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Video: What Is Primary Immunodeficiency?

Did you know? An estimated 6 million people worldwide live with serious immune system problems.


Every day, the human immune system fights off countless infections from viruses, bacteria and other organisms. For many people with primary immunodeficiency disease (PI), that protection isn’t always available due to a defect in one of the functions of the body’s normal immune system.

That can lead to repeated infections that are slow to respond to treatment, organ damage and the development of debilitating illnesses. Patients may face repeated rounds of antibiotics or be hospitalized for treatment. Many people living with PI have missed school, work or time with family and friends.

“It is estimated that 6 million people worldwide are living with PI and up to 90% of people with the condition are still undiagnosed,” explains Mittie Doyle, Vice President of CSL Behring’s R&D Immunology Therapeutic Area.

There are more than 400 types of PI that vary in severity, according to the U.S. Centers for Disease Control and Prevention. For some, the problem is diagnosed in infancy or childhood. But PI often goes untreated because there are no unique or specific symptoms (but there are common signs). Patient access to care and appropriate treatment help prevent serious and life-threatening complications in people with PI.

Plasma and the PI Connection

“Once correctly diagnosed and treated, people with PI can live full and active lives. Treatment for PI depends upon many factors, and one possible treatment is immunoglobulin (Ig) (sometimes called immune globulin or gamma globulin) replacement therapy,” Doyle said.

Ig replacement therapy is the administration of purified plasma, the clear liquid portion of blood that contains antibodies which fight infections. Intravenous Ig is administered by a healthcare professional. Ig can also be administered at home as an injection via mechanical infusion pump or syringe.

Ig therapy only partly replaces the antibodies that a person’s body should be making. These antibodies are metabolized by the body and must be constantly replenished. Therefore, people with PI who use Ig therapy must do so on a regular basis and usually over a lifetime.

Ig is prepared using plasma collected from people with normal immune systems and who have been carefully screened. Data show that it takes 130 plasma donations to treat one person with PI for a year.

“Producing Ig therapy requires a constant supply of donor plasma,” Doyle said. “We need more donors who can step up and help us provide the necessary treatment that those with PI rely on to lead normal lives.”