For patients with the most frequent type of primary immunodeficiency diseases (PIDD) characterized by antibody production defects, treatment with immunoglobulin (IgG) replacement therapy is the mainstay of treatment. Since 1982, intravenous immunoglobulin (IGIV) therapy has been the standard treatment in the United States. However, interest in subcutaneous immunoglobulin (IGSC) therapy has increased over the past 5 to 10 years based largely on the extensive use of this approach in Scandinavia and the development of new IGSC products in the US that led to FDA approval of IGSC for the treatment of PIDD in 2006.

At the center of management of PIDD with IgG therapy are two main issues. The first is helping patients choose the appropriate IgG delivery modality best suited for them based on the benefits and limitations of each type of treatment. The second involves a new paradigm that has emerged that emphasizes individualizing therapy for each patient to prevent infection versus achieving a standard IgG dose or trough level for all patients.

The articles in this supplement examine both these issues as part of an overall discussion of the latest research on IgG therapy for PIDD. The articles are based on presentations given by leading immunologists on these issues at a CME symposia series that was offered in five major US cities in 2011. This supplement is supported by an educational grant from Baxter, which also supported the symposia series.

We hope that ultimately the issues discussed in this supplement will offer physicians not only expert perspective but practical clinical guidance on strategies to individualize IgG therapy for their patients with PIDD.

Ralph Shapiro, MD

Midwest Immunology Center

Plymouth, Minnesota