Cerus and Baxter Report Interim Phase III Data From the Intercept Plasma System.

Business Editors & Health/Medical Writers

SAN FRANCISCO--(BW HealthWire)--Dec. 4, 2000

Cerus Corporation (Nasdaq:CERS) and Baxter Healthcare Corporation today reported interim safety and efficacy data from the Phase IIIa clinical trial of the Intercept Plasma System, a system designed to inactivate viruses, bacteria, other pathogens and white blood cells in plasma intended for transfusion. The data, which supported the safety and efficacy of Intercept plasma, were presented at the American Society of Hematology meeting being held in San Francisco.

The data from the open-label Phase IIIa trial, which is being conducted in collaboration with the National Hemophilia Foundation's Hemophilia Research Society, were presented by Pedro deAlarcon, M.D., professor of Pediatrics, University of Virginia Medical Center. The trial has been fully enrolled with 34 patients with a variety of congenital blood clotting factor deficiencies, diseases characterized by a susceptibility to hemorrhage or increased clotting and a potential need for therapeutic or prophylactic plasma transfusions to prevent or stop bleeding. Interim data presented on the first nine patients in the trial showed that infusions of plasma treated with the Intercept Plasma System were well-tolerated. The performance of Intercept plasma was comparable to historical data on untreated plasma in terms of the measured increases in blood clotting factor levels for each patient. In addition, in cases of surgery or other invasive procedures, Intercept plasma was successful in stopping bleeding and was comparable to historical data on plasma for which pathogen inactivation was not performed.

"This is the first report of pivotal trial data for the Intercept Plasma System in the United States," said Stephen T. Isaacs, president and chief executive officer of Cerus. "The data supported the safety and efficacy of using Intercept plasma in this patient population. We look forward to reporting additional Phase III clinical data on the system, which we believe will support applications for U.S. and European approvals."

In a separate presentation, data were reported from a preclinical study on the effectiveness of the Intercept Plasma System to specifically inactivate hepatitis B (HBV) and hepatitis C (HCV) viruses in plasma. In the study, plasma was inoculated with high loads of infectious HBV and HCV. The inoculated plasma was then treated with the Intercept Plasma System and transfused into animals. The results showed that the Intercept Plasma System is capable of inactivating high levels of infectious HBV and HCV in plasma. In addition, none of the animals transfused with Intercept plasma showed serological, molecular, biochemical or histological evidence of hepatitis during a six month post-transfusion follow-up.

"These data support the potential of the Intercept Plasma System to prevent transmission of hepatitis B and hepatitis C that may occur through plasma transfusion," said Larry Corash, M.D., vice president of Medical Affairs at Cerus. "These in vivo results further reinforce existing data demonstrating the system's ability to inactivate a broad array of viruses, bacteria and other pathogens."

About Cerus

Cerus Corporation is developing medical systems and therapeutics based on the company's proprietary Helinx technology for targeting DNA and RNA to control biological replication. The company's most advanced programs are focused on systems to enhance the safety of the world's blood supply. These Intercept Blood Systems, based on the Helinx technology, are designed to inactivate viruses, bacteria and other pathogens. The Concord, Calif.-based biopharmaceutical company, in collaboration with its development and commercialization partner Baxter Healthcare Corporation, has completed a European Phase III clinical trial of the Intercept Platelet System and is conducting further clinical trials of the Intercept Blood Systems in the United States: a Phase III trial for platelets, a Phase III trial for plasma and a Phase Ic trial for red blood cells.

About Baxter

Baxter Healthcare Corporation is the principal domestic operating subsidiary of Baxter International (NYSE:BAX). Baxter International, through its subsidiaries, is a global medical products and services company that provides critical therapies for people with life-threatening conditions. The company's products and services in bioscience (biopharmaceuticals and blood collection, separation and storage devices), medication delivery and renal therapy are used by health-care providers and their patients more than 100 countries.

Statements in this news release regarding product development, clinical development, regulatory activity and product potential are forward-looking statements that involve risks and uncertainties. Actual results could differ materially from the above forward-looking statements as a result of certain factors, including the uncertainty of the timing and results of any clinical trials, action by regulatory authorities, the uncertainty of market acceptance of any products, competitive conditions, the uncertainty of future financing and other factors discussed in the companies' 1999 Annual Report on Form 10-K and Cerus' Prospectus dated Nov. 1, 2000.

Note to Editors: Helinx is a trademark of Cerus Corporation

Intercept Blood System, Intercept Platelet System, Intercept Plasma System and Intercept Red Blood Cell System are trademarks of Baxter International, Inc.