Mektovi (binimetinib) is a MEK inhibitor that's used to treat adults with melanoma (a type of skin cancer) or non-small cell lung cancer (NSCLC). These cancers must have a certain mutation known as a BRAF mutation. Treatment with Mektovi (binimetinib) is convenient because it’s a tablet that's taken by mouth, but it must be taken with another medication called Braftovi (encorafenib) to treat the cancer better. Mektovi (binimetinib) can cause side effects such as nausea, diarrhea, and serious eye problems.
Melanoma with certain BRAF mutations that has spread (metastatic) or can’t be removed by surgery; used with Braftovi (encorafenib)
Metastatic non-small cell lung cancer (NSCLC) with certain BRAF mutations; used with Braftovi (encorafenib)
Mektovi (binimetinib) is a kinase inhibitor known as a MEK inhibitor. The MEK protein is part of a whole chain of proteins that help cells grow. By blocking MEK, this medication helps stop tumor growth.
Mektovi (binimetinib) is taken together with an anticancer medication called Braftovi (encorafenib) that specifically targets another protein in this chain (the BRAF protein). When the BRAF protein is mutated, the cancer grows uncontrollably and can spread more quickly.
By blocking two different proteins in this pathway, Mektovi (binimetinib) and Braftovi (encorafenib) work together to stop the cancer from growing and spreading.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Taken by mouth, so it’s a good option for people who don’t like needles
Can take with or without food
Works in a more specific targeted way than traditional chemotherapy
Recommended treatment option for people with BRAF-mutated melanoma
Must take with a second medication, so might be less convenient
Often causes tiredness, nausea, and diarrhea (usually mild)
Might cause vision changes, which can be signs of serious eye problems
Requires regular blood tests to check for side effects
Take Mektovi (binimetinib) twice a day, around 12 hours apart. You’ll need to take it with Braftovi (encorafenib), which is taken once a day. You can take both medications with or without food.
You might have mild nausea while you're taking Mektovi (binimetinib). Your provider might suggest you take a medication to prevent nausea before each dose. Tell your provider if you have nausea while you're taking Mektovi (binimetinib).
If you miss a dose of Mektovi (binimetinib) and you have more than 6 hours until your next usual dose time, you should take the dose. But if it’s less than 6 hours until the next time you typically take your dose, skip the dose you missed.
Make sure you drink plenty of fluids if you have diarrhea while you’re taking Mektovi (binimetinib). Avoid sugary sports drinks, though, because they can make diarrhea worse. Your provider might recommend over-the-counter diarrhea medications, like loperamide (Imodium A-D), to help.
Ask your provider about the best way to safely handle and throw away Mektovi (binimetinib). Anticancer medications can be harmful to people who handle or come in contact with them. You should store the medication up and away, so children and pets won’t be able to reach it.
It isn't recommended to breastfeed while you're taking Mektovi (binimetinib). We don’t know whether the medication is found in breast milk and whether it affects breastfed babies. But because of the possible risks to a baby, it’s best to avoid nursing if you’re taking Mektovi (binimetinib) and for 3 days after the last dose.
Mektovi (binimetinib) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
There's a risk that new cancers can appear when you take Mektovi (binimetinib) with Braftovi (encorafenib). In clinical studies, a few people who took these two medications together reported having certain types of skin cancer. Your care team will check for new cancers often. This includes examining you before treatment, while you're taking the medications, and after you've stopped treatment. Tell your provider if you have an unexplained fever, feel very tired, have swollen lymph nodes in your neck or armpits, or spots or moles on your skin that seem unusual.
Though uncommon, some people taking Mektovi (binimetinib) with Braftovi (encorafenib) developed a heart condition that happens when the heart doesn’t pump as well. Some people with this heart problem might not feel anything. But others might have symptoms like tiredness, trouble breathing, and swelling in the legs.
Your provider will monitor how well your heart is pumping through imaging called an echocardiogram (echo). You’ll usually need imaging scans of your heart every 2 to 3 months while you’re taking Mektovi (binimetinib). You might need to pause or stop Mektovi (binimetinib) if the scans show that your heart isn’t pumping as well as it should or if you have related symptoms while you’re taking the medication.
A small number of people developed blood clots while they were taking Mektovi (binimetinib) and Braftovi (encorafenib). These blood clots can include those that happen in the arm or leg (deep vein thrombosis or DVT). More seriously, blood clots have also happened in the lung (pulmonary embolism or PE). Seek medical attention right away if you have sudden chest pain, trouble breathing, or swelling in one arm or leg. These can be signs that you have a blood clot.
Treatment with Mektovi (binimetinib) and Braftovi (encorafenib) can cause several different kinds of eye problems. The most commonly reported problem is a buildup of fluid in the back of the eye (serous retinopathy). This sometimes led to retinal detachment or macular edema. Though less common, some people also had blood clots in eye veins or swelling inside the eye. Your provider will check your vision or refer you to an ophthalmologist while you’re taking Mektovi (binimetinib). Tell your provider if you have any vision changes during treatment.
Though rare, some people taking Mektovi (binimetinib) with Braftovi (encorafenib) have had a serious lung problem called interstitial lung disease (ILD). Talk to your provider right away if you have sudden or worsening cough, trouble breathing, and fever. You might have to pause or stop Mektovi (binimetinib) while your provider figures out the cause.
Some people taking Mektovi (binimetinib) and Braftovi (encorafenib) together have had blood test results showing high levels of liver enzymes. These lab results can suggest liver problems. During treatment, your provider will monitor your liver health on a regular basis, usually every month. And if your levels are concerning, you might need to pause or stop Mektovi (binimetinib) while your provider looks into it.
Most people don’t feel any noticeable symptoms when they have high liver enzyme levels happens, so it’s important to keep up with your lab work regularly. Call your provider right away if you have stomach pain, yellowish skin, or yellow around the whites of your eyes, as these can be symptoms of liver problems.
Treatment with Mektovi (binimetinib) and Braftovi (encorafenib) can raise the level of creatine phosphokinase (CPK) in your blood. This can suggest that you have muscle damage. You’ll need to get blood work done periodically during treatment so your provider can keep track of your CPK levels. But let your provider know if you have muscle pain or very dark, reddish-brown urine, as this can be a sign of a rare muscle condition called rhabdomyolysis. Your provider might pause or stop Mektovi (binimetinib) depending on how severe your symptoms are.
Some people taking Mektovi (binimetinib) together with Braftovi (encorafenib) have experienced bleeding, usually in their gut. Tell your provider right away if you have blood in your stool, bleeding from your rectum, or bloody hemorrhoids. You might need to pause or stop Mektovi (binimetinib) while your provider looks into it.
Based on animal studies, Mektovi (binimetinib) might harm an unborn baby or raise the risk for miscarriage (pregnancy loss). Because of these risks, if you’re able to get pregnant, your provider might ask for a negative pregnancy test before you start taking Mektovi (binimetinib). Then, you should use birth control during treatment and for at least 30 days after the last dose. Let your provider know if you become pregnant during treatment.
The usual dose is 45 mg by mouth twice a day (about 12 hours apart).
Your dose might differ if you have moderate or severe liver problems. Your provider might also recommend taking a lower dose if you have certain side effects.
Melanoma with certain BRAF mutations that has spread (metastatic) or can’t be removed by surgery; used with Braftovi (encorafenib)
Metastatic non-small cell lung cancer (NSCLC) with certain BRAF mutations; used with Braftovi (encorafenib)
Melanoma with certain BRAF mutations that has spread (metastatic) or can’t be removed by surgery, used together with Zelboraf (vemurafenib)
Melanoma with certain BRAF mutations
Metastatic non-small cell lung cancer (NSCLC) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
Metastatic anaplastic thyroid cancer (ATC) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
Solid tumors with a certain BRAF mutation that have spread or can’t be removed by surgery, used with Tafinlar (dabrafenib)
Low-grade glioma (LGG) with a certain BRAF mutation, used with Tafinlar (dabrafenib)
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