Jump To


Generic name: cobimetinib
Brand name: Cotellic
Dosage form: oral tablet (20 mg)
Drug class: Multikinase inhibitors

Medically reviewed by  A Ras MD.

What is cobimetinib?

Cobimetinib is a prescription medicine that is used to treat a type of skin cancer (melanoma).


Cobimetinib fumarate is a kinase inhibitor. The chemical name is (S)-[3,4-difluoro-2-(2-fluoro-4-iodophenylamino)phenyl] [3-hydroxy-3-(piperidin-2-yl)azetidin-1-yl]methanone hemifumarate. It has a molecular formula C46H46F6I2N6O(2 C21H21F3IN3O2 ∙ C4H4O4) with a molecular mass of 1178.71 as a fumarate salt. Cobimetinib fumarate has the following chemical structure:

Chemical Structure

Cobimetinib is a fumarate salt appearing as white to off-white solid and exhibits a pH dependent solubility.

COTELLIC (cobimetinib) tablets are supplied as white, round, film-coated 20 mg tablets for oral administration, debossed on one side with “COB”. Each 20 mg tablet contains 22 mg of cobimetinib fumarate, which corresponds to 20 mg of the cobimetinib free base.

The inactive ingredients of COTELLIC are: Tablet Core: microcrystalline cellulose, lactose monohydrate, croscarmellose sodium, magnesium stearate. Coating: polyvinyl alcohol, titanium dioxide, polyethylene glycol 3350, talc.

 Mechanism of Action

Cobimetinib is a reversible inhibitor of mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase 1 (MEK1) and MEK2. MEK proteins are upstream regulators of the extracellular signal-related kinase (ERK) pathway, which promotes cellular proliferation. BRAF V600E and K mutations result in constitutive activation of the BRAF pathway which includes MEK1 and MEK2. In mice implanted with tumor cell lines expressing BRAF V600E, cobimetinib inhibited tumor cell growth.

Cobimetinib and vemurafenib target two different kinases in the RAS/RAF/MEK/ERK pathway. Compared to either drug alone, coadministration of cobimetinib and vemurafenib resulted in increased apoptosis in vitro and reduced tumor growth in mouse implantation models of tumor cell lines harboring BRAF V600E mutations. Cobimetinib also prevented vemurafenib-mediated growth enhancement of a wild-type BRAF tumor cell line in an in vivo mouse implantation model.

Before taking cobimetinib, tell your doctor:

  • If you are allergic to cobimetinib; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you take any drugs (prescription or OTC, natural products, vitamins) that must not be taken with cobimetinib, like certain drugs that are used for HIV, infections, or seizures. There are many drugs that must not be taken with cobimetinib.
  • If you are taking St. John’s wort. Do not take St. John’s wort with cobimetinib. This medicine may not work as well.
  • If you are breast-feeding. Do not breast-feed while you take cobimetinib and for 2 weeks after your last dose.

This is not a list of all drugs or health problems that interact with cobimetinib.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take cobimetinib with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take cobimetinib?

  • Tell all of your health care providers that you take cobimetinib. This includes your doctors, nurses, pharmacists, and dentists.
  • This medicine is used with vemurafenib. Talk with the doctor about the risks and side effects that may happen with vemurafenib.
  • This medicine may add to the chance of getting some types of cancer. Talk with the doctor.
  • You will need to have a skin exam before you start cobimetinib and every 2 months while you take it. You will also need to do monthly skin checks as told by your doctor.
  • Have an eye exam as you have been told by your doctor.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • You may get sunburned more easily. Avoid sun, sunlamps, and tanning beds. Use sunscreen and wear clothing and eyewear that protects you from the sun.
  • High blood pressure has happened with cobimetinib. Have your blood pressure checked as you have been told by your doctor.
  • This medicine may cause heart failure. You will need to have your heart function checked while taking cobimetinib. Call your doctor right away if you have signs of heart problems like a cough or shortness of breath that is new or worse, swelling of the ankles or legs, a heartbeat that does not feel normal, weight gain of more than 5 pounds in 24 hours, dizziness, or passing out.
  • A certain muscle problem (rhabdomyolysis) has happened with cobimetinib. Rarely, this has led to organ problems and death. Call your doctor right away if you have muscle pain or weakness.
  • This medicine may affect fertility. Fertility problems may lead to not being able to get pregnant or father a child.
  • Use birth control that you can trust to prevent pregnancy while taking cobimetinib and for at least 2 weeks after stopping the drug.
  • This medicine may cause harm to the unborn baby if you take it while you are pregnant.
  • If you get pregnant while taking cobimetinib or within 2 weeks after your last dose, call your doctor right away.

How is cobimetinib best taken?

Use cobimetinib as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Take with or without food.
  • If you throw up after taking a dose, do not repeat the dose. Take your next dose at your normal time.
  • Keep taking cobimetinib as you have been told by your doctor or other health care provider, even if you feel well.

What do I do if I miss a dose?

  • Skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

What are the side effects of cobimetinib that I need to call my doctor about immediately?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of bleeding like throwing up or coughing up blood; vomit that looks like coffee grounds; blood in the urine; black, red, or tarry stools; bleeding from the gums; abnormal vaginal bleeding; bruises without a cause or that get bigger; or bleeding you cannot stop.
  • Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • Signs of electrolyte problems like mood changes, confusion, muscle pain or weakness, a heartbeat that does not feel normal, seizures, not hungry, or very bad upset stomach or throwing up.
  • Signs of high blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
  • Weakness on 1 side of the body, trouble speaking or thinking, change in balance, drooping on one side of the face, or blurred eyesight.
  • Dizziness.
  • Feeling tired or weak.
  • Stomach pain.
  • Headache.
  • A skin lump or growth.
  • Change in eyesight, eye pain, or very bad eye irritation.
  • Loss of eyesight.
  • Seeing halos or bright colors around lights.
  • Fever or chills.
  • Sunburn.
  • Skin irritation.
  • Bumps, thick, dry, or wrinkled skin.
  • Red, painful, or itchy skin that is hot to touch.
  • Have your skin checked. Tell your doctor if you have any skin changes like a new wart, skin sore or reddish bump that bleeds or does not heal, or a change in the color or size of a mole.

What are some other side effects of cobimetinib?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Diarrhea.
  • Pimples (acne).
  • Upset stomach or throwing up.
  • Mouth irritation or mouth sores.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out cobimetinib?

  • Store at room temperature.
  • Store in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.




  • NDC 50242-717-01
  • Cotellic®
  • 20 mg
  • Rx only
  • 63 tablets
  • 10176377
PRINCIPAL DISPLAY PANEL - 63 Tablet Bottle Label


Read Next Article

PHP Code Snippets Powered By : XYZScripts.com