Elexacaftor, ivacaftor, and tezacaftor

Elexacaftor, ivacaftor, and tezacaftor is a combination medicine used to treat cystic fibrosis in adults and children who are at least 2 years old.

elexacaftor, ivacaftor, and tezacaftor is intended only for patients with a specific gene mutation related to cystic fibrosis. You may need a medical test to confirm that you have this gene mutation.

Elexacaftor, ivacaftor, and tezacaftor may also be used for other purposes not mentioned in this medication guide.

Follow all instructions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

This medicine is usually taken twice a day, in the morning and in the evening (about 12 hours apart).

Always take this medicine with food that contains fat, such as butter, peanut butter, eggs, nuts, meat, whole milk, cheese, or yogurt.

Swallow the tablet whole and do not crush, chew, or break it.

Mix the granules with one teaspoon (5 mL) of soft food or liquid that is at room temperature, such as pureed fruits or vegetables, yogurt, applesauce, water, juice, or milk, and take it all at once within one hour.

Doses are based on weight in children and teenagers under 12 years old. Your child's dose may change if the child gains or loses weight.

Your dose may change if you also take certain other medications. Do not change your dose or dosing schedule without your doctor's advice.

You will need frequent blood tests to check your liver function.

A child using this medicine may need an eye exam before and after starting this treatment to check for cataracts.

Store at room temperature away from moisture and heat.

Use only as directed. Inform your doctor if you are using other medicines or have other medical conditions or allergies.

Some drugs should not be used with this medicine. Your treatment plan may change if you also use:

• rifabutin or rifampin;
• St. John's wort; or
• seizure medicine such as carbamazepine, phenobarbital, or phenytoin.

Tell your doctor if you have or have ever had:

• an allergy to any medication;
• liver disease; or
• kidney disease.

Tell your doctor if you are pregnant or breastfeeding.

Get emergency medical help if you have signs of an allergic reaction: hives, difficulty breathing, swelling of your face, lips, tongue, or throat.

Elexacaftor, ivacaftor, and tezacaftor may cause serious side effects. Call your doctor right away if you have:

• vision changes; or
• liver problems—loss of appetite, stomach pain (upper right side), tiredness, itching, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Common side effects of elexacaftor, ivacaftor, and tezacaftor may include:

• headache;
• diarrhea, stomach pain;
• rash;
• abnormal lab tests;
• flu symptoms such as fever, chills, body aches; or
• cold symptoms such as stuffy nose, sinus pain, sneezing, sore throat.

This is not a complete list of side effects, and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Take the medicine as soon as you can, but do not take two doses at once.

If you are more than 6 hours late in taking the morning dose, take it as soon as you can but skip the evening dose for that day.

If you are more than 6 hours late in taking the evening dose, skip that missed dose and take the morning dose at the regular time the next day.

Make sure to take a missed dose with a food that has fat in it.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

• Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired.

• Grapefruit may interact with this medicine and cause side effects. Avoid consuming grapefruit products.

Sometimes, it is not safe to take certain medicines together. Some drugs can change how much of another drug is in your blood, which can increase side effects or make the medicines work less effectively.

Tell your doctor about all the other medicines you are taking, especially:

• an antibiotic--clarithromycin, erythromycin, telithromycin; or
• antifungal medicine--fluconazole, ketoconazole, itraconazole, posaconazole, voriconazole.

This list is not complete. Other drugs may also affect this medicine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are mentioned here.