Cobimetinib

Other Names: Cotellic®

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About This Drug

Cobimetinib is used to treat cancer. It is given orally (by mouth).

Possible Side Effects

  • A decrease in the number of white blood cells, which may increase your risk of infection.
  • A decrease in the number of red blood cells, which may make you feel tired and weak (fatigue).
  • Nausea and vomiting (throwing up)
  • Diarrhea (loose bowel movements)
  • Fever
  • Changes in your liver function
  • Electrolyte changes
  • Increase in creatine phosphokinase (CPK), which can sometimes be the result of muscle inflammation or damage. You may have muscle aching and/or cramping.
  • Sensitivity to sunlight/light. You may get a skin rash/reaction while being out in the sun, sun lamps and tanning beds.

Note: Each of the side effects above was reported in 20% or greater of patients treated with cobimetinib. Not all possible side effects are included above.

Warnings and Precautions

  • Blurred vision or other changes in eyesight
  • Changes in the tissue of the heart. Some changes may happen that can cause your heart to have less ability to pump blood.
  • Severe allergic skin reaction. You may develop blisters on your skin that are filled with fluid or a severe red rash all over your body that may be painful.
  • Abnormal bleeding – symptoms may be coughing up blood, throwing up blood (may look like coffee grounds), red or black tarry bowel movements, abnormally heavy menstrual flow, nosebleeds or any other unusual bleeding.
  • Severe changes in your liver function
  • Rhabdomyolysis- damage to your muscles which may release proteins in your blood and affect how your kidneys work. You may have severe muscle weakness (lack of muscle strength). • Severe sensitivity to sunlight/light.
  • This drug may raise your risk of getting a skin cancer

Note: Some of the side effects above are very rare. If you have concerns and/or questions, please discuss them with your medical team. 

How to Take Your Medication

  • Swallow the medicine whole with or without food. Do not chew, break, cut or crush it.
  • Missed dose: If you vomit or miss a dose, take your next dose at the regular time. Do not take 2 doses at the same time, instead, continue with your regular dosing schedule and contact your physician.
  • Handling: Wash your hands after handling your medicine, your caretakers should not handle your medicine with bare hands and should wear latex gloves.
  • This drug may be present in the saliva, tears, sweat, urine, stool, vomit, semen, and vaginal secretions. Talk to your doctor and/or your nurse about the necessary precautions to take during this time.
  • Storage: Store this medicine in the original container at room temperature.
  • Disposal of unused medicine: Do not flush any expired and/or unused medicine down the toilet or drain unless you are specifically instructed to do so on the medication label. Some facilities have take-back programs and/or other options. If you do not have a take-back program in your area, then please discuss with your nurse or your doctor how to dispose of unused medicine. 

Treating Side Effects

  • Manage tiredness by pacing your activities for the day.
  • Be sure to include periods of rest between energy-draining activities
  • To decrease the risk of infection, wash your hands regularly.
  • Avoid close contact with people who have a cold, the flu, or other infections.
  • Take your temperature as your doctor or nurse tells you, and whenever you feel like you may have a fever.
  • Drink plenty of fluids (a minimum of eight glasses per day is recommended).
  • If you throw up or have loose bowel movements, you should drink more fluids so that you do not become dehydrated (lack of water in the body from losing too much fluid).
  • If you have diarrhea, eat low-fiber foods that are high in protein and calories and avoid foods that can irritate your digestive tracts or lead to cramping.
  • Ask your nurse or doctor about medicine that can lessen or stop your diarrhea.
  • To help with nausea and vomiting, eat small, frequent meals instead of three large meals a day. Choose foods and drinks that are at room temperature. Ask your nurse or doctor about other helpful tips and medicine that is available to help stop or lessen these symptoms.
  • Use sunscreen and lip balm with SPF 30 or higher when you are outdoors even for a short time. Cover up when you are out in the sun. Wear wide-brimmed hats, long-sleeved shirts, and pants. Keep your neck, chest, and back covered.
  • If you get a rash do not put anything on it unless your doctor or nurse says you may. Keep the area around the rash clean and dry. Ask your doctor for medicine if your rash bothers you.

Food and Drug Interactions

  • There are no known interactions of cobimetinib with food.
  • Check with your doctor or pharmacist about all other prescription medicines and over-the-counter medicines and dietary supplements (vitamins, minerals, herbs and others) you are taking before starting this medicine as there are known drug interactions with cobimetinib. Also, check with your doctor or pharmacist before starting any new prescription or over-the-counter medicines, or dietary supplements to make sure that there are no interactions.
  • Avoid the use of St. John’s Wort while taking cobimetinib as this may lower the levels of the drug in your body, which can make it less effective.

When to Call the Doctor

Call your doctor or nurse if you have any of these symptoms and/or any new or unusual symptoms: 

  • Fever of 100.4° F (38° C) or higher
  • Chills
  • Tiredness that interferes with your daily activities
  • Feeling dizzy or lightheaded
  • Easy bleeding or bruising
  • Blood in your urine, vomit (bright red or coffee-ground) and/or stools (bright red, or black/tarry)
  • Coughing up blood
  • Unexplained muscle pain, tenderness, or weakness
  • Blurred vision or other changes in eyesight
  • Trouble breathing
  • Swelling of arms, hands, legs and/or feet
  • Weight gain of 5 pounds in one week (fluid retention)
  • Feeling that your heart is beating in a fast or not normal way (palpitations)
  • Pain in your chest
  • Nausea that stops you from eating or drinking and/or is not relieved by prescribed medicines
  • Throwing up more than 3 times a day
  • Diarrhea, 4 times in one day or diarrhea with lack of strength or a feeling of being dizzy
  • Decreased urine, or very dark urine, muscle pain in the shoulders, thighs, or lower back; muscle weakness or trouble moving arms and legs
  • A new rash or a rash that is not relieved by prescribed medicines
  • Changes in your skin, or new skin lesions
  • Develop sensitivity to sunlight/light
  • Extreme muscle weakness that interferes with normal activities
  • Signs of possible liver problems: dark urine, pale bowel movements, bad stomach pain, feeling very tired and weak, unusual itching, or yellowing of the eyes or skin
  • If you think you may be pregnant

Reproduction Warnings

  • Pregnancy warning: This drug can have harmful effects on the unborn baby. Women of childbearing potential should use effective methods of birth control during your cancer treatment and for at least 2 weeks after treatment. Let your doctor know right away if you think you may be pregnant
  • Breastfeeding warning: Women should not breastfeed during treatment and for 2 weeks after treatment because this drug could enter the breast milk and cause harm to a breastfeeding baby.
  • Fertility warning: In men and women both, this drug may affect your ability to have children in the future. Talk with your doctor or nurse if you plan to have children. Ask for information on sperm or egg banking.

Revised June 2019

This patient information was developed by Via Oncology, LLC © 2019. This information is not intended to be used as a substitute for professional medical advice, diagnosis, or treatment. You should not rely entirely on this information for your health care needs. Ask your own doctor or health care provider any specific medical questions that you have. CLIENT acknowledges that the Via Pathways and Via Portal are information management tools only, and that Via Oncology, LLC has not represented the Via Pathways or Via Portal as having the ability to diagnose disease, prescribe treatment, or perform any other tasks that constitute the practice of medicine. The clinical information contained in the Via Pathways and Via Portal are intended as a supplement to, and not a substitute for, the knowledge, expertise, skill, and judgment of physicians, pharmacists and other healthcare professionals involved with patient care at CLIENT facilities.