Athens, Greece (July 4, 2005) -- Safety in transfusion medicine is an ongoing challenge to blood services worldwide as new threats, such as variant Creutzfeldt-Jakob Disease (vCJD), emerge. An update on the latest measures to protect the public from the human form of Bovine Spongiform Encephalopathy (BSE), commonly called Mad Cow Disease, and minimize risk of transmission through blood transfusion was presented here at the International Society of Blood Transfusion Congress. At the "Safety in Transfusion Medicine" symposium, Pall Corporation (NYSE: PLL) released new research results further validating the performance of its Leukotrap® Affinity Prion Reduction Filter System, which was CE marked with a 99.9 percent prion removal efficiency in May 2005. It is the first technology that reduces infectious prions from red cells, the most widely transfused blood component. Abnormal prions are believed to be the causative agent of vCJD.
The status of evaluations of the new filter system by blood authorities in Europe were also reported. Both the Irish Blood Transfusion Service (IBTS) and the English National Blood Service (NBS) are currently evaluating the filter system for integration into their respective practices to safeguard the blood supply from vCJD. Final results of these evaluations are expected by end 2005 or early 2006.
According to Dr. William Murphy, Medical Director of the IBTS, which just completed the first phase of its evaluation, "IBTS has completed laboratory evaluation of the filter; handling of the system is very straight forward and we are planning clinical studies in the coming months."
Dr. Roger Eglin, Head of the National Transfusion Microbiology Laboratory of the NBS, discussed the incidence and risk of vCJD transmission by blood transfusion. He reviewed the role of new technologies to reduce the risk of transfusion transmission of prions, noting that a potential impending approach is filtration.
He also discussed the status of blood donor testing to detect vCJD. Although tests are in development by several companies, no solutions are likely in the short-term. He reviewed the complexity of developing accurate and reliable tests that would meet the required criteria including sensitivity and specificity. The implementation of donor screening would be problematic without the availability of confirmatory assays to inform discussions with potentially infected donors.
Prion Reduction Confirmed
Sam Coker, Ph.D., Principal Scientist of Pall Corporation, released new research results that further support the performance of the Leukotrap Affinity Prion Reduction Filter System. The study, conducted with the Departments of Neurology, Psychiatry and Pathology of the New York University School of Medicine, tested the filter against sporadic CJD. Sporadic CJD is the most common form of prion disease that affects humans. The new research showed a 99.9 percent reduction of the prion.
"This study, a first with an actual human form of prion disease, provides additional confirmation of the performance of our technology to remove all types of prions that can adversely affect people," said Dr. Coker. The sporadic CJD study is the latest in a series of studies of the filter's capability in reducing prions, including scrapie (a prion disease affecting sheep) and mouse-adapted human vCJD. He also reviewed results of new studies that found the filter effectively reduced prions under a range of different blood processing conditions, which may vary by country and blood center.
Allan Ross, President of Pall Medical, who opened the symposium, noted that concerns about vCJD are not limited to the UK and Europe, but that the disease has manifested itself in many countries around the globe. A total of 177 people have died or been diagnosed with vCJD in Britain, Ireland, France, Canada, Italy, Portugal, the Netherlands, Japan and the U.S. This past month France identified its 13th person with vCJD and Portugal announced its first suspected human case. The UK Haemophilia Society also issued a warning to 6,000 people with hemophilia that they could have caught the disease through infected blood. In the U.S., a second cow just tested positive for BSE.
"Considering the lengthy, asymptomatic incubation period of vCJD in people, no one can accurately determine the magnitude of the next wave of an outbreak. Nor do we know how many people may be harboring the infectious prions and also donating blood," Ross explained. "Our goal is to work with blood authorities across Europe and then North America to help them integrate this new measure of safety into blood processing."
Pall developed the prion reduction technology to help blood authorities around the world stop the transmission of prions as part of the Company's mission to help safeguard the global blood supply. The adoption of the new prion reduction filter has the potential to support the global public health need for adequate supplies of safe blood. Pall is continuing its prion research and development program to apply its technologies to meet the specific requirements of each nation starting in Europe, the epicenter of vCJD, followed by North America. The Company is also developing an ante mortem test to detect infectious prions in cattle prior to entering the food supply.
Source: Eurekalert & othersLast reviewed: By John M. Grohol, Psy.D. on 21 Feb 2009
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