Last Modified: November 19, 2015
Classification: Kinase Inhibitor
BRAF is a protein kinase that plays a role in regulating genes that are responsible for cell replication and survival. It is estimated that 50% of melanomas contain an abnormal form of BRAF (also called a mutation). This mutated form of BRAF promotes overgrowth of these cancer cells. Vemurafenib works by blocking the actions of the abnormal BRAF, inhibiting cell replication and potentially causing cell death.
How to Take Vemurafenib
Vemurafenib is given in a tablet form and taken twice a day. You will need to take several tablets to get the full dose. Vemurafenib tablets should be taken whole, with a glass of water, and should not be crushed, broken or chewed. They can be taken with or without food. If you miss a dose, you can take the dose up to 4 hours before the next scheduled dose. Do not take two doses at once to make up for a missed dose.
The blood levels of this medication can be affected by certain foods and medications, so they should be avoided. These include: grapefruit, grapefruit juice, verapamil, ketoconazole, rifampin, phenytoin, St. John’s wort, modafanil, and many others. Be sure to tell your healthcare provider about all medications and supplements you take.
Because this medication only works in melanoma that has a specific BRAF mutation, called V600E, this abnormality must be tested for prior to starting the medication to identify patients appropriate for therapy. In order to test for mutated BRAF, a sample of the tumor is sent to a special laboratory that performs this test.
Storage and Handling
Store this medication at room temperature in the original container. If you prefer to use a pillbox, discuss this with your oncology pharmacist. 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?
Vemurafenib is available through select specialty pharmacies. Your oncology team will work with your prescription drug plan to identify an in-network specialty pharmacy for distribution of this medication and shipment directly to your home.
This medication may be covered under your prescription drug plan. Patient assistance may be available to qualifying individuals without prescription drug coverage. Co-pay cards, which reduce the patient co-pay responsibility for eligible commercially (non-government sponsored) insured patients, may also be available. Your care team can help you find these resources, if they are available.
Possible Side Effects of Vemurafenib
There are a number of things you can do to manage the side effects of vemurafenib. Talk to your doctor or nurse about these recommendations. They can help you decide what will work best for you. These are some of the most common side effects:
Your skin will be more sensitive to the sun, which can result in severe sunburn or rash. Sun sensitivity can last even after vemurafenib is stopped. Avoid the sun between 10-2pm, when it is strongest. Wear sunscreen (at least SPF 15) everyday; wear sunglasses, a hat and long sleeves/pants to protect your skin, a lip balm with SPF>30, and seek out shade whenever possible.
Notify your care team if you develop red, painful or itchy skin, “sunburn”, skin irritation, bumps or thick, dry skin.
Rash and Allergic Reactions
Some patients can develop a reaction to vemurafenib, which can include rash (on any part of your skin including inside your mouth or the soles of your feet), skin redness, blistering, peeling or a serious allergic reaction causing difficulty breathing, rapid heartbeat, swelling or fever. If you have any side effects while taking this medication, inform you oncology team right away or go to the emergency room.
Nausea and/or Vomiting
Talk to your doctor or nurse 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 antacids, (e.g. milk of magnesia, calcium tablets such as Tums), saltines, or ginger ale to lessen symptoms.
Call your doctor or nurse 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.
Loss or Thinning of Scalp and Body Hair (Alopecia)
Your hair may become thin, brittle, or may fall out. This typically begins two to three weeks after treatment starts. This hair loss can be all body hair, including pubic, underarm, legs/arms, eyelashes, and nose hairs. The use of scarves, wigs, hats and hairpieces may help. Hair generally starts to regrow soon after treatment is completed. Remember your hair helps keep you warm in cold weather, so a hat is particularly important in cold weather or to protect you from the sun.
Decrease in Appetite
Nutrition is an important part of your care. Cancer treatment can affect your appetite and, in some cases, the side effects of treatment can make eating difficult. Ask your nurse about nutritional counseling services at your treatment center to help with food choices.
- Try to eat five or six small meals or snacks throughout the day, instead of 3 larger meals.
- If you are not eating enough, nutritional supplements may help.
- You may experience a metallic taste or find that food has no taste at all. You may dislike foods or beverages that you liked before receiving cancer treatment. These symptoms can last for several months or longer after treatment ends.
- Avoid any food that you think smells or tastes bad. If red meat is a problem, eat chicken, turkey, eggs, dairy products and fish without a strong smell. Sometimes cold food has less of an odor.
- Add extra flavor to meat or fish by marinating it in sweet juices, sweet and sour sauce or dressings. Use seasonings like basil, oregano or rosemary to add flavor. Bacon, ham and onion can add flavor to vegetables.
New Skin Cancer
In clinical trials, some patients developed a new skin cancer (Basal cell or squamous cell cancer). You should have skin examinations prior to starting treatment, and then every 2 months while on therapy, and for 6 months after the medication has been stopped. Check your own skin regularly and report any new growths, sores or bumps that bleed or do not heal, or notice any changes in moles to your healthcare provider.
This medication can affect the electrical activity in your heart, causing an abnormal heart rhythm called QT prolongation. Notify your healthcare provider right away if you feel abnormal heartbeats or if you feel dizzy, lightheaded, or faint.
In clinical trials, several patients developed a condition called uveitis, which is a swelling or irritation of the middle layer of the eye. Symptoms of this condition include blurry vision, "floaters" (dark spots in the field of vision), eye redness or pain, and sensitivity to light. If you develop any of these symptoms, notify your healthcare provider right away.
This medication can cause liver toxicity, which your doctor 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 pain in your abdomen, as these can be signs of liver toxicity.
Radiation recall is when the administration of a medication causes a skin reaction, that looks like a sunburn (redness, swelling, soreness, peeling skin), in areas where radiation was previously given. Radiation sensitization can occur when radiation is given at the same time or after treatment with this medication and can cause the same type of reaction. Notify your oncology team if you notice this side effect or if you plan to have radiation therapy.
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 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 consult with your healthcare team before breastfeeding while receiving this medication.