Erdafitinib

Erdafitinib is a prescription medication used for the treatment of urothelial cancer.

• Erdafitinib is available under the following different brand names: Balversa

Common side effects of Erdafitinib include:

• dry eyes,
• puffy eyelids,
• dry mouth,
• mouth sores,
• hair loss,
• dry skin,
• problems with the fingernails or toenails,
• pain, redness, numbness, and peeling skin on the hands or feet,
• muscle pain,
• tiredness,
• abnormal liver or kidney function tests,
• low sodium levels,
• low red blood cell count,
• nausea,
• stomach pain,
• loss of appetite,
• diarrhea,
• constipation, and
• changes in the sense of taste

Serious side effects of Erdafitinib include:

• hives,
• difficulty breathing,
• swelling of the face, lips, tongue, or throat,
• numbness or tingling around the mouth,
• muscle stiffness,
• body aches,
• itching,
• rash,
• tiredness,
• trouble sleeping,
• nausea,
• vomiting,
• loss of appetite,
• shortness of breath,
• vision problems,
• vision loss,
• eye pain or redness,
• painful or irritated eyelids,
• feeling like something is in the eye,
• watery eyes,
• increased sensitivity to light,
• pain or bleeding from the finger or toenails,
• separation of the nails from the skin (nail bed),
• unusual breakage of the nails,
• changes in nail color or texture, and
• cracks or infections in the cuticles

Rare side effects of Erdafitinib 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 because 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

• 3 mg
• 4 mg
• 5 mg

Urothelial Carcinoma

Adult dosage

• 8 mg orally every day initially; increase to 9 mg orally every day based on serum phosphate (PO4) levels and tolerability at 14-21 days
• Continue until disease progression or unacceptable toxicity
• Increase the dose to 9 mg every day if the serum phosphate level is less than 5.5 mg/dL and there are no ocular disorders or Grade above 2 adverse reactions

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, health care provider, or pharmacist first.

• Erdafitinib has severe interactions with no other drugs.
• Erdafitinib has serious interactions with at least 165 other drugs.
• Erdafitinib has moderate interactions with at least 30 other drugs.
• Erdafitinib has minor interactions with the following drug:
  • encorafenib

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 your products. 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 Erdafitinib?”

Long-Term Effects

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

Cautions

• Based on the mechanism of action and animal studies, can cause fetal harm if administered to pregnant women
• Ocular disorders
  • Can cause ocular disorders, including central serous retinopathy/retinal pigment epithelial detachment (CSR/RPED), resulting in a visual-field defect
  • Perform monthly ophthalmological examinations during the first 4 months of treatment and then every 3 months afterward, and urgently at any time for visual symptoms
  • Dry eye symptoms are common; all patients should receive dry eye prophylaxis with ocular demulcents as needed
• Hyperphosphatemia
  • Can cause hyperphosphatemia leading to soft tissue mineralization, cutaneous calcinosis, non-uremic calciphylaxis, and vascular calcification
  • Increases in serum phosphate levels are a pharmacodynamic effect as a consequence of FGFR inhibition
  • Median onset time for any grade event of hyperphosphatemia was 20 days
  • Monitor for hyperphosphatemia and follow dose modifications when required
  • Patients may require phosphate binders during treatment
• Drug interaction overview

Moderate CYP2C9 or strong CYP3A4 inhibitors

• Coadministration increases erdafitinib plasma concentrations
• Consider alternant therapies
• If coadministration is unavoidable, monitor closely for adverse reactions and consider dose modifications accordingly
• If the moderate CYP2C9 or strong CYP3A4 inhibitor is discontinued, erdafitinib dose may be increased
• Strong CYP2C9 or CYP3A4 inducers
  • Coadministration may significantly decrease erdafitinib plasma concentrations and efficacy
  • Avoid coadministration
• Moderate CYP2C9 or CYP3A4 inducers
  • Coadministration may significantly decrease erdafitinib plasma concentrations and efficacy
  • If moderate inducer must be coadministered at the start of treatment, start at 8-mg/day dose, with the potential to increase to 9 mg/day based on serum phosphate levels on Days 14-21 and tolerability
  • If moderate inducer must be coadministered after the initial dose increase period based on serum phosphate levels and tolerability, increase erdafitinib dose up to 9 mg
  • When a moderate inducer is discontinued, continue erdafitinib at the same dose, in absence of drug-related toxicity
• Serum phosphate level-altering drugs
  • Coadministration with other serum phosphate level-altering agents may increase or decrease serum phosphate levels
  • Avoid coadministration before the initial dose increase period (Days 14-21)
• CYP3A4 substrates
  • Erdafitinib may alter plasma concentrations of CYP3A4 substrates, leading to either loss of activity or increased toxicity of the substrate
  • Avoid coadministration with sensitive CYP3A4 substrates with narrow therapeutic indices
• OCT2 substrates
  • Erdafitinib may increase plasma concentrations of OCT2 substrates
  • Consider alternant therapies
• P-gp substrates
  • Erdafitinib may increase plasma concentrations of P-gp substrates
  • If coadministration is unavoidable, separate administration by at least 6 hr before or after administration of P-gp substrates with a narrow therapeutic index

Pregnancy and Lactation

• Based on the mechanism of action and findings in animal reproduction studies, can cause fetal harm when administered to pregnant women
• Animal studies: Administration to pregnant rats during organogenesis caused malformations and embryofetal death at maternal exposures that were less than the human exposures at the maximum recommended human dose based on AUC
• Pregnancy testing is recommended for females of reproductive potential before initiating erdafitinib
• Infertility: Based on findings in animal studies, may impair fertility in females of reproductive potential
• Contraception
  • Females: Advise females of reproductive potential to use effective contraception during treatment and for 1 month after the last dose
  • Males: Advise male patients with female partners of reproductive potential to use effective contraception during treatment and for 1 month after the last dose
• Lactation
  • No data are available on the presence in human milk, its effects on breastfed children, or milk production
  • Owing to the potential serious adverse reactions in breastfed children, advise lactating women not to breastfeed during treatment and for 1 month following the last dose