Cotellic (cobimetinib) is a targeted therapy that’s used to treat two different cancers in adults: histiocytic neoplasms and melanoma (a type of skin cancer). For histiocytic neoplasms, this medication is used by itself. But for melanoma, Cotellic (cobimetinib) is taken with another anticancer medication to treat people with a certain mutation called a BRAF mutation. Cotellic (cobimetinib) is convenient to take because it’s a tablet that you take by mouth. But it can cause side effects such as diarrhea, rash, and bleeding.
Melanoma with certain BRAF mutations that has spread (metastatic) or can’t be removed by surgery, used together with Zelboraf (vemurafenib)
Cotellic (cobimetinib) is a kinase inhibitor known as a MEK inhibitor. MEK is a protein in the body that’s important for cell growth. Cotellic (cobimetinib) works by blocking the MEK protein. When the medication blocks MEK, cancer cells can’t grow and spread as well.
For people with melanoma with a BRAF mutation, Cotellic (cobimetinib) is taken with Zelboraf (vemurafenib). The BRAF protein also helps cells grow, and cells can grow too quickly when there’s a BRAF mutation. By blocking two different proteins, Cotellic (cobimetinib) and vemurafenib (Zelboraf) work together to stop the growth and spread of cancer better.
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 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
Works in a more specific, targeted way than traditional chemotherapy
Recommended option for treating BRAF-mutated melanoma and for treating histiocytic neoplasms
Must take with a second medication if treating melanoma, so less convenient
Requires regular blood tests to monitor for side effects
Often causes diarrhea and skin sensitivity or rash
You can take Cotellic (cobimetinib) with or without food.
If you miss a dose of Cotellic (cobimetinib), skip the missed dose and wait to take the next scheduled dose.
If you have diarrhea while you’re taking Cotellic (cobimetinib), make sure you drink plenty of fluids. 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.
Some Cotellic (cobimetinib) side effects, such as anemia and changes in electrolyte levels in your blood, can only be found through blood testing. Your provider will order regular lab tests while you’re taking Cotellic (cobimetinib). These lab tests are important to make sure the medication is still safe for you to keep taking it.
Don't breastfeed while you're taking Cotellic (cobimetinib). We don’t know whether Cotellic (cobimetinib) 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 Cotellic (cobimetinib) and for 2 weeks after the last dose.
Ask your provider about the best way to handle and throw away Cotellic (cobimetinib) safely. Anticancer medications can be harmful to people who handle or come in contact with them. Store Cotellic (cobimetinib) in a safe place away from children and pets.
Cotellic (cobimetinib) 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.
Some people taking Cotellic (cobimetinib) together with Zelboraf (vemurafenib) developed a new cancer. In studies, these cancers included different kinds of skin cancer (squamous cell carcinoma, basal cell carcinoma, and melanoma). Zelboraf (vemurafenib) itself might also cause growth of other cancer types. Because people with melanoma who take Cotellic (cobimetinib) must also take Zelboraf (vemurafenib), there might be a risk for other cancer types as well. Your provider will monitor you for new signs and symptoms of cancer, especially skin cancers, while you’re taking Cotellic (cobimetinib).
Cotellic (cobimetinib), taken with or without Zelboraf (vemurafenib), can cause bleeding. This includes bleeding in the gut, blood in the urine, vaginal bleeding, and rarely, bleeding in the brain. If you have any unusual signs or symptoms of bleeding, tell your provider right away. If it’s mild, your provider might pause Cotellic (cobimetinib) and you might be able to restart it later at a lower dose. But sometimes the medication must be permanently stopped.
Some people taking Cotellic (cobimetinib) developed a heart condition where their heart doesn’t pump as well. Some people with this condition 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 before you start Cotellic (cobimetinib) and every 3 months while you’re taking it. If the scans show that your heart isn’t pumping as well as it should or if you experience related symptoms while you’re taking Cotellic (cobimetinib), you might need to pause or stop the medication.
Cotellic (cobimetinib) might cause skin issues, like dry skin, itchy skin, swelling around hair follicles (folliculitis), or rash. Most cases are mild, but there are some reports of severe rash that require hospitalization. If you have a new rash or skin problem, tell your provider. Based on how serious it is, you might need to pause or stop the medication.
Treatment with Cotellic (cobimetinib) 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). Sometimes, retinal detachment has also occurred. Rarely, some people had blood clots in eye veins. Your provider might refer you to an ophthalmologist while you’re taking Cotellic (cobimetinib). Tell your provider if you have any vision changes while taking Cotellic (cobimetinib).
Some people taking Cotellic (cobimetinib) have had blood test results showing high levels of liver enzymes in their blood, which can suggest liver problems. Your provider will monitor your liver health on a regular basis (usually every month). If your liver enzyme levels go up, you might need to pause or stop Cotellic (cobimetinib) while your provider looks into it. Most people don’t feel any noticeable symptoms when this happens, so it’s important to keep up with your lab work regularly. If you have stomach pain, yellowish skin, or yellow around the whites of your eyes, call your provider right away since these can be symptoms of liver damage.
Treatment with Cotellic (cobimetinib) 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 Cotellic (cobimetinib) depending on how severe your symptoms are.
People taking Cotellic (cobimetinib) with Zelboraf (vemurafenib) can develop photosensitivity, or skin that’s very sensitive to sunlight. In studies, some people developed sun sensitivity around 2 months after starting treatment, but it can also appear within days or even after several months of treatment. You should avoid sun exposure when possible. If you’re outdoors, wear sunscreen with an SPF of at least 30 and clothes that protect your skin. Let your provider know if you experience a sunburn or painful skin while taking Cotellic (cobimetinib).
Based on animal studies, Cotellic (cobimetinib) might harm an unborn baby or raise the risk for miscarriage (pregnancy loss). Because of this risk, people who can become pregnant should use birth control while taking Cotellic (cobimetinib) and for at least 2 weeks after the last dose. Let your provider know if you become pregnant during treatment.
The usual dose is 60 mg by mouth once a day for 3 weeks. Then, you’ll take 1 week off from the medication. This is considered one treatment cycle. Repeat the treatment cycle (3 weeks of treatment, followed by 1 week off) for as long as you’re taking the medication.
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 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
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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