Pralsetinib is used to treat non-small cell lung cancer that has spread to other parts of the body (metastatic).

Pralsetinib is used only if your cancer has a specific genetic marker (an abnormal "RET" gene fusion). Your doctor will test you for this gene fusion.

Pralsetinib was approved by the US Food and Drug Administration (FDA) on an "accelerated" basis. In clinical studies, some people responded to pralsetinib, but further studies are needed.

Pralsetinib may also be used for purposes not listed in this medication guide.

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

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

Take pralsetinib on an empty stomach, at least 1 hour before or 2 hours after a meal.

If you vomit shortly after taking pralsetinib, do not take another dose. Wait until your next scheduled dose time to take the medicine again.

Your blood pressure will need to be checked often and you will need frequent blood tests.

If you need surgery, tell your surgeon you currently use this medicine. You may need to stop for a short time.

Do not change your dose or stop using a medicine without your doctor's advice.

Store at room temperature away from moisture and heat.

Usual Adult Dose for Non-Small Cell Lung Cancer:

400 mg orally once a day
Duration of therapy: Continue until disease progression or unacceptable toxicity

Comments:
-Select patients based on the presence of a RET (rearranged during transfection) gene fusion.
-Information on FDA-approved tests for RET gene fusion is available at http://www.fda.gov/CompanionDiagnostics.

Use: For the treatment of metastatic RET fusion-positive non-small cell lung cancer (NSCLC) as detected by an FDA approved test.

Usual Adult Dose for Thyroid Cancer:

400 mg orally once a day
Duration of therapy: Continue until disease progression or unacceptable toxicity

Comments:
-Select patients based on the presence of a RET (rearranged during transfection) gene fusion (thyroid cancer) or RET gene mutation (MTC).
-However, FDA-approved gene fusion tests for RET gene fusion (thyroid cancer) and RET gene mutations are currently not available.

Uses:
-For the treatment of advanced or metastatic RET mutant medullary thyroid cancer (MTC) who require systemic therapy.
-For the treatment of advanced or metastatic RET fusion-positive thyroid cancer who require systemic therapy and who are radioactive iodine-refractory (if radioactive iodine is appropriate).

Usual Pediatric Dose for Thyroid Cancer:

12 years or older: 400 mg orally once a day
Duration of therapy: Continue until disease progression or unacceptable toxicity

Comments:
-Select patients based on the presence of a RET (rearranged during transfection) gene fusion (thyroid cancer) or RET gene mutation (MTC).
-However, FDA-approved gene fusion tests for RET gene fusion (thyroid cancer) and RET gene mutations are currently not available.

Uses:
-For the treatment of advanced or metastatic RET mutant medullary thyroid cancer (MTC) who require systemic therapy.
-For the treatment of advanced or metastatic RET fusion-positive thyroid cancer who require systemic therapy and who are radioactive iodine-refractory (if radioactive iodine is appropriate).

Tell your doctor if you have ever had:

• lung or breathing problems other than lung cancer;

• bleeding problems; or

• high blood pressure.

Pralsetinib can harm an unborn baby if the mother or the father is using pralsetinib.

• If you are a woman, do not use pralsetinib if you are pregnant. You may need to have a negative pregnancy test before starting this treatment. Use effective non-hormonal birth control to prevent pregnancy while you are using this medicine and for at least 2 weeks after your last dose.

• If you are a man, use effective birth control if your sex partner is able to get pregnant. Keep using birth control for at least 1 week after your last dose.

• Tell your doctor right away if a pregnancy occurs while either the mother or the father is using pralsetinib.

Pralsetinib can make hormonal birth control less effective, including birth control pills, injections, implants, skin patches, and vaginal rings. To prevent pregnancy while using pralsetinib, use a barrier form of birth control: condom, diaphragm, cervical cap, or contraceptive sponge.

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

Pralsetinib is not approved for use by anyone younger than 18 years old.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

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

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

Unless your doctor tells you otherwise, continue your normal diet.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

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

Pralsetinib may cause serious side effects. Call your doctor at once if you have:

• fever, chills;

• new or worsening cough, shortness of breath, or chest pain;

• severe headache, dizziness, confusion, trouble speaking;

• any wound that will not heal;

• unusual bleeding--bruising, nosebleeds, bleeding gums, abnormal vaginal bleeding, any bleeding that will not stop;

• signs of bleeding inside your body--weakness, drowsiness, pink or brown urine, bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds;

• low blood cell counts--fever, tiredness, sore throat, mouth sores, skin sores, pale skin, cold hands and feet, feeling light-headed or short of breath; or

• liver problems--nausea, vomiting, loss of appetite, stomach pain (upper right side), tiredness, dark urine, jaundice (yellowing of the skin or eyes).

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

Common side effects of pralsetinib may include:

• high blood pressure;

• low blood cell counts or other abnormal laboratory tests;

• muscle or joint pain;

• feeling tired; or

• constipation.

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.

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Tell your doctor about all your current medicines. Many drugs can affect pralsetinib, especially:

• an antibiotic or antifungal medicine;

• antiviral medicine to treat HIV or hepatitis C;

• cancer medicine;

• certain cholesterol medicines; or

• seizure medicine.

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

Keep all appointments with your doctor and the laboratory. Your doctor will order a lab test before your treatment to find out if your cancer can be treated with pralsetinib. Your doctor will also order certain lab tests before, during, and after your treatment to check your body's response to pralsetinib.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.