Zongertinib (Hernexeos®)

How to Take Zongertinib

This medication comes in tablet form that you take by mouth once daily. Take this medication with or without food and around the same time every day. Take the tablet whole, do not cut, break, crush or chew.

It is important to make sure you are taking the correct amount of medication every time. Before every dose, check that what you are taking matches what you have been prescribed.

If you miss a dose and it has been less than 12 hours since your regular dose time, take it as soon as you remember. If it has been more than 12 hours, skip the dose. Do not take 2 doses at once to make up for a missed dose.

The blood levels of this medication can be affected by certain medications, so they should be avoided. These include: verapamil, ketoconazole, rifampin, phenytoin, St. John’s wort, and modafinil. Be sure to tell your healthcare provider about all medications and supplements you take.

Storage and Handling

Store your medication in the original, labeled container at room temperature and in a dry location (unless otherwise directed by your healthcare provider or pharmacist). This medication should not be stored in a pillbox. Keep containers out of reach of children and pets.

If a caregiver prepares your dose for you, they should consider wearing gloves or pouring the pills directly from their container into the cap, a small cup, or directly into your hand. They should avoid touching the pills. They should always wash their hands before and after giving you the medication. Pregnant or nursing women should not prepare the dose for you. Ask your oncology team where to return any unused medication for disposal. Do not flush down the toilet or throw in the trash.

Where do I get this medication?

Certain cancer medications are only available through specialty pharmacies. If you need to get this medication through a specialty pharmacy, your provider will help you start this process. Where you can fill your prescriptions may also be influenced by your prescription drug coverage. Ask your health care provider or pharmacist for assistance in identifying where you can get this medication.

Insurance Information

Certain cancer medications are only available through specialty pharmacies. If you need to get this medication through a specialty pharmacy, your provider will help you start this process. Where you can fill your prescriptions may also be influenced by your prescription drug coverage. Ask your health care provider or pharmacist for assistance in identifying where you can get this medication.

Possible Side Effects of Zongertinib

There are a number of things you can do to manage the side effects of zongertinib. Talk to your care team about these recommendations. They can help you decide what will work best for you. These are some of the most common or important side effects:

Diarrhea

Your oncology care team can recommend medications to relieve diarrhea. Also, try eating low-fiber, bland foods, such as white rice and boiled or baked chicken. Avoid raw fruits, vegetables, whole grain breads, cereals and seeds. Soluble fiber is found in some foods and absorbs fluid, which can help relieve diarrhea. Foods high in soluble fiber include: applesauce, bananas (ripe), canned fruit, orange sections, boiled potatoes, white rice, products made with white flour, oatmeal, cream of rice, cream of wheat, and farina. Drink 8-10 glasses of non-alcoholic, un-caffeinated fluid a day to prevent dehydration.

Nail and Skin Changes

This medication has some unique nail and skin side effects that you may experience. Patients can develop a rash. While this rash may look like acne, it is not, and should not be treated with acne medications. The rash may appear red, swollen, crusty, dry and feel sore. You may also develop very dry skin, which may crack, be itchy or become flaky or scaly. The rash typically starts in the first week of treatment, but can occur at any time during treatment. Tips for managing your skin include:

• Use a thick, alcohol-free emollient lotion or cream on your skin at least twice a day, including right after bathing.
• Avoid sun exposure, as it can worsen the rash or cause a severe burn. Use a sunscreen with an SPF of 30 or higher and wear a hat and sunglasses to protect your head and face from the sun.
• Bathe/shower in cool or lukewarm (not hot) water and pat your skin dry.
• Use soaps, lotions and laundry detergents without alcohol, perfumes or dyes.
• Wear gloves to wash dishes or do housework or gardening.
• Drink plenty of water and try not to scratch or rub your skin.
• Notify your healthcare team if you develop a rash, as they can provide suggestions to manage the rash and/or prescribe a topical medication to apply to the rash or an oral medication.
• If you develop peeling or blistering of the skin, notify your healthcare team right away.

While receiving this medication you may develop an inflammation of the skin around the nail bed/cuticle areas of toes or fingers, which is called paronychia. It can appear red, swollen or pus filled. Nails may develop "ridges" in them or fall off. You may also develop cuts or cracks that look like small paper cuts in the skin on your toes, fingers or knuckles. These side effects may appear several months after starting treatment, but can last for many months after treatment stops.

• Follow the same recommendations for your skin (above).
• Don't bite your nails or cuticles or cut the cuticles.
• Keep your fingernails and toenails clean and dry.
• You may use nail polish, but do not wear fake nails (gels, acrylics, overlay).
• Notify your healthcare provider if any nails fall off or you develop any of these side effects or other skin abnormalities.

Liver Toxicity

This medication can cause liver toxicity, which your oncology care team may monitor for using blood tests called liver function tests. Notify your healthcare provider if you notice yellowing of the skin or eyes, your urine appears dark or brown, or you have pain in your abdomen, as these can be signs of liver toxicity.

Fatigue

Fatigue is very common during cancer treatment and is an overwhelming feeling of exhaustion that is not usually relieved by rest. While on cancer treatment, and for a period after, you may need to adjust your schedule to manage fatigue. Plan times to rest during the day and conserve energy for more important activities. Exercise can help combat fatigue; a simple daily walk with a friend can help. Talk to your healthcare team for helpful tips on dealing with this side effect.

Nausea and/or Vomiting

Talk to your oncology care team so they can prescribe medications to help you manage nausea and vomiting. In addition, dietary changes may help. Avoid things that may worsen the symptoms, such as heavy or greasy/fatty, spicy or acidic foods (lemons, tomatoes, oranges). Try saltines, or ginger ale to lessen symptoms.

Call your oncology care team if you are unable to keep fluids down for more than 12 hours or if you feel lightheaded or dizzy at any time.

Muscle or Joint Pain

Your healthcare provider can recommend medications and other strategies to help relieve pain.

Low White Blood Cell Count (Leukopenia, Lymphopenia)

White blood cells (WBC) are important for fighting infection. While receiving treatment, your WBC count can drop, putting you at a higher risk of getting an infection. You should let your doctor or nurse know right away if you have a fever (temperature greater than 100.4°F or 38°C), sore throat or cold, shortness of breath, cough, burning with urination, or a sore that doesn't heal.

Tips for preventing infection:

• Washing hands, both yours and your visitors, is the best way to prevent the spread of infection.
• Avoid large crowds and people who are sick (i.e.: those who have a cold, fever, or cough or live with someone with these symptoms).
• When working in your yard, wear protective clothing including long pants and gloves.
• Do not handle pet waste.
• Keep all cuts or scratches clean.
• Shower or bathe daily and perform frequent mouth care.
• Do not cut cuticles or ingrown nails. You may wear nail polish, but not fake nails.
• Ask your oncology care team before scheduling dental appointments or procedures.
• Ask your oncology care team before you, or someone you live with has any vaccinations.

Upper Respiratory Infection (URI)

An upper respiratory infection causes swelling or irritation in your upper airways. It can cause a runny nose, cough, and sore throat. Call your provider if you have any of these symptoms and for ways to manage a URI.

Low Red Blood Cell Count (Anemia)

Your red blood cells are responsible for carrying oxygen to the tissues in your body. When the red cell count is low, you may feel tired or weak. You should let your oncology care team know if you experience any shortness of breath, difficulty breathing or pain in your chest. If the count gets too low, you may receive a blood transfusion.

Pancreas Problems

Bloating, indigestion, fatty stools, loss of appetite, sweating, abdominal pain, and weight loss can all be symptoms of pancreatitis (inflammation of the pancreas). Notify your care provider if you have any of these symptoms.

Electrolyte Abnormalities

This medication can affect the normal levels of electrolytes (calcium, sodium, potassium, magnesium, etc.) in your body. Your levels will be monitored using blood tests. If your levels become too low, your care team may prescribe specific electrolytes to be given by IV or taken by mouth. Do not take any supplements without first consulting with your care team.

Increased Blood Cholesterol 

This medication can cause an increase in your cholesterol levels. Your healthcare team will monitor your cholesterol levels throughout your treatment.

Important but Less Common Side Effects

• Heart Problems: This medication can affect how well your heart pumps blood, called left ventricular dysfunction. Your heart function will be checked before and during treatment with this medication. You should contact your provider right away if you have new or worsening shortness of breath, feeling more tired than normal, your feet or ankles are swollen, you lose consciousness, your heart feels like it is beating fast or skipping a beat, sudden weight gain, or feeling dizzy or lightheaded.
• Lung Problems: Patients can develop an inflammation of the lungs (called pneumonitis) or interstitial lung disease that causes lung scarring while taking this medication. Notify your oncology care team right away if you develop any new or worsening symptoms, including shortness of breath, trouble breathing, cough or fever.

Reproductive Concerns

Exposure of an unborn child to this medication could cause birth defects, so you should not become pregnant or father a child while on this medication. Effective birth control is necessary during treatment and for at least 2 weeks after your last dose. Even if your menstrual cycle stops or you believe you are not producing sperm, you could still be fertile and conceive. You should not breastfeed during treatment and for 2 weeks after your last dose.