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What is PHESGO?

A different approach to HER2+ breast cancer treatment

PHESGO offers a different way to get your HER2-positive breast cancer treatment. It brings together PERJETA® (pertuzumab) and Herceptin® (trastuzumab) in a single injection just under the skin.

Injection needle

PERJETA and Herceptin are 2 HER2-targeted therapies used together to treat HER2+ breast cancer, alongside chemotherapy.

Targeted cancer treatments are designed to target specific characteristics of cancer cells, but may also affect healthy cells. They are different from traditional chemotherapy. Chemotherapy kills cells that grow and divide rapidly, regardless of whether they are healthy cells or cancer cells.

HER2-targeted treatments are designed to bind to HER2 receptors to fight cancer cells that have too many HER2 receptors. Keep in mind that healthy cells also have HER2 receptors—just not as many—so these types of treatments can affect healthy cells, too.

PERJETA and Herceptin are given by infusion, either through an IV or through a port.

PHESGO also contains a protein called hyaluronidase that helps your body absorb these 2 medicines and allows them to be given as a single injection in about 5 minutes.* How is that possible? >

PHESGO is given as part of a complete treatment regimen for HER2+ breast cancer that includes chemotherapy.

*Your first dose is given in ~8 minutes. This does not account for observation time and other aspects of treatment. Actual clinic time may vary.

Designed to make part of your treatment faster

PHESGO contains the same medicines that are inside PERJETA and Herceptin. The main difference between them is how it’s given.

PERJETA and Herceptin are given as 2 separate infusions, either through an IV or through a port, whereas PHESGO is given as one injection just under the skin in the thigh.

By taking PHESGO, you’re taking the same medicines, just in less time.

~5 minutes for PHESGO injection vs 1-2.5 hours for PERJETA + Herceptin infusion (maintenance dose time)

This does not account for observation time and other aspects of treatment. Actual clinic time may vary.

If you’re already receiving PERJETA + Herceptin, your doctor may be able to switch you to PHESGO if they think it’s right for you.

Get more information about the injection experience and what you may expect.

Getting the injection
PRC-icon
Have questions?

Call the Patient Resource Center for answers to your questions about PHESGO or other resources from Genentech.

1 (877) GENENTECH (1-877-436-3683)

Monday-Friday, 6am-5pm PST

This is not meant to replace the advice of your healthcare team.

Important Safety Information & Uses

What does PHESGO treat?

PHESGO® (pertuzumab, trastuzumab, and hyaluronidase-zzxf) is a prescription medicine approved for use in combination with chemotherapy for:

  • use prior to surgery (neoadjuvant treatment) in adults with HER2-positive, locally advanced, inflammatory, or early stage breast cancer (tumor is greater than 2 cm in diameter or node-positive). PHESGO should be used as part of a complete treatment regimen for early breast cancer. 
  • use after surgery (adjuvant treatment) in adults with HER2-positive early breast cancer that has a high likelihood of coming back.

PHESGO is a prescription medicine approved for use in combination with docetaxel in adults who have HER2-positive breast cancer that has spread to different parts of the body (metastatic) and who have not received anti-HER2 therapy or chemotherapy for metastatic breast cancer.

What should I know about side effects with PHESGO?

  • Not all people have serious side effects; however, side effects with PHESGO therapy are common. It is important to know what side effects may happen and what symptoms you should watch for
  • Your doctor may stop treatment if serious side effects happen. Be sure to contact your healthcare team right away if you have questions or are worried about any side effects

What are the most serious side effects of PHESGO?

PHESGO may cause heart problems, including those without symptoms (such as reduced heart function) and those with symptoms (such as congestive heart failure).

  • The risk for and seriousness of these heart problems are highest in people who received both PHESGO and a certain type of chemotherapy (anthracycline)
  • Your doctor will check for signs of heart problems before, during, and after treatment with PHESGO. Based on test results, your doctor may hold or discontinue treatment with PHESGO
  • Contact a healthcare professional immediately for any of the following: 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

Receiving PHESGO during pregnancy can result in the death of an unborn baby and birth defects.

  • Birth control should be used while receiving PHESGO and for 7 months after your last dose of PHESGO. If you are a mother who is breastfeeding, you should talk with your doctor about either stopping breastfeeding or stopping PHESGO
  • If you think you may be pregnant, you should contact your healthcare provider immediately
  • If you are exposed to PHESGO during pregnancy, or become pregnant while receiving PHESGO or within 7 months following the last dose of PHESGO, you are encouraged to report PHESGO exposure to Genentech at 1-888-835-2555

PHESGO may cause serious lung problems.

  • Your doctor may check for signs of lung problems including:
    • Severe shortness of breath
    • Fluid in or around the lungs
    • Weakening of the valve between the heart and the lungs
    • Not enough oxygen in the body
    • Swelling of the lungs
    • Scarring of the lungs

Who should not receive PHESGO?

  • PHESGO should not be used in patients who are allergic to pertuzumab, trastuzumab, hyaluronidase, or to any of the ingredients in PHESGO

What are other possible serious side effects?

  • PHESGO may worsen low white blood cell counts caused by chemotherapy: Low white blood cell counts can be life threatening and were seen more often in patients receiving Herceptin® (trastuzumab) plus chemotherapy than in patients receiving chemotherapy alone. Your doctor may check for signs of low white blood cell counts when he or she examines you
  • PHESGO may cause administration-related reactions: PHESGO is given as an injection. The active ingredients in PHESGO have been associated with severe administration reactions, including hypersensitivity or anaphylaxis, which can be fatal. Talk to your doctor if you feel any symptoms. The most common symptoms include dizziness, nausea, chills, fever, vomiting, diarrhea, hives, swelling of the skin, breathing problems, or chest pain

What are the most common side effects?

The most common side effects of PHESGO when given with chemotherapy as part of an early breast cancer regimen are:

  • Hair Loss
  • Nausea
  • Diarrhea
  • Low levels of red blood cells
  • Weakness

The most common side effects of PHESGO when given with docetaxel for treatment of breast cancer that has spread to other parts of the body (metastatic) are:

  • Diarrhea
  • Hair loss
  • Low levels of white blood cells with or without fever
  • Nausea
  • Feeling tired
  • Rash
  • Damage to the nerves (numbness, tingling, pain in hands/feet)

You are encouraged to report side effects to Genentech and the FDA. You may report side effects to the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Genentech at 1-888-835-2555.

Talk to a healthcare professional for more information about the benefits and risks of PHESGO. 

Please see full Prescribing Information for additional Important Safety Information, including most serious side effects.

If you cannot afford your medication, visit genentech-access.com/patient for financial assistance information.