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Phesgo (Subcutaneous)

Generic name: pertuzumab, trastuzumab, and hyaluronidase-zzxf (subcutaneous route) [ per-TOOZ-ue-mab, tras-TOOZ-oo-mab, hye-al-ure-ON-i-dase-- zzxf ]
Drug class: HER2 inhibitors

Medically reviewed by Last updated on Oct 28, 2021.

Subcutaneous route(Solution)

CardiomyopathyPertuzumab/trastuzumab/hyaluronidase-zzxf administration can result in subclinical and clinical cardiac failure manifesting as congesting heart failure, and decreased LVEF, with greatest risk when administered concurrently with anthracyclines. Evaluate cardiac function prior to and during treatment. Discontinue pertuzumab/trastuzumab/hyaluronidase-zzxf for cardiomyopathy.Embryo-fetal ToxicityExposure to pertuzumab/trastuzumab/hyaluronidase-zzxf can result in embryo-fetal death and birth defects. Advise patients of these risks and the need for effective contraception.Pulmonary ToxicityDiscontinue pertuzumab/trastuzumab/hyaluronidase-zzxf for anaphylaxis, angioedema, interstitial pneumonitis, or acute respiratory distress syndrome .

Commonly used brand name(s)

In the U.S.

  • Phesgo

Available Dosage Forms:

  • Solution

Therapeutic Class: Antineoplastic Agent

Pharmacologic Class: Monoclonal Antibody

Uses for Phesgo

Pertuzumab, trastuzumab, and hyaluronidase-zzxf combination injection is used first together with other cancer medicines to treat HER2-positive, locally advanced, inflammatory, or early stage breast cancer (either greater than 2 centimeters in diameter or node positive) as part of a complete treatment plan for early breast cancer. It is also used after an initial treatment plan to treat HER2-positive early breast cancer which has a high risk of occurring again.

Pertuzumab, trastuzumab, and hyaluronidase-zzxf combination injection is also used together with docetaxel to treat HER2-positive metastatic (cancer that has spread) breast cancer in patients who have not previously received cancer treatment.

Pertuzumab, trastuzumab, and hyaluronidase-zzxf combination prevents the growth of some tumors that produce extra amounts of a certain substance known as the HER2 protein. It should only be used in patients whose tumors have been shown to produce extra amounts of this protein (HER2 overexpression).

This medicine is to be given only by or under the direct supervision of your doctor.

Before using Phesgo

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies have not been performed on the relationship of age to the effects of pertuzumab, trastuzumab, and hyaluronidase-zzxf combination injection in the pediatric population. Safety and efficacy have not been established.


Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of pertuzumab, trastuzumab, and hyaluronidase-zzxf combination injection in the elderly. However, elderly patients are more likely to have age-related heart problems and other unwanted effects (eg, decreased appetite and weight, burning, numbness, tingling, or painful feeling of the skin, lack or loss of strength), which may require caution in patients receiving this medicine.


There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with medicines

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.

  • Daunorubicin
  • Daunorubicin Citrate Liposome
  • Daunorubicin Liposome
  • Doxorubicin
  • Doxorubicin Hydrochloride Liposome
  • Epirubicin
  • Idarubicin
  • Pirarubicin
  • Pixantrone
  • Tofacitinib
  • Valrubicin

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.

  • Warfarin

Interactions with food/tobacco/alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Heart disease or
  • Lung disease (eg, lung tumor) or
  • Neutropenia (low white blood cell count)—Use with caution. May make these conditions worse.

Proper use of Phesgo

Medicines used to treat cancer are very strong and can have many side effects. Before receiving this medicine, make sure you understand all the risks and benefits. It is important for you to work closely with your doctor during your treatment.

A doctor or other trained health professional will give you this medicine in a medical facility. It is given as a shot under the skin of your thigh for at least 8 minutes for the initial dose then for at least 5 minutes once every 3 weeks.

Your doctor may want you stay for at least 15 to 30 minutes after each injection to check for unwanted effects.

You may also receive other medicines (including allergy medicine, fever medicine, pain medicine) before starting treatment with this medicine to help prevent unwanted effects.

Missed dose

This medicine needs to be given on a fixed schedule. If you miss a dose, call your doctor, home health caregiver, or treatment clinic for instructions.

Precautions while using Phesgo

It is very important that your doctor check your progress closely and at regular visits to make sure that this medicine is working properly. Blood and urine tests may be needed to check for unwanted effects.

Receiving this medicine while you are pregnant can harm your unborn baby. If you are a woman who can bear children, your doctor may give you a pregnancy test before you start receiving this medicine to make sure you are not pregnant. You should use an effective form of birth control during treatment and for at least 7 months after the last dose. If you think you have become pregnant while receiving this medicine, tell your doctor right away.

This medicine may cause heart problems, including heart failure, thickening of the heart, heart rhythm problems, or high blood pressure. Your doctor may test your heart before and during treatment with this medicine. Contact your doctor right away if you experience any chest pain, fast, slow, or uneven heartbeat, increased coughing, trouble with breathing, a sudden difficulty with breathing at night, rapid weight gain, swelling in your ankles or legs, blurred vision, dizziness, or headache.

You may also have an increased risk of having heart problems if you receive an anthracycline medicine after treatment with this medicine. You should not receive an anthracycline medicine for up to 7 months after stopping treatment with this medicine.

Serious lung or breathing problems may occur after you receive this medicine and could be life-threatening. Check with your doctor right away if have changes in your breathing, chest tightness, or any type of breathing problem.

This medicine can temporarily lower the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.

This medicine may cause serious allergic reactions, including anaphylaxis, which can be life-threatening and requires immediate medical attention. Tell your doctor right away if you have a rash, itching, hoarseness, trouble breathing or swallowing, or any swelling of your hands, face, or mouth after receiving this medicine.

Phesgo side effects

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

  • Black, tarry stools
  • bladder pain
  • bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
  • bloody or cloudy urine
  • body aches or pain
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • chest pain or tightness
  • chills
  • cough
  • cracked lips
  • decreased urine
  • diarrhea
  • difficult, burning, or painful urination
  • difficult or labored breathing
  • difficulty swallowing
  • dry mouth
  • ear congestion
  • fever
  • frequent urge to urinate
  • general feeling of discomfort or illness
  • headache
  • increased thirst
  • irregular heartbeat
  • joint pain
  • lack or loss of strength
  • loss of appetite
  • loss of voice
  • lower back or side pain
  • mood changes
  • muscle pain or cramps
  • nausea
  • nosebleed
  • numbness or tingling in the hands, feet, or lips
  • pale skin
  • redness, swelling, pain of the skin
  • runny or stuffy nose
  • scaling of the skin on the hands and feet
  • seizures
  • shivering
  • sneezing
  • sore throat
  • sores, ulcers, or white spots on the lips, tongue, or inside the mouth
  • sweating
  • swelling of the hands, ankles, feet, or lower legs
  • trouble sleeping
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • vomiting

Less common

  • Dizziness
  • itching, skin rash


  • Chest discomfort
  • dilated neck veins
  • thickening of bronchial secretions
  • weight gain

Incidence not known

  • Agitation
  • bleeding gums
  • confusion
  • decreased awareness or responsiveness
  • depression
  • hostility
  • irritability
  • joint stiffness or swelling
  • loss of consciousness
  • lower back, side, or stomach pain
  • mood or mental changes
  • muscle twitching
  • pinpoint red spots on the skin
  • severe sleepiness
  • stomach cramps
  • tremor
  • unusual drowsiness, dullness, or feeling of sluggishness

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

  • Belching
  • bleeding after defecation
  • bone pain
  • change in or loss of taste
  • constipation
  • difficulty in moving
  • discoloration of the nails
  • dry eye or skin
  • feeling of warmth
  • heartburn
  • increased tearing of the eye
  • indigestion
  • pain and redness of the skin at the place of radiation treatment
  • redness of the face, neck, arms and occasionally, upper chest
  • stomach discomfort or upset
  • thinning or loss of hair
  • uncomfortable swelling around the anus

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.

More about Phesgo (hyaluronidase / pertuzumab / trastuzumab)

Patient resources

Professional resources

Related treatment guides

Further information

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