Classification: Monoclonal Antibody
About: Amivantamab-vmjw (Rybrevant®)
Monoclonal antibodies are created in a lab to attach to the targets found on specific types of cancer cells. The antibody “calls” the immune system to attack the cell it is attached to, resulting in the immune system killing the cell. These antibodies can work in different ways, including stimulating the immune system to kill the cell, blocking cell growth or other functions necessary for cell growth.
Amivantamab is a monoclonal antibody that works on certain cancers that have mutations (genetic changes) in proteins called epidermal growth factor receptor (EGFR) and mesenchymal-epithelial transition (MET). The EGFR is a protein that is abnormally over-expressed in many cancers. Amivantamab works specifically on tumors with EGFR exon 20 insertion mutations. These mutations are found with an FDA-approved blood test that you will have before starting treatment with amivantamab.
How to Take Amivantamab
Amivantamab is given through intravenous (IV, into a vein) infusion. The dose is based on your size and how often you receive the medication will be determined by your healthcare provider. Before your first dose you will be given pre-medications such as diphenhydramine (Benadryl), acetaminophen (Tylenol), and a steroid to prevent an infusion reaction. You may or may not receive these same pre-medications before your next doses.
Possible Side Effects
There are a number of things you can do to manage the side effects of Amivantamab. 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:
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 (belly), as these can be signs of liver toxicity.
Some patients may develop a rash, scaly skin, or red itchy bumps. For some patients, this rash may look like acne, it is not, and should not be treated with acne medications. Use an alcohol free moisturizer on your skin and lips; avoid moisturizers with perfumes or scents. Your oncology care team can recommend a topical medication if itching is bothersome. If your skin does crack or bleed, be sure to keep the area clean to avoid infection. Be sure to notify your oncology care team of any rash that develops, as this can be a reaction. They can give you more tips on caring for your skin. 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.
- Limit sun exposure during and for 2 months after treatment, 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.
Infusion-Related Side Effects
The infusion can cause a reaction that may lead to chills, fever, low blood pressure, nausea, and vomiting. You will receive acetaminophen (Tylenol) and diphenhydramine (Benadryl), as well as a steroid, prior to the infusion to help prevent these reactions. Reactions are most common during and after the first infusion but can happen at any point during your treatment course. Your oncology care team will tell you what to do if this happens.
Nail and Skin Changes
While receiving amivantamab, you may develop an inflammation (swelling and irritation) 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 rash and skin care (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.
- Notify your doctor or nurse if any nails fall off or you develop any of these side effects or other skin abnormalities.
Muscle or Joint Pain/Aches
Your healthcare provider can recommend medications and other strategies to help relieve pain.
This medication can cause kidney problems, including an increased creatinine level, which your oncology care team may monitor for using blood tests. Notify your healthcare provider if you notice decreased urine output, blood in the urine, swelling in the ankles, or loss of appetite.
Cough and/or Shortness of Breath
Amivantamab can cause a new or worsening cough. Call your provider if this happens. If you have shortness of breath, with or without activity, call your provider right away. If you have a hard time breathing, call 911 right away.
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.
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.
Low White Blood Cell Count (Leukopenia or Neutropenia)
White blood cells (WBC) are important for fighting infection. While receiving treatment, your WBC count can drop, particularly your lymphocyte count, 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 to 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 bath 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.
This medication can affect the normal levels of electrolytes (potassium, magnesium, sodium, 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.
Peripheral edema is swelling of the extremities caused by retention of fluid. It can cause swelling of the hands, arms, legs, ankles, and feet. The swelling can become uncomfortable. Notify your oncology care team if you are experiencing any new or worsening swelling.
Mouth Sores (Mucositis)
Certain cancer treatments can cause sores or soreness in your mouth and/or throat. Notify your doctor or nurse if your mouth, tongue, inside of your cheek or throat becomes white, ulcerated, or painful. Performing regular mouth care can help prevent or manage mouth sores. If mouth sores become painful, your doctor or nurse can recommend a pain reliever.
- Brush with a soft-bristle toothbrush or cotton swab twice a day.
- Avoid mouthwashes that contain alcohol. A baking soda and/or salt warm water mouth rinse (2 level teaspoons of baking soda or 1 level teaspoon salt in an eight ounce glass of warm water) is recommended 4 times daily.
- If your mouth becomes dry, eat moist foods, drink plenty of fluids (6-8 glasses), and suck on sugarless hard candy.
- Avoid smoking and chewing tobacco, drinking alcoholic beverages, and citrus juices.
There are several things you can do to prevent or relieve constipation. Include fiber in your diet (fruits and vegetables), drink 8-10 glasses of non-alcoholic fluids a day, and keep active. A stool softener once or twice a day may prevent constipation. If you do not have a bowel movement for 2-3 days, you should contact your healthcare team for suggestions to relieve the constipation.
Less Common, but important side effects can include:
- Pneumonitis: Patients can develop an inflammation of the lungs (called pneumonitis) 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
- Eye problems: This medication can cause problems with your eyes, including inflammation, redness, dry eye, blurred or troubled vision, and itching. Call your provider right away if you notice any changes in your vision or eyes.
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 3 months after treatment. 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 while receiving this medication and for 3 months after your last dose.