Futibatinib

Futibatinib is a prescription medication used for previously treated, unresectable, locally advanced or metastatic intrahepatic cholangiocarcinoma in adults harboring fibroblast growth factor receptor 2 (FGFR2) gene fusions or other rearrangements.

• Futibatinib is available under the following different brand names: Lytgobi

Common side effects of Futibatinib include:

• nail toxicity
• musculoskeletal pain
• constipation
• diarrhea
• fatigue
• dry mouth
• hair loss
• stomatitis
• abdominal pain
• dry skin
• joint pain
• changes in taste
• dry eye
• nausea
• decreased appetite
• urinary tract infection (UTI)
• palmar-plantar erythrodysesthesia syndrome
• vomiting
• increased phosphate
• increased creatinine
• decreased hemoglobin
• increased glucose
• increased calcium
• decreased sodium
• decreased phosphate
• increased alanine aminotransferase
• increased alkaline phosphatase
• decreased lymphocytes
• increased aspartate aminotransferase
• decreased platelets
• increased activated partial thromboplastin time
• decreased leukocytes
• decreased albumin
• decreased neutrophils
• increased creatine kinase
• increased bilirubin
• decreased glucose
• increased prothrombin international normalized ratio
• decreased potassium

Serious side effects of Futibatinib include:

• hives
• difficulty breathing
• swelling of the face, lips, tongue, or throat
• vision loss
• reduced color vision
• blurry vision
• blind spot in the visual field
• muscle cramps or spasms
• numbness and tingling around the mouth
• bone and joint pain
• weak bones
• rash
• itching
• fever
• black or tarry stool
• vomiting blood
• abdominal cramping
• dizziness
• lightheadedness
• tiredness
• paleness
• shortness of breath
• fluid in the abdomen
• musculoskeletal pain
• bone calluses
• difficulty swallowing
• chest pain
• burning sensation in the mouth 
• abdominal pain (upper right side)
• dark urine
• yellowing of the skin and the whites of the eyes (jaundice)
• nausea
• vomiting
• clay-colored stools
• dizziness
• weakness
• loss of appetite
• swelling in the ankles and legs
• fatigue

Rare side effects of Futibatinib include:

• none 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, loss of coordination, feeling unsteady, very stiff muscles, high fever, profuse sweating, or tremors;
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out.

This is not a complete list of side effects and other serious side effects or health problems that may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult dosage

Tablet

• 4 mg

Cholangiocarcinoma

Adult dosage

• 20 mg orally every day
• Continue until disease progression or unacceptable toxicity occurs

Dosage Considerations – Should be Given as Follows:

• See "Dosages"

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, healthcare provider, or pharmacist first.

• Futibatinib has severe interactions with no other drugs.
• Futibatinib has serious interactions with the following drugs:
  • apalutamide
  • carbamazepine
  • clarithromycin
  • cobicistat
  • elvitegravir/cobicistat/emtricitabine/tenofovir DF
  • fosphenytoin
  • itraconazole
  • ketoconazole
  • levoketoconazole
  • nirmatrelvir/ritonavir
  • phenytoin
  • posaconazole
  • rifampin
  • ritonavir
  • tucatinib
• Futibatinibhas moderate interactions with the following drug:
  • lenacapavir
• Futibatinib has minor interactions with no other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all the products you use. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, or if you have health questions or concerns.

Contraindications

• None

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Futibatinib?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Futibatinib?”

Cautions

• Based on animal findings and its mechanism of action, fetal harm may occur in pregnant women
• Hyperphosphatemia
  • May cause hyperphosphatemia leading to soft tissue mineralization, calcinosis, nonuremic calciphylaxis, and vascular calcification
  • Increased phosphate levels are a pharmacodynamic effect of futibatinib
  • Monitor for hyperphosphatemia throughout the treatment
  • Initiate low phosphate diet and phosphate lowering therapy when serum phosphate level is 5.5 mg/dL and more
  • For serum phosphate levels higher than 7 mg/dL, initiate or intensify phosphate lowering therapy and reduce dose, withhold, or permanently discontinue based on duration and severity of hyperphosphatemia
• Retinal pigment epithelial detachment (RPED)
  • May cause RPED; symptoms include blurred vision
  • Perform comprehensive ophthalmologic examination, including optical coherence tomography of the macula, before initiating, every 2 mo for the first 6 mo, and every 3 mo thereafter
  • For the onset of visual symptoms, refer for ophthalmologic evaluation urgently, with follow-up every 3 wk until it resolves or therapy
  • Dry eye also occurred; treat with ocular demulcents as needed
• Drug interaction overview
• Substrate of CYP3A and P-glycoprotein (P-gp)
  • Inhibitor of P-gp and breast cancer resistance protein (BCRP)
• Dual P-gp and strong CYP3A inhibitors
• Avoid coadministration
  • Drugs that are dual P-gp and strong CYP3A inhibitors may increase futibatinib exposure and increase the risk for adverse reactions
• Dual P-gp and strong CYP3A inducers
• Avoid coadministration
  • Dual P-gp and strong CYP3A inducers may decrease futibatinib exposure and efficacy
• P-gp or BCRP substrates
  • Consider more frequent monitoring for adverse reactions associated with sensitive P-gp or BCRP substrates and reduce the dose of these drugs per their prescribing information
  • Futibatinib may increase the exposure of drugs that are substrates of P-gp or BCRP

Pregnancy and Lactation

• Based on an animal study and its mechanism of action, fetal harm or loss of pregnancy may occur when administered to pregnant women
• There are no available data on the use of futibatinib in pregnant women
• Verify the pregnancy status of women of reproductive potential before initiating
• Contraception
  • Women of reproductive potential: Use effective contraception during treatment and for 1 wk after the last dose
  • Men with women partners of reproductive potential or who are pregnant: Use effective contraception during treatment and for 1 wk after the last dose
• Lactation
  • There are no data on the presence of futibatinib or its metabolites in human milk or their effects on either breastfed infants or milk production
  • Advise women not to breastfeed during treatment and for 1 wk after the last dose