Elacestrant

Elacestrant is used to treat advanced hormone-related breast cancer in postmenopausal women and adult men when the cancer has progressed or spread to other parts of the body (metastatic) after other treatments have failed.

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

Elacestrant may also be used for reasons not mentioned in this medication guide.

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

Take elacestrant once a day at the same time each day.

Take elacestrant with food.

Do not change your dose or stop taking elacestrant without your doctor's advice.

Swallow the tablet whole and do not crush, chew, or break it. Do not use a broken tablet.

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

You will need frequent blood tests to check your cholesterol and triglycerides before and during treatment with elacestrant.

Store at room temperature away from moisture and heat.

Elacestrant can harm an unborn baby if either the mother or the father is using elacestrant.

• If you are a woman, use birth control while taking this medicine.
• If you are a man, use birth control if your sexual partner can get pregnant.

Tell your doctor if you have ever had:

• high cholesterol or triglycerides;
• liver disease.

Elacestrant can harm an unborn baby if either the mother or the father is using this medicine.

• If you are a woman, you may need a pregnancy test to ensure 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 sex partner can become pregnant. Continue using birth control for at least 1 week after your last dose.
• Inform your doctor immediately if a pregnancy occurs.

Elacestrant may affect fertility in men or women. It might be harder to achieve pregnancy while either parent is using this medicine.

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.

Common side effects of elacestrant may include:

• muscle and joint pain;
• nausea, vomiting, loss of appetite;
• increased cholesterol and triglyceride levels in your blood;
• abnormal kidney or liver function tests;
• headache;
• diarrhea, constipation;
• feeling tired;
• stomach pain, heartburn;
• low blood sodium;
• hot flush; or
• low red blood cells (anemia).

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

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.

Usual Adult Dose for Breast Cancer:

Recommended dose: 345 mg orally once a day with foodDuration of therapy: Until disease progression or unacceptable toxicityComments: -Select patients for treatment based on the presence of ESR1 mutations in plasma specimens using an FDA-approved test.Use: For the treatment of postmenopausal women or adult men with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, ESR1-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy.

Use the medicine as soon as you can, but skip the missed dose if you are more than 6 hours late for the dose. Use your next dose at the regular time. Do not use two doses at one time.

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

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

Sometimes, it is not safe to use certain medicines together. Some drugs can change the levels of other drugs in your blood, which may increase side effects or make the medicines less effective.

Other drugs may affect elacestrant, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you are using.