What is the most important information I should know about ENHERTU?
ENHERTU can cause serious side effects
Some serious or life-threatening side effects may affect your lungs, heart, or white blood cell count, affecting your ability to fight infection.
Pay special attention to new or worsening symptoms as they may be related to:
Lung problems, like interstitial lung disease/pneumonitis, that may be severe, life-threatening, or that may lead to death
Call or see your healthcare provider right away if you develop any of the following signs and symptoms or if these symptoms get worse:
- Cough
- Trouble breathing or shortness of breath
- Fever
- Other new or worsening breathing symptoms (such as chest tightness, wheezing)
If lung problems develop, your healthcare provider may treat you with corticosteroid medicines.
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
These are not all of the possible side effects of ENHERTU. Call your doctor for medical advice about side effects.
During treatment with ENHERTU, side effects may occur and you should notify your healthcare provider as early as possible
The most common side effects of ENHERTU when used at the 5.4 mg/kg dose 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
- 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 majority of side effects in people receiving ENHERTU were mild or moderate*; however, some people may have serious side effects that could lead to death. It is important to call your doctor for medical advice about side effects.
These are not all of the possible side effects of ENHERTU. Call your doctor for medical advice about side effects.
*Mild side effects are side effects you may have, but they may not show outward signs and medical intervention may not be needed. Moderate side effects may require some medical intervention or may affect you as you do day-to-day activities.
Steps you can take to help proactively manage some of ENHERTU side effects
These tips are not a substitute for your healthcare team's advice. Always talk to your doctor about any side effects you're experiencing for personalized guidance and appropriate treatments.
- Drink plenty of fluids each day to help manage tiredness and fatigue
- To proactively manage diarrhea, it's crucial to drink clear liquids to replace lost fluids. Check with your doctor on how much and what types of fluids are best for you
- When your energy levels are higher, it is recommended to participate in exercise, such as a combination of aerobic and resistance training. Always check with your doctor beforehand
- Plan regular rest periods and avoid overexerting yourself to combat tiredness and fatigue. Let others help with daily tasks when possible
- Try relaxation techniques like meditation or tai chi to help reduce stress and promote relaxation, which can alleviate fatigue
- Eat 5 or 6 small meals and snacks each day instead of 3 large meals to help with nausea, vomiting, and diarrhea. Choose bland, easy-to-digest foods and avoid strong smells
- Talk to your doctor about nausea medication. You should receive medicines before your infusion to help prevent nausea and vomiting
- To proactively manage diarrhea, focus on eating low-fiber foods to ease symptoms
- Be gentle when washing your hair to manage hair thinning or loss. Use a mild shampoo and avoid harsh hair treatments, such as dyes, perms, or relaxers
- Consider cutting your hair short to feel more in control of hair loss. Talk to your doctor about using cold caps or scalp cooling systems, which may reduce hair loss
- Wear a hat or head covering and apply sunscreen to protect your scalp if experiencing hair thinning or loss. Avoid exposing your scalp to extreme temperatures
- Sleep on a satin pillowcase for added comfort and to reduce friction
- If you feel nauseous or like vomiting, try taking slow, deep breaths and getting fresh air to help alleviate symptoms
- Practicing breathing exercises or engaging in other anxiety-reducing activities can help prevent or lessen nausea and vomiting
What may my healthcare provider do if I have side effects?
Your healthcare provider may modify your dose to help you manage side effects. It is important to call your healthcare provider right away for medical advice. To help manage side effects, your healthcare provider may:
Treat
side effects
Delay
your dose
Reduce
your dose
Stop
ENHERTU
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:
- 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
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.
Before you receive ENHERTU, tell your healthcare provider about all of your medical conditions, including if you:
- Have lung or breathing problems.
- Have kidney problems. Your healthcare provider may follow you more closely. In clinical trials, more serious lung problems were seen in patients with certain kidney problems.
- Have liver problems. Your healthcare provider may follow you more closely.
- 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.
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.
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