What is ENHERTU?
ENHERTU is a prescription medicine used to treat adults who have:
- human epidermal growth factor receptor 2 (HER2)-positive breast cancer that cannot be removed by surgery or has spread to other parts of the body (metastatic) in combination with pertuzumab as your first treatment. Your healthcare provider will perform a test to make sure ENHERTU in combination with pertuzumab is right for you.
- HER2-positive breast cancer that cannot be removed by surgery or that has spread to other parts of the body (metastatic), and who have received a prior anti-HER2 breast cancer treatment for metastatic disease or have breast cancer that has come back during or within 6 months of completing treatment for their early-stage breast cancer.
It is not known if ENHERTU is safe and effective in children.
What is the most important information I should know about ENHERTU?
ENHERTU can cause serious side effects, including:
- Lung problems that may be severe, life-threatening or that may lead to death.
If you develop lung problems your healthcare provider may
treat you with corticosteroid medicines. Tell your healthcare provider right
away if you get any of the following signs and symptoms:
- cough
- trouble breathing or shortness of breath
- fever
- other new or worsening breathing symptoms (such as chest tightness,
wheezing)
- Low white blood cell count (neutropenia). Low white blood cell counts are common with ENHERTU and can sometimes be severe. Your healthcare provider will check your white blood cell counts before starting ENHERTU and before starting each dose. Tell your healthcare provider right away if you develop any signs or symptoms of an infection or have fever or chills during treatment with ENHERTU.
- Heart problems that may affect your heart's ability to
pump blood. Your healthcare provider will check your heart function before starting treatment with ENHERTU. Tell your healthcare provider right away if you get any of the following signs and symptoms:
- new or worsening shortness of breath
- coughing
- feeling tired
- swelling of your ankles or legs
- irregular heartbeat
- sudden weight gain
- dizziness or feeling light-headed
- loss of consciousness
Your healthcare provider will check you for these side effects during your treatment with ENHERTU. Your healthcare provider may reduce your dose, delay treatment or completely stop treatment with ENHERTU if you have severe side effects.
- Harm to your unborn baby. Tell your healthcare provider right away if you become pregnant or think you might be pregnant during treatment with ENHERTU.
- If you are able to become pregnant, your healthcare provider should do a pregnancy test before you start treatment with ENHERTU.
- Females who are able to become pregnant should use effective birth control (contraception) during treatment with ENHERTU and for 7 months after the last dose.
- Males who have female partners who are able to become pregnant should use effective birth control (contraception) during treatment with ENHERTU and for 4 months after the last dose.
Before you receive ENHERTU, tell your healthcare provider about all of your medical conditions, including if you:
- have lung or breathing problems
- have signs or symptoms of an infection
- have or have had any heart problems
- are breastfeeding or plan to breastfeed. It is not known if ENHERTU passes into your breast milk. Do not breastfeed during treatment with ENHERTU and for 7 months after the last dose.
Tell your healthcare provider about
all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
How will I receive ENHERTU?
- You will receive ENHERTU into your vein through an intravenous (IV) line by your healthcare provider.
- ENHERTU is given 1 time every three weeks (21-day treatment cycle).
- Your healthcare provider will decide how many treatments you need.
- Your healthcare provider will give you medicines before your infusion to help prevent nausea and vomiting.
- Your healthcare provider may slow down or temporarily stop your infusion of ENHERTU if you have an infusion-related reaction, or permanently stop ENHERTU if you have severe infusion reactions.
- If you miss a planned dose of ENHERTU, call your healthcare provider right away to schedule an appointment. Do not wait until the next planned treatment cycle.
What are the possible side effects of
ENHERTU?
ENHERTU can cause serious side effects. See "What is
the most important information I should know about ENHERTU?"
The most common side effects of ENHERTU, when used alone at the 5.4 mg/kg dose in people with metastatic breast cancer, HER2-mutant non-small cell lung cancer, and other HER2-positive solid tumors include:
- low white blood cell counts
- nausea
- low red blood cell counts
- feeling tired
- low platelet counts
- increased liver function tests
- vomiting
- hair loss
- constipation
- low levels of blood potassium
- decreased appetite
- diarrhea
- muscle or bone pain
The most common side effects of ENHERTU, when used in combination with pertuzumab at the 5.4 mg/kg dose in people with HER2-positive metastatic breast cancer include:
- low white blood cell counts
- low red blood cell counts
- nausea
- increased liver function tests
- diarrhea
- low platelet counts
- low levels of blood potassium
- feeling tired
- hair loss
- vomiting
- upper respiratory tract infection
- constipation
- decreased appetite
- weight loss
- COVID-19
- muscle or bone pain
- stomach pain
ENHERTU may cause fertility problems in males, which may affect the ability to father children. Talk to your healthcare provider if you have concerns about fertility.
These are not all of the possible side effects of ENHERTU.
Call your doctor for medical advice about side effects. You may report side
effects to FDA at 1-800-FDA-1088.
Please see full Prescribing Information,
including Boxed WARNINGS, and Medication Guide.
