ZLB Bioplasma Says West Nile Virus Not a Threat to IVIG Safety; Company Joins U.S. FDA in Finding Current Processing Methods Effectively Eliminate Virus from Donated Plasma.

Business Editors & Health/Medical Writers

GLENDALE, Calif.--(BUSINESS WIRE)--Dec. 16, 2002

The West Nile Virus (WNV) is effectively eliminated during the manufacture of products derived from human plasma, according to ZLB Bioplasma Inc. in a reiteration of guidance from the U.S. Food and Drug Administration (FDA). ZLB Bioplasma is a major source of intravenous immunoglobulin -- IVIG -- and other specialty plasma-derived products for the U.S. market.

"Based on readily available data, it has been verified that procedures currently in place at ZLB Bioplasma and other IVIG manufacturers effect a more than 15-log reduction of viruses structurally similar to West Nile," said Dr. Christoph Kempf, head of virology at ZLB Bioplasma and a professor at the Department of Chemistry and Biochemistry, University of Bern, Switzerland. "In other words, in the unlikely event that West Nile or related viruses are present in unprocessed plasma, standard processing methods are capable of reducing them to undetectable levels in the finished product, thus ensuring it is safe for use."

A 15-log reduction in viral titer (concentration) means that processed plasma provides a margin of safety that is 1 billion times greater than what is generally considered to be an adequate safety margin.

Dr. Kempf's comments reiterate an October 25, 2002, guidance document published by the FDA. The document, titled "Recommendations for the Assessment of Donor Suitability and Blood and Blood Products Safety in Cases of Known or Suspected West Nile Virus Infection," states "The FDA has reviewed the viral reduction processes in place for all plasma derivatives. The methods in place have been validated to inactivate flaviviruses related to WNV ..."

WNV is an arbovirus (arthropod-borne virus) in the Flaviviridae family. It is also structurally related to bovine viral diarrhea virus (BVD) and Semliki Forest virus (SFV), which, among others, are used by the plasma fractionation industry as models for process validation studies. Together with the arboviruses, BVDV and SFV have been shown to be highly susceptible to inactivation under mildly acidic conditions (low pH). ZLB Bioplasma's IVIG manufacturing process includes treatment at pH 4.0 in the presence of trace amounts of the protease pepsin as a specific step aimed at inactivating these kinds of viruses.

Of the more than 60 arboviruses that have been isolated in North America, six cause significant illness. More recently WNV has become a concern, even though less than one percent of persons infected with WNV develop severe illness. However, its recent, rapid spread in North America, coupled with the discovery that it can be transmitted through blood transfusion and organ transplantation, has heightened public concern about the safety of products derived from human blood plasma.

"Recent statements made within this industry have inappropriately raised fears that some plasma-derived products are safer than others with respect to West Nile," said Martin Rosendale, senior vice president of sales and marketing at ZLB Bioplasma Inc. "The reality is that under current manufacturing guidelines and procedures, any threat of West Nile Virus to the safety of IVIG or other plasma-derived products, from any manufacturer, is effectively eliminated."

According to Rosendale, ZLB Bioplasma will continue to monitor WNV and other known pathogens, while also maintaining a leadership position in the future of plasma product safety.

"We recognize that the increasingly global nature of the world community means that unknown pathogens will continue to emerge as potential threats to the blood supply," Rosendale said. "ZLB is not content to rest on its 50-year history in plasma fractionation, but will continue its proactive investment in the development of new technologies for additional layers of safety against the unknown pathogen."

In more than 50 years of production, ZLB Bioplasma has experienced no documented cases of viral transmission from ZLB's ALBUMIN(a) (HUMAN) or Carimune(TM)(b) Immune Globulin Intravenous (Human) -- IVIG. In addition, ZLB Bioplasma is the only manufacturer that has been able to offer a continuous supply of IVIG since it introduced the market's first intact IVIG product in 1979, with no manufacturing interruptions due to quality control, regulatory or safety issues.

About ZLB Bioplasma Inc.

ZLB Bioplasma Inc. is a major source of intravenous immunoglobulin (human) -- IVIG -- and other specialty plasma-derived products for the U.S. The company's focus is on helping the U.S. healthcare community improve the quality of life for patients by providing a steady supply of safe and effective immune-based therapies and related services.

ZLB Bioplasma Inc.'s affiliate, ZLB Bioplasma AG, develops and manufactures the plasma-derived products, using the plasma of U.S. donors, for its U.S. Food and Drug Administration (FDA)-licensed products. ZLB Bioplasma AG, originally a laboratory of the Swiss Red Cross, has 50 years of experience in plasma fractionation. The company developed the first intact IVIG product in 1979 and is the only manufacturer to offer an uninterrupted supply since that time.

ZLB Bioplasma AG is a wholly owned subsidiary of CSL Limited, a leading biotechnology and biopharmaceutical company founded in 1916 in Melbourne, Australia.

ZLB Bioplasma's products are available nationally through wholesalers, distributors and group purchasing organizations or direct from ZLB Bioplasma. For more information, visit www.zlbusa.com or call 866/244-2ZLB (2952).

(a) For full prescribing information for ALBUMIN (HUMAN), go to

www.zlbusa.com

(b) For full prescribing information with black box warning for

Carimune(TM), go to www.zlbusa.com