Novel Technology That Reduces Infectious Prions `Mad Cow Disease' from Blood Unveiled at International Transfusion Meeting

Business Wire, July 13, 2004

EAST HILLS, N.Y. -- Pall Provides Prion Research Update in Preparation for European Availability

Pall Corporation (NYSE: PLL) unveiled an innovative, proprietary technology that reduces prions from blood prior to a transfusion at the annual meeting of the International Society for Blood Transfusion (ISBT) in Edinburgh, Scotland today. The soon to be released Leukotrap(R) Affinity Prion Reduction Filter will provide the dual benefit of reducing harmful white blood cells while also reducing infectious prions, the rogue proteins that cause variant Creutzfeldt-Jakob Disease (vCJD). The Company presented the latest animal model research results in anticipation of launching the new filter in Europe in early 2005, where the problem of vCJD, the human form of bovine spongiform encephalopathy (BSE) or mad cow disease, is most critical.

The Pall prion reduction technology will provide a multi-targeted approach to blood safety by reducing leukocytes and infectious prions that are either cell associated or non-cell associated. In blood, about 60 percent of prion infectivity resides in leukocytes (cell-associated) and about 40 percent in plasma (non-cell associated). Research results show that the new filter has an affinity to all types of prions, including aggregated, denatured and normal.

"This is a major milestone in the quest to protect the public from this insidious and always fatal neurodegenerative disease," said Eric Krasnoff, Chairman and CEO of Pall Corporation. "We are moving this technology forward rapidly. This is a seminal event in the international effort to stop the spread of vCJD. Blood centers and hospitals will soon be able to combine both prion and leukocyte reduction in a single, simple step."

The specter of prion transmission from human-to-human via a blood transfusion came to the forefront in December 2003 when a case of vCJD was identified in a person who received a blood transfusion six years earlier from a donor who later died of the disease. Since vCJD has an unknown, albeit lengthy, incubation period that is asymptomatic, there is no way to know how many people already have the disease and how many could have already transmitted it via blood transfusion.

Prion Removal Research Results

With support from the New York Institute of Basic Research, Pall Corporation is studying the new filter using three different assays -- Western blot assay, bioassay and animal models of prion disease -- to validate reduction of infectious prions.

An endogenous infectivity study evaluated the efficacy of a prototype filter for the removal of scrapie-infected prions from red blood cell concentrates. After a 300-day incubation period, none of the hamsters (20) that received the filtered red cells developed scrapie, a transmissible spongiform encephalopathy. During the same period, two out of the 18 hamsters that received unfiltered red cells developed scrapie, exhibiting the clinical signs and symptoms of the disease.

It was found that the prototype Pall prion removal filter removed infectious prions from red cell concentrates below the limit of detection of the Western blot assay, the gold standard used to determine the presence of prions. A bioassay was also used to quantify the amount of prion removal. It was found that the filter removed approximately 4 logs of scrapie-infected prions. The evidence to date, as demonstrated in the animal model, suggests the reduction of prions, both free and leukocyte bound, may provide a higher margin of transfusion safety.

Mr. Graham Rowe, head of Laboratory Services of the Welsh Blood Service, also reported at ISBT the results of a study he conducted to determine what, if any, effects the new filter may have on red blood cells following the usual storage periods and procedures. This study evaluated the filter using three commonly used but different anticoagulants and their associated storage times. He compared the effects of prion and leukocyte filtered red cells to leukocyte only filtered red cells, and also compared these results to historical data. These preliminary results have demonstrated that blood filtered with the Pall Leukotrap Affinity prion reduction filter is substantially equivalent to control blood units from a safety and efficacy point of view.

Since a majority of blood transfused in the industrialized world is currently leukocyte reduced, a filtration approach can swiftly and easily fit into routine operating (cGMP) practice already in use in blood centers around the world.

It is expected that the new technology will meet the requirements of the Council of Europe for a CE mark and will be ready for operational trial in Europe beginning in early 2005. The Company continues to study the new technology and will release additional results on the animal model research in the coming months. The Company is also planning to conduct clinical surveillance studies after receiving the CE mark to continue to advance knowledge about transmission of prion diseases.

A Boon to Public Health and Safety