Gammagard May Target Primary Pathway Involved In Alzheimer's Disease
The University of Tennessee Health Science Center and Baxter International announced data from a laboratory study demonstrating natural antibodies contained in GAMMAGARD LIQUID [Immune Globulin Intravenous (Human)] (IGIV), marketed as KIOVIG in the European Union, a plasma-derived antibody replacement therapy indicated for primary immunodeficiency disorders and being studied in Alzheimer's disease, binds directly to multiple aggregated, or clustered, forms of the beta-amyloid peptide molecule. The beta-amyloid molecule may contribute to beta-amyloid plaques, which are thought to be the primary culprit causing Alzheimer's disease. The results of this in vitro (laboratory) study were presented by Dr. Brian O'Nuallain, assistant professor, UT Medical Center, Knoxville, University of Tennessee Health Science Center at the American Academy of Neurology (AAN) Annual Meeting.
Previous clinical studies suggest that antibody-based immunotherapy may boost the body's own immune response to reduce beta-amyloid, the protein responsible for plaque formation commonly found in the brains of Alzheimer's disease patients. In addition, recent laboratory research suggests that specific forms of beta-amyloid - oligomers and fibrils that are aggregates or clusters of beta-amyloid - may be toxic to the neurological system and lead to the progression of Alzheimer's disease.
"IGIV therapy may contain antibodies that possibly have strong binding characteristics to several aggregated forms of the beta-amyloid peptide that are believed to cause Alzheimer's disease," said Dr. O'Nuallain. "These initial findings could be promising in Alzheimer's disease research using naturally occurring antibodies."
The oral presentation at AAN, entitled "Affinity Isolation and Characterization of Abeta Conformer-Reactive Antibodies Contained in Human Immune Globulin (IVIG)," showed that GAMMAGARD contains naturally occurring antibodies that directly bind to different forms of beta-amyloid protein, including oligomers and fibrils.
"Observations from this study provide insight into how GAMMAGARD LIQUID may be of potential clinical benefit for Alzheimer's patients," said Dave Morgan, director of Neuroscience Research, University of South Florida. "This study suggests that GAMMAGARD LIQUID may target the primary pathway involved in Alzheimer's disease and justifies additional studies to evaluate whether GAMMAGARD LIQUID can effectively reverse the effects of Alzheimer's disease."
According to the Alzheimer's Association, an estimated 5.2 million Americans have Alzheimer's disease, including one out of eight people age 65 and older, and the number of new cases per year is expected to grow to 454,000 by 2010. No cure currently exists that can halt or delay the brain deterioration associated with Alzheimer's disease, but new research shows encouraging results. The study's findings showed how the mechanism of action of GAMMAGARD may work on multiple forms of the beta-amyloid peptide to protect the human brain from dementia and may facilitate the development of treatment for patients with Alzheimer's disease.
Additional GAMMAGARD Trials in Alzheimer's Disease
At the AAN meeting, other studies will be presented on the use of GAMMAGARD in Alzheimer's disease. One oral presentation scheduled for April 17 - "A Double-Blind, Placebo-Controlled, Phase II Clinical Trial of Intravenous Immunoglobulin (IVIG) for Treatment of Alzheimer's Disease" - will discuss the evaluation of the efficacy, tolerability and safety of GAMMAGARD in the treatment of mild to moderate stage Alzheimer's disease.
The oral presentation, "Intravenous Immunoglobulin Increases Brain Glucose Metabolism in Alzheimer Disease," will also be presented on April 17 and will discuss the analysis of brain activity using imaging data. The brain metabolism results were based on serial Positron Emission Tomography (PET) scans, an imaging technique sometimes used in the diagnosis of Alzheimer's disease.
Further, Baxter and The Alzheimer's Disease Cooperative Study (ADCS) group announced a decision to pursue a multi-center U.S. Phase III study evaluating the role of GAMMAGARD. The study design is undergoing review with the U.S. Food and Drug Administration with the intention of initiating patient recruitment later in 2008. The trial is expected to include approximately 35 leading academic centers in the United States that are members of ADCS.