Futibatinib

Futibatinib is used in adults to treat bile duct cancer that has spread (metastatic) or cannot be removed by surgery:

• in patients who have already received another treatment; and
• in patients whose tumor has an abnormal "FGFR2" gene.

Your doctor will confirm that you have the right tumor type to be treated with futibatinib.

Futibatinib may also be used for other purposes not mentioned in this medication guide.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

You may take futibatinib once a day with or without food at about the same time.

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

If you vomit shortly after taking futibatinib, do not take another dose. Take your next dose as scheduled.

Your futibatinib treatments may be delayed or permanently discontinued if you have certain side effects.

You will need to see an eye specialist before you start using futibatinib, every 2 months for the first 6 months, and then every 3 months thereafter while you are using this medicine.

You may need to follow a special diet. Follow all instructions of your doctor or dietitian. Learn about the foods you should eat or avoid.

Your blood will need to be tested during treatment with futibatinib.

You should use artificial tears or lubricating eye gels during treatment with futibatinib.

Store at room temperature away from moisture and heat.

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

Tell your doctor if you have:

• vision or eye problems.

Futibatinib can harm an unborn baby if the mother or the father is using futibatinib.

• If you are a woman, you may need a pregnancy test to confirm you are not pregnant. Use birth control while taking this medicine and for at least 1 week after your last dose.
• If you are a man, use birth control if your sexual partner can become pregnant. Continue using birth control for at least 1 week after your last dose.
• Inform your doctor immediately if you become pregnant.

Do not breastfeed while taking this medicine, and for at least 1 week after your last dose.

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

Futibatinib may cause serious side effects. Call your doctor right away if you have:

• changes in your vision, including blurred vision, seeing flashes of light, or black spots;
• muscle cramps; or
• numbness or tingling around your mouth.

Common side effects of futibatinib may include:

• stomach pain, nausea, vomiting, constipation, diarrhea, loss of appetite;
• dry mouth, skin, or eyes;
• pain and burning when you urinate;
• tiredness or weakness;
• redness, swelling, pain, or blisters on the palms of your hands or the soles of your feet;
• muscle or joint pain;
• changes in your sense of taste;
• change in the appearance or color of nails;
• hair loss;
• abnormal lab tests;
• high blood sugar--increased thirst, increased urination, dry mouth, fruity breath odor;
• low blood sugar--headache, hunger, sweating, irritability, dizziness, fast heart rate, and feeling anxious or shaky;
• low blood potassium--leg cramps, constipation, irregular heartbeats, fluttering in your chest, increased thirst or urination, numbness or tingling, muscle weakness or feeling limp;
• high calcium levels--confusion, tiredness, nausea, vomiting, loss of appetite, constipation, increased thirst or urination, weight loss;
• low blood sodium--headache, confusion, problems with thinking or memory, weakness, feeling unsteady; or
• low blood cell counts--fever, chills, tiredness, mouth sores, skin sores, easy bruising, unusual bleeding, pale skin, cold hands and feet, feeling light-headed or short of breath.

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 the FDA at 1-800-FDA-1088.

Usual Adult Dose for Cholangiocarcinoma of biliary tract:

20 mg orally once a day (five 4 mg tablets or one 16 mg tablet plus one 4 mg tablet)Duration of therapy: Until disease progression or unacceptable toxicityComments:-Confirm the presence of a fibroblast growth factor receptor 2 (FGFR2) gene fusion or other rearrangement before starting treatment.Use: For the treatment of patients with previously treated, unresectable, locally advanced or metastatic intrahepatic cholangiocarcinoma with an FGFR2 gene fusion or other rearrangement

Use the medicine as soon as you can, but skip the missed dose if you are more than 12 hours late for the dose. Do not use two doses at one time.

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

Grapefruit may interact with futibatinib and cause side effects. Avoid consuming grapefruit products.

Tell your doctor about all your other medicines, especially:

• itraconazole; or
• rifampin.

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