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Erdafitinib (Oral)

Generic Name: erdafitinib (er-da-FI-ti-nib)

Medically reviewed by Last updated on Dec 29, 2020.

Commonly used brand name(s)

In the U.S.

  • Balversa

Available Dosage Forms:

  • Tablet

Therapeutic Class: Antineoplastic Agent

Pharmacologic Class: Tyrosine Kinase Inhibitor

Uses for erdafitinib

Erdafitinib is used to treat urothelial carcinoma (bladder cancer) that has spread or cannot be removed by surgery. It is used in patients who have an abnormal “FGFR” gene in their cancer and who have tried at least one other chemotherapy medicine that contains platinum that did not work well. Your doctor will test for the presence of this gene.

Erdafitinib is available only with your doctor's prescription.

Before using erdafitinib

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For erdafitinib, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to erdafitinib or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies have not been performed on the relationship of age to the effects of erdafitinib in the pediatric population. Safety and efficacy have not been established.


Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of erdafitinib in the elderly.


There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking erdafitinib, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using erdafitinib with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Alfentanil
  • Aluminum Carbonate, Basic
  • Aluminum Hydroxide
  • Aluminum Phosphate
  • Apalutamide
  • Bosentan
  • Calcium Acetate
  • Calcium Carbonate
  • Calcium Chloride
  • Calcium Citrate
  • Calcium Gluconate
  • Carbamazepine
  • Cholecalciferol
  • Cyclosporine
  • Dihydroergotamine
  • Dihydroxyaluminum Aminoacetate
  • Dihydroxyaluminum Sodium Carbonate
  • Dofetilide
  • Efavirenz
  • Enzalutamide
  • Ergocalciferol
  • Ergotamine
  • Etravirine
  • Fentanyl
  • Ferric Carboxymaltose
  • Ferric Citrate
  • Ferric Pyrophosphate Citrate
  • Ferrous Fumarate
  • Ferrous Gluconate
  • Ferrous Sulfate
  • Flibanserin
  • Fosphenytoin
  • Iron Dextran
  • Iron Sucrose
  • Lanthanum Carbonate
  • Lorlatinib
  • Lumacaftor
  • Magnesium Carbonate
  • Magnesium Hydroxide
  • Magnesium Oxide
  • Magnesium Trisilicate
  • Mitotane
  • Modafinil
  • Nafcillin
  • Oxycodone
  • Phenobarbital
  • Phenytoin
  • Pimavanserin
  • Pimozide
  • Potassium Phosphate
  • Primidone
  • Quinidine
  • Rifabutin
  • Rifampin
  • Sevelamer Carbonate
  • Sevelamer Hydrochloride
  • Sirolimus
  • Sodium Bicarbonate
  • Sodium Ferric Gluconate Complex
  • Sodium Phosphate
  • Sodium Phosphate, Dibasic
  • Sodium Phosphate, Monobasic
  • St John's Wort
  • Sucroferric Oxyhydroxide
  • Tacrolimus
  • Temsirolimus

Interactions with food/tobacco/alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems

The presence of other medical problems may affect the use of erdafitinib. Make sure you tell your doctor if you have any other medical problems, especially:

  • Eye or vision problems or
  • Hyperphosphatemia (high potassium levels in the blood)—Use with caution. May make these conditions worse.

Proper use of erdafitinib

Medicines used to treat cancer are very strong and can have many side effects. Before using erdafitinib, make sure you understand all the risks and benefits. It is important for you to work closely with your doctor during your treatment.

Take erdafitinib only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

Erdafitinib should come with a patient information leaflet. Read and follow these instructions carefully. Ask your doctor if you have any questions.

Swallow the tablet whole. You may take it with or without food.

You may use artificial tear substitutes or hydrating or lubricating eye gels or ointments, at least every 2 hours during waking hours to prevent or treat dry eyes.


The dose of erdafitinib will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of erdafitinib. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (tablets):
    • For blader cancer:
      • Adults—At first, 8 milligrams (mg) (two 4 mg tablets) once a day, then your doctor may increase your dose to 9 mg (three 3 mg tablets) once a day based on your phosphate levels at 14 to 21 days.
      • Children—Use and dose must be determined by your doctor.

Missed dose

If you miss a dose of erdafitinib, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

If you vomit after taking a dose, take the next dose at the regular time.


Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions while using erdafitinib

It is very important that your doctor check your progress at regular visits to make sure that erdafitinib is working properly and to check for unwanted effects.

Your doctor will give you a pregnancy test before you use erdafitinib to make sure you are not pregnant. Using erdafitinib while you are pregnant can harm your unborn baby. It may also cause birth defects if the father is using it when his sexual partner becomes pregnant. Female patients should use effective birth control during treatment with erdafitinib and for 1 month after the last dose. Male patients who have female partners should use effective birth control during treatment with erdafitinib and for 1 month after the last dose. If you think you have become pregnant while using erdafitinib, tell your doctor right away.

Check with your doctor right away if blurred vision, difficulty with reading, or any other change in vision occurs during or after treatment. Your doctor may want your eyes be checked by an ophthalmologist (eye doctor).

Erdafitinib may cause hyperphosphatemia (high potassium levels in the blood). Check with your doctor right away it you have stomach cramps, confusion, seizures, difficulty in breathing, irregular heartbeat, mood or mental changes, muscle cramps in the hands, arms, feet, legs, or face, numbness and tingling around the mouth, fingertips, or feet, or tremor.

If you plan to have children, talk with your doctor before using erdafitinib. Some women using erdafitinib have become infertile (unable to have children).

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Erdafitinib side effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

  • Bladder pain
  • bloody or cloudy urine
  • blurred vision
  • burning, dry, or itching eyes
  • confusion
  • difficult or labored breathing
  • difficult, burning, or painful urination
  • discharge
  • discoloration of the fingernails or toenails
  • excessive tearing
  • frequent urge to urinate
  • increased tearing
  • irregular heartbeat
  • loosening of the fingernails
  • lower back or side pain
  • mood or mental changes
  • muscle cramps in the hands, arms, feet, legs, or face
  • numbness and tingling around the mouth, fingertips, or feet
  • redness or soreness around the fingernails
  • redness, pain, or swelling of the eye, eyelid, or inner lining of the eyelid
  • redness, swelling, or pain of the skin
  • scaling of the skin on the hands and feet
  • seizures
  • stomach cramps
  • tightness in the chest
  • tremor
  • ulceration of the skin

Less common

  • Chest pain or discomfort
  • nausea
  • pain or discomfort in the arms, jaw, back, or neck
  • sweating
  • vomiting

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  • Bone pain
  • constipation
  • decreased appetite
  • diarrhea
  • difficulty in moving
  • dry mouth
  • dry skin
  • fever
  • hair loss or thinning of hair
  • joint pain
  • mouth or throat pain
  • muscle pain or stiffness
  • stomach pain
  • swelling or inflammation of the mouth
  • unusual tiredness or weakness
  • vomiting
  • weight decreased

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.