In a Pharmacy Times Continuing Education Supplement, Elena E. Perez, MD, PhD, examined the evolution of immunoglobulin [Ig] in its treatment use, including patient populations and potential adverse events.

Immunoglobulins are antibodies produced by differentiated B cells called plasma cells. The Ig molecule has a distinctive structure that has the ability to recognize specific antigenic determinants, and Ig formulations are produced from the pooled human plasma of donors, Perez said. This diversity allows for such formulations to have a large antibody repertoire.

Although Ig has been available since the 1950s for replacement therapy in primary immune deficiency, such as agammaglobulinemia, many other effective uses of this class of biologics have been investigated and evolved over recent decades. It is also currently used in both subcutaneous and intravenous administration to a variety of disease states, including secondary immunodeficiency ,such as chronic lymphocytic leukemia and autoimmune diseases such as Guillain-Barré Syndrome, among others. 

Additionally, Ig is often tried in refractory cases that might benefit from its anti-inflammatory effects or empirically in off-label situations. Due to its anti-inflammatory effects, high-dose Ig has been used for numerous off-label indications, including for patients with recurrent bacterial infections and reduced Ig levels in patients who also fail to respond to a protein or polysaccharide vaccine challenge. These indications have been used with varying levels of efficacy and evidence to support its use, according to Perez.

As research into the genetic basis of disease advances, the authors note that clinicians should better assess complex data surrounding safe and effective uses of Ig to treat patients who present with B-cell and T-cell deficiencies, along with those harboring gene deletions or genetic anomalies who may potentially benefit from Ig therapy.

Appropriate use of Ig can reduce disease morbidity and even save lives. However, because there is a limited supply of Ig and a need for further research into optimal use, it is important for health care professionals to better understand current and developing indications and data/levels of evidence to support Ig therapy as its role continues to evolve.

To read the full Continuing Education article, visit the Pharmacy Times website.