reconstituted with 7.4 mL of Sterile Water for Injection (SWFI) (not supplied) to yield a single-dose solution containing 21 mg/mL trastuzumab-strf that delivers 7.15 mL (150 mg trastuzumab-strf). This is then added to an infusion bag containing 250 mL of 0.9% Sodium Chloride Injection.

Storage

Refrigerate at 2°C to 8°C (36°F to 46°F) in the original carton until the time of reconstitution. Do not freeze, do not shake.

Manufacturer

Accord BioPharma Inc.

Popular FAQ

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If you are receiving Perjeta for treatment of HER2+ early breast cancer, you may continue treatments with Herceptin every 3 weeks for one year (18 cycles total). For the treatment of HER2+ metastatic breast cancer, you will receive Perjeta and Herceptin until the medicine no longer controls your breast cancer or you have side effects that require you to stop treatment. You may receive other treatments with these medications. Continue reading

After Herceptin treatment, your doctor will monitor you regularly for cancer progression, advise you not to become pregnant for at least 7 months (if you are of childbearing potential), and test your heart every 6 months for at least 2 years, because there is a higher risk of developing long-term heart damage in people who take Herceptin. Continue reading

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Further information

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