Immunoglobulin (Ig) replacement therapy is one of the most important and successful therapies for people with primary immunodeficiency diseases (PI), especially for those who are antibody deficient. The therapy is both lifesaving and lifelong, and it plays a huge role in the lives of many people with PI.
What Are Primary Immunodeficiency Diseases?
Primary immunode ciency diseases (PI) are a group of disorders caused by basic defects in immune function of the cells and proteins of the immune system. There are more than 350 types of PI. Some are relatively common, while others are quite rare. Some affect a single cell or protein of the immune system and others may affect two or more components of the immune system. Although PI may differ from one another in many ways, they share one important feature. They all result from a defect in one or more of the elements or functions of the normal immune system.
History of Immunoglobulin Replacement Therapy
Gamma globulin derived from human plasma was first introduced as a treatment option in 1952 when gamma globulin was injected intramuscularly (IM) to treat patients with recurrent infections who had antibody immunodeficiencies. Dosing was very difficult because only small amounts of gamma globulin could be given in each painful shot. Much scientific investigation in the 1960s and 1970s finally led to a suitable gamma globulin product that could be used intravenously. People with PI have been treated with intravenous immunoglobulin replacement therapy (IVIG) for over 30 years. IVIG has greatly reduced the complications of bacterial infections in people affected by antibody deficiencies.
With the discovery of well-tolerated preparations of IVIG in the 1980s, the suboptimal, painful IM administration was no longer used. This shift to IVIG changed the face of PI treatment.