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Supportive Care

Brand names:


Often used for:

Treatment of cytokine release syndrome (CRS)

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About Siltuximab

Siltuximab is used to treat severe cytokine release syndrome (CRS) during CAR T-cell immunotherapy. This drug blocks a protein called interleukin-6 (IL-6) and acts to decrease the body’s immune response (immunosuppressant) and lower cytokine production.

Patients will have regular blood draws to check blood counts and monitor kidney and liver function. Blood pressure, heart rate, breathing, and temperature may be monitored to watch for infusion-related side effects.

This drug may increase the risk of infection, especially in patients with a weak immune system.

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May be given as a liquid into a vein by IV

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Possible Side Effects

  • Swelling, edema
  • Weight gain
  • Symptoms of a common cold (runny nose, sneezing, nose and throat irritation)
  • Rash
  • Itching
  • Increased risk of infection
  • Headache
  • Constipation
  • Joint pain
  • Mouth or throat pain
  • Dry skin
  • Low blood counts (may cause increased risk of infection, bleeding, anemia and/or fatigue)
  • Liver problems
  • Increased blood cholesterol or triglyceride levels
  • Tears in the stomach or intestines
  • Infusion-related reactions: Symptoms may include chills, shortness of breath, coughing, dizziness, low blood pressure, pain in the chest, swelling of the face or neck

Not all patients who take siltuximab will experience these side effects. Common side effects are bolded, but there may be others. Please report all suspected side effects to your doctor or pharmacist.

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Tips for Families

Be sure to discuss these and other recommendations with your doctor or pharmacist.

  • Make sure all vaccinations are up to date before starting treatment. Patients should not get certain types of vaccines (known as “live” vaccines) for 3 months after receiving siltuximab.
  • Sexually active patients should take steps to prevent pregnancy while taking this drug and for 3 months after the last dose.
  • Siltuximab may make birth control pills and other hormone-based birth control methods less effective. Sexually active patients should also use another form of birth control, like condoms, to prevent pregnancy.
  • Patients should tell their doctor if they are pregnant or breastfeeding.

Also see: Tisagenlecleucel