PI

View information for CIDP or Chronic ITP

What is Privigen?

Privigen is an intravenous immunoglobulin (IVIg) therapy that contains antibodies—proteins that are part of your immune system. The primary antibody found in Privigen, immunoglobulin G, is the main type of antibody made by your immune system.

Your doctor may refer to your Privigen treatment as "Ig," "intravenous Ig," or "IVIg."

What is primary immunodeficiency (PI)?

People with PI have immune systems that do not work as well as they should. There are at least 550 different kinds of PIs, but these rare conditions all have something in common. In all PIs, a part of the body’s immune system, like antibodies, is missing or does not function correctly. Because of this, infections may be frequent, severe, long-lasting, or hard to treat, even with antibiotics.

According to the Jeffrey Modell Foundation, the following are common symptoms of PI. If you or a loved one has 2 or more of them, you should speak to a healthcare professional to see if PI may be the cause.

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10 Warning Signs of PI for Adults*

  1. Two or more new ear infections within 1 year.
  2. Two or more new sinus infections within 1 year, in the absence of allergy.
  3. One pneumonia per year for more than 1 year.
  4. Chronic diarrhea with weight loss.
  5. Recurrent viral infections (colds, herpes, warts, condyloma).
  6. Recurrent need for intravenous antibiotics to clear infections.
  7. Recurrent, deep abscesses of the skin or internal organs.
  8. Persistent thrush or fungal infection on skin or elsewhere.
  9. Infection with normally harmless tuberculosis-like bacteria.
  10. A family history of PI.

10 Warning Signs of PI for Children*

  1. Four or more new ear infections within one year.
  2. Two or more serious sinus infections within one year.
  3. Two or more months on antibiotics with little effect.
  4. Two or more pneumonias within one year.
  5. Failure of an infant to gain weight or grow normally.
  6. Recurrent, deep skin or organ abscesses.
  7. Persistent thrush in mouth or fungal infection on skin.
  8. Need for intravenous antibiotics to clear infections.
  9. Two or more deep-seated infections including septicemia.
  10. A family history of PI.

*These warning signs were developed by the Jeffrey Modell Foundation Medical Advisory Board. Consultation with Primary Immunodeficiency experts is strongly suggested. ©2026 Jeffrey Modell Foundation.

How does Privigen work in PI?

Privigen replaces the IgG that patients with certain types of PI are missing or isn't working properly to help strengthen the immune system and prevent serious and recurring infections. The exact way that Privigen works is not completely understood.

Privigen is proven safe & effective

Study Results

Receiving Privigen therapy

Infusion Process
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Make the most of your Privigen therapy

Get information to help you talk to your doctor about Privigen, an IVIg therapy for PI.

Download the PI Patient Education Brochure
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