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Baxter Announces Preliminary Phase I/II Data for Seasonal Influenza Vaccine Candidate

Key safety, immunogenicity data presented at Options for the Control of Influenza VI Conference in Toronto

DEERFIELD, Ill., July 23, 2007 /PRNewswire-FirstCall/ -- Baxter International Inc. recently announced promising initial study data for its candidate, Vero cell-based seasonal influenza vaccine, now undergoing a Phase I/II clinical trial in Europe. The preliminary data indicate that the vaccine induced strong antibody responses and good tolerability in all study populations.

The findings were presented by Hartmut J. Ehrlich, M.D., vice president of Global Research and Development for Baxter's BioScience business at a June gathering of laboratory and clinical scientists and public health professionals at the Options for the Control of Influenza VI Conference in Toronto, Canada. The active, controlled, multi-center Phase I/II trial of the seasonal influenza vaccine was designed to evaluate safety and immunogenicity of the candidate vaccine in approximately 940 subjects divided between the ages of 18-49 and 50 years of age and older.

The Phase I/II study data indicate that Baxter's seasonal candidate vaccine, which was developed using a split virus process, was effective in inducing protective levels of antibodies for all three seasonal virus strains in both age levels. Split viruses are most frequently used for seasonal influenza vaccines. Baxter's investigational pandemic H5N1 influenza vaccine, currently in Phase III trials in Europe, was developed using a whole-virus process.

In the 18-49 subject population, 99.6 percent achieved protective antibody levels for virus strains H1N1 and H3N2, and 92.9 percent for strain B. In the 50 years of age and older population, 96.6 percent achieved protective levels for virus strain H1N1, 100 percent for H3N2 and 73.3 percent for strain B.

Work on this vaccine is being completed as part of a U.S. Department of Health and Human Services (DHHS) Office of Public Health and Emergency Preparedness contract awarded to DynPort Vaccine Company LLC (DVC), a Computer Sciences Corporation company, and Baxter in May 2006 to develop seasonal and pandemic influenza vaccines. Under this contract, DVC is managing the project and clinical trials. Baxter is manufacturing the vaccines and will serve as the U.S. Food and Drug Administration (FDA) license-holder.

"I am very encouraged by the preliminary results of this Phase I/II clinical trial, which suggest that this cell culture-derived vaccine may provide protection against seasonal influenza with minimal side effects," said Frank von Sonnenburg, M.D., head of the Section of International Medicine and Public Health in the Department of Infectious Diseases and Tropical Medicine at the University of Munich.

Baxter's seasonal influenza candidate vaccine is manufactured using the company's proprietary Vero cell technology. The use of Vero cell culture, rather than conventional egg-based technology, offers several advantages. Baxter's Vero cell culture process can be initiated more rapidly due to its use of a "native" virus that does not need to be modified to allow growth in eggs, thus accelerating vaccine availability. Vaccines produced using the process can be released within approximately 12 weeks, significantly earlier than with traditional egg-based systems. In addition, all influenza strains with pandemic potential tested for growth in Vero cells have produced consistent high yields, providing the flexibility to quickly respond to emerging variant pandemic virus strains.

"Combined with the recent encouraging results from our pandemic H5N1 clinical trial, these data provide further evidence suggesting the Vero cell platform can reliably deliver safe and effective influenza vaccines in pandemic or interpandemic situations," said Dr. Noel Barrett, vice president of Global Research and Development for Baxter's Vaccines Business. "This early indication of an acceptable safety profile and immunity against key seasonal influenza viral strains is critically important as we plan the Phase III clinical trial program to provide a solid measure of the vaccine's potential to protect a large number of people during the influenza season."

Phase I/II Data

Preliminary data from the Phase I/II clinical trial presented at the Toronto meeting showed the candidate vaccine's tolerability profile to be similar to currently marketed, egg-based seasonal flu vaccines. The vaccine also generated substantial levels of cross immunity against three seasonal strains. The most common side effects observed for the trial vaccine were injection site reactions, headaches and malaise.

In addition, the analysis demonstrated that the vaccine met European Committee for Medicinal Products for Human Use (CHMP) criterion for influenza vaccine licensure with all three strains, in both age groups tested. The criterion requires that adults achieve specific levels of immunity or "seroprotection" following vaccination.


    1. This project has been funded in whole or in part with Federal (United

       States Government) funds from the Office of Public Health Emergency

       Preparedness, Office of Research and Development Coordination, under

       contract number HHS0100200600013C.

    2. Pursuant to Section 507 of P.L. 104-208 and Section 508 of P.L. 105-78;

       100% of the total of this project's costs are financed with Federal

       (United States Government) money.

    3. The content of this publication does not necessarily reflect the views

       or policies of the United States Department of Health and Human

       Services, nor does mention of trade names, commercial products, or

       organizations imply endorsement by the U.S. Government.

About CSC

Computer Sciences Corporation is a leading global information technology (IT) services company. CSC's mission is to provide customers in industry and government with solutions crafted to meet their specific challenges and enable them to profit from the advanced use of technology.

With approximately 87,000 employees, CSC provides innovative solutions for customers around the world by applying leading technologies and CSC's own advanced capabilities. These include systems design and integration; IT and business process outsourcing; applications software development; Web and application hosting; and management consulting. Headquartered in El Segundo, Calif., CSC reported revenue of $14.9 billion for the 12 months ended March 30, 2007.

About Baxter

Baxter International Inc., through its subsidiaries, assists healthcare professionals and their patients with the treatment of complex medical conditions, including hemophilia, immune disorders, cancer, infectious diseases, kidney disease, trauma and other conditions. The company applies its expertise in medical devices, pharmaceuticals and biotechnology to make a meaningful difference in patients' lives.

Further information about this trial will be posted at

The safety and efficacy of this product has not been established. This product is currently under clinical investigation and has not been licensed by the FDA.

This release includes forward-looking statements concerning the company's vaccine products, including with respect to clinical trials, licensures, and the advantages of the vaccine products. The statements are based on assumptions about many important factors, including the following, which could cause actual results to differ materially from those in the forward-looking statements: satisfaction of regulatory and other requirements for timely commencement of additional clinical trials; additional clinical results demonstrating the safety and efficacy of the products; market acceptance of vaccines developed with Vero cell technology relative to egg- based or other alternatives; continued public commitment to addressing avian flu and other pandemic threats including additional experience producing such vaccines at a large scale; and other risks identified in the company's most recent filing on Form 10-Q and other SEC filings, all of which are available on the company's web site. The company does not undertake to update its forward-looking statements.

Posted: July 2007