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Important Safety Information

What is SYLVANT?

SYLVANT® (siltuximab) is a prescription medicine used to treat people with multicentric Castleman’s disease (MCD) who do not have human immunodeficiency virus (HIV) and human herpesvirus-8 (HHV-8) infection. It is not known if SYLVANT is safe and effective in children.

Who should not take SYLVANT?

Do not take SYLVANT if you have had a severe allergic reaction to siltuximab or any of the ingredients in SYLVANT. See the Medication Guide for a complete list of ingredients in SYLVANT.

What are the possible side effects of SYLVANT?

SYLVANT may cause serious side effects, including:

Infections. SYLVANT may lower your ability to fight infections. Tell your healthcare provider right away if you have any signs or symptoms of an infection during treatment with SYLVANT.

Infusion and allergic reactions. If you have an infusion or allergic reaction while receiving SYLVANT, your healthcare provider will stop your infusion and treat your reaction. If you have a severe infusion or allergic reaction, your healthcare provider may stop your treatment completely. Tell your healthcare provider or get medical help right away if you have any of these symptoms during or after your infusion of SYLVANT:

  • back pain
  • chest pain or tightness
  • nausea and vomiting
  • flushing
  • redness
  • irregular heart beat (palpitations)
  • trouble breathing
  • wheezing
  • dizziness or light-headedness
  • swelling of the lips
  • skin rash
  • headache
  • itching

The most common side effects of SYLVANT include:

rash, itching, upper respiratory tract infection, swelling, weight gain, and increased blood level of uric acid.

These are not all the possible side effects of SYLVANT. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Before you take SYLVANT, tell your healthcare provider about all of your medical conditions, including if you:

  • have an infection. You should not take SYLVANT if you have a severe infection.
  • have had a recent vaccination or are scheduled to receive any vaccinations. You should not receive a live vaccine during your treatment with SYLVANT.
  • have or have had any stomach or bowel (intestine) problems, such as diverticulitis or ulcers. Tell your healthcare provider if you have any pain or discomfort in your stomach.
  • are pregnant or plan to become pregnant. It is not known if SYLVANT will harm your unborn baby. You should not become pregnant while receiving treatment with SYLVANT. Females who are able to become pregnant should use effective birth control during treatment with SYLVANT and for 3 months after stopping treatment.
  • are breastfeeding or plan to breastfeed. It is not known if SYLVANT passes into your breast milk. You and your healthcare provider should decide if you will take SYLVANT or breastfeed. You should not do both.

Tell your healthcare provider about all the medicines you take,

including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Please see full Prescribing Information and Patient Information for additional Important Safety Information.

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Important Safety Information

What is SYLVANT?

SYLVANT® (siltuximab) is a prescription medicine used to treat people with multicentric Castleman’s disease (MCD) who do not have human immunodeficiency virus (HIV) and human herpesvirus-8 (HHV-8) infection. It is not known if SYLVANT is safe and effective in children.

Who should not take SYLVANT?

Do not take SYLVANT if you have had a severe allergic reaction to siltuximab or any of the ingredients in SYLVANT. See the Medication Guide for a complete list of ingredients in SYLVANT.

What are the possible side effects of SYLVANT?

SYLVANT may cause serious side effects, including:

Infections. SYLVANT may lower your ability to fight infections. Tell your healthcare provider right away if you have any signs or symptoms of an infection during treatment with SYLVANT.

Infusion and allergic reactions. If you have an infusion or allergic reaction while receiving SYLVANT, your healthcare provider will stop your infusion and treat your reaction. If you have a severe infusion or allergic reaction, your healthcare provider may stop your treatment completely. Tell your healthcare provider or get medical help right away if you have any of these symptoms during or after your infusion of SYLVANT:

  • back pain
  • chest pain or tightness
  • nausea and vomiting
  • flushing
  • redness
  • irregular heart beat (palpitations)
  • trouble breathing
  • wheezing
  • dizziness or light-headedness
  • swelling of the lips
  • skin rash
  • headache
  • itching

The most common side effects of SYLVANT include:

rash, itching, upper respiratory tract infection, swelling, weight gain, and increased blood level of uric acid.

These are not all the possible side effects of SYLVANT. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Before you take SYLVANT, tell your healthcare provider about all of your medical conditions, including if you:

  • have an infection. You should not take SYLVANT if you have a severe infection.
  • have had a recent vaccination or are scheduled to receive any vaccinations. You should not receive a live vaccine during your treatment with SYLVANT.
  • have or have had any stomach or bowel (intestine) problems, such as diverticulitis or ulcers. Tell your healthcare provider if you have any pain or discomfort in your stomach.
  • are pregnant or plan to become pregnant. It is not known if SYLVANT will harm your unborn baby. You should not become pregnant while receiving treatment with SYLVANT. Females who are able to become pregnant should use effective birth control during treatment with SYLVANT and for 3 months after stopping treatment.
  • are breastfeeding or plan to breastfeed. It is not known if SYLVANT passes into your breast milk. You and your healthcare provider should decide if you will take SYLVANT or breastfeed. You should not do both.

Tell your healthcare provider about all the medicines you take,

including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Please see full Prescribing Information and Patient Information for additional Important Safety Information.

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Biopsy

The removal and examination of tissue, cells, or fluids from the body.

Cytokines

Powerful molecules that are normally secreted by the cells of the immune system in response to infectious or noninfectious agents.

Cytokine storm

An overreaction of the body’s immune system in which too many cytokines are released into the bloodstream very quickly, with potentially severe or life-threatening effects.

Idiopathic

The underlying cause or origin of a disease is unknown.

Lymph nodes

Lymph nodes make immune cells that help the body fight infection.

Interleukin-6 (IL-6)

A key signaling molecule that helps to regulate the body’s immune system.

Pathologist

A doctor who evaluates the changes caused by disease in tissues and body fluids and helps reach a diagnosis.

Intravenous (IV) infusion

Administration of a drug solution into a vein.

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