What is ENHERTU?
ENHERTU is a prescription medicine used to treat adults who have:
- HER2-low breast cancer that cannot be removed by surgery or that has spread to other parts of your body (metastatic), and who have received a prior chemotherapy:
- for metastatic disease, or
- your disease has returned during or within 6 months of completing adjuvant chemotherapy (after surgery). Your healthcare provider will perform a test to make sure ENHERTU is right for you.
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 that 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 at
the 5.4 mg/kg dose include:
- Nausea
- Low white blood cell counts
- Low red blood cell counts
- Feeling tired
- Low platelet counts
- Increased liver function tests
- Vomiting
- Hair loss
- Constipation
- Decreased appetite
- Low levels of blood potassium
- Diarrhea
- Muscle or bone pain
- Stomach-area 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 Daiichi Sankyo at 1-877-437-7763 or to FDA at 1-800-FDA-1088.
Please see full Prescribing Information,
including Boxed WARNINGS, and Medication Guide.
