Glossary of terms

Anemia: A condition in which the body has below-normal levels of red blood cells.

Autoimmune condition: A condition in which the body’s immune system accidentally attacks itself.

CT scan: Computed tomography (CT) is a method of producing an image of the internal structures by passing an x‑ray through the body.

Excisional biopsy: During this surgical procedure, an incision/cut is made in the skin to remove a swollen lymph node, which is then examined under a microscope to look for signs of a disease. A small amount of healthy tissue around the abnormal area may also be removed.

Fine needle aspiration (FNA) or core biopsy: Procedures during which tissue is obtained from a swollen lymph node with the help of a fine needle and syringe.

Hematologist-oncologist: A doctor who specializes in the branch of medical science that deals with cancers of the blood and blood-forming tissues.

Hemoglobin: A protein inside red blood cells that carries oxygen from the lungs to the rest of the body and brings carbon dioxide back to the lungs.

HHV-8: Human herpesvirus-8.

HIV: Human immunodeficiency virus.

Idiopathic: Idiopathic means that the underlying cause or origin of a disease is unknown.

Idiopathic multicentric Castleman disease (iMCD): A rare condition that affects multiple groups of lymph nodes throughout the body. Patients with iMCD are HIV negative and HHV-8 negative.

Incisional biopsy: It is a procedure in which a sample of abnormal tissue or lump is removed by making a cut through the skin. The tissue sample is then examined under the microscope for any signs of a disease.

Infectious disease expert: A doctor who specializes in infectious disease medicine, a subspecialty of internal medicine that focuses on diagnosing and managing infections.

Interleukin-6 (IL-6): A key signaling molecule that helps to regulate the body’s immune system.

Intravenous (IV) infusion: Administration of the drug solution into a vein.

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

Nephrologist: A doctor who specializes in the diagnosis and treatment of kidney abnormalities.

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

PET scan: Positron emission tomography (PET) is a method of producing a 3-dimensional image of the internal structures of body tissues after administering a natural biochemical substance like glucose or fatty acids. These images are generated with the help of a computer.

Rheumatologist: A doctor who specializes in the branch of medicine that deals with rheumatic conditions.

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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.

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 Patient Information 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 for additional Important Safety Information.