Emapalumab

Emapalumab is used in adults and children (including newborns) to treat:

• primary hemophagocytic lymphohistiocytosis (HLH) after the condition has returned or worsened, or if other treatments cannot be used, or if other treatments did not work or stopped working; and
• HLH/macrophage activation syndrome (MAS) in Still's disease (including systemic juvenile idiopathic arthritis) if a steroid cannot be taken, or if steroid medicine did not work, or when MAS has returned.

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

Emapalumab affects your immune system. You may get infections more easily, including serious or fatal infections. Call your doctor if you have a fever, chills, night sweats, skin sores, cough, trouble breathing, cough with bloody mucus, or any new or worsening signs of infection.

Before you start using emapalumab, tell your doctor if you have any signs of infection such as fever, chills, night sweats, cough, trouble breathing, cough with bloody mucus, or warm, red, or painful skin sores.

Tell your doctor if you've had or been exposed to tuberculosis, or if you recently traveled. Tuberculosis and certain fungal infections are more common in some parts of the world, and you may have been exposed during travel.

Tell your doctor if you have or have ever had:

• tuberculosis (or if anyone in your household has tuberculosis);
• a positive tuberculosis skin test;
• an active, chronic, or recent infection;
• histoplasmosis (a fungal infection);
• herpes zoster (also called shingles); or
• recently received or are scheduled to receive any vaccine.

It is not known if emapalumab will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Ask a doctor if it is safe to breastfeed while using emapalumab.

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

Some side effects may happen during the injection. Tell your medical caregiver if you feel dizzy, nauseous, light-headed, itchy, sweaty, or have a headache, chest tightness, back pain, trouble breathing, or swelling in your face.

You may get infections more easily, even serious or fatal infections. Call your doctor right away if you have signs of infection such as:

• fever, chills, night sweats;
• warm, red, or painful skin sores;
• cough, trouble breathing;
• blisters, itching, tingling, burning pain, rash on your face or torso;
• cough with bloody mucus; or
• any other new or worsening signs of infection.

Common side effects of emapalumab may include:

• fever;
• high blood pressure;
• infections (including viral); or
• skin rash.

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.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.

Before you receive emapalumab, your doctor will test you for tuberculosis or other infections.

Emapalumab is given as an infusion into a vein. A healthcare provider will give you this injection.

Your doctor will determine your treatment schedule and how long to treat you with this medicine.

Doses are based on weight. Your dose may change if you gain or lose weight.

You will be watched for a short time to make sure you do not have side effects that may occur during the injection.

You may get infections more easily, even serious or fatal infections. You will need frequent medical tests.

Your doctor will need to check your progress on a regular basis.

You may be given other medications to help treat your condition or prevent serious side effects. Keep taking these medicines for as long as your doctor has prescribed.

When you start or stop using emapalumab, your doctor may need to adjust the doses of other medicines you use on a regular basis.

Call your doctor for instructions if you miss an appointment for your Emapalumab infusion.

In a medical setting, an overdose would be treated quickly.

Do not receive a "live" vaccine while you are being treated with emapalumab, and for at least 4 weeks after your last dose. Live vaccines may include measles, mumps, rubella (MMR), varicella (chickenpox), nasal flu vaccine, and others.

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