Data Presented at AAAAI Reinforce Baxter's Commitment to Making GAMMAGARD LIQUID Therapy More Convenient.

DEERFIELD, Ill. -- Baxter International Inc. (NYSE: BAX) announced data supporting further progress in efforts to make antibody therapy more convenient for patients with primary immunodeficiency (PID), including ways to give patients more options of where, how often and when they receive treatment. The data were presented in three posters at the 2009 American Academy of Allergy, Asthma & Immunology (AAAAI) Annual Meeting in Washington, D.C., on Saturday, March 14.

Current intravenous (IV) administration of immune globulins requires a healthcare professional to monitor infusions, taking up three to four hours, and current subcutaneous administration may require multiple injections and higher doses of immune globulins than IV. Data presented at AAAAI add to a growing body of evidence supporting Baxter's work to develop a different delivery method of antibody replacement therapy applied under the skin using an enzyme that can help deliver and disperse the antibodies into the body at the appropriate dose. This is an investigational study that Baxter has undertaken to develop a subcutaneous mode of administration of Intravenous Immune Globulin (IVIG) therapy to patients.

"Baxter is focused on making immune globulin therapy easier for patients with PID," said Hartmut J. Ehrlich, MD, vice president of global research and development for Baxter's BioScience business. "Data presented at AAAAI demonstrate Baxter's progress in developing a new way to deliver antibody therapy that may be more convenient for patients."

PID is a hereditary disorder marked by low to no antibodies, also known as immune globulins, which help the body fight disease and infection. People living with PID can take antibody replacement therapy to equip their immune system and avoid infections. Baxter's immune globulin therapy, GAMMAGARD LIQUID (KIOVIG in Europe), is approved for intravenous administration in the United States and Europe.

Antibody replacement therapy has been used for more than two decades to treat PID. This therapy may be delivered intravenously every three to four weeks, called IVIG, or under the skin once a week, commonly called Subcutaneous Immune Globulin (SCIG). IV therapy allows for the delivery of adequate levels of immune globulin concentrations, but require infusions under the care of a healthcare professional, spanning three or four hours. Current SCIG therapy may be administered at home once a week, but may also present challenges, such as multiple injections and a higher dose of immune globulins required to get the same therapeutic effect.

Treatment with Immune Globulin (IG) in Primary Immune Deficiency Patients: Dose Comparison Based on the Route of Administration

Data from this retrospective analysis of real-world use in the United States show current SCIG administration uses significantly more immune globulin than IVIG. The analysis from PID patients from 12,483 claims (1,382 patients) of intravenously administered immune globulins from GAMMAGARD LIQUID and 2,365 claims (258 patients) of immune globulins from a U.S.-approved subcutaneous therapy show the median dose typically given subcutaneously for patients with PID is approximately 1.39 times the median dose given intravenously.

IGIV-10% Infused Intravenously And Subcutaneously To Subjects With Primary Immunodeficiency Diseases - Comparison Of Pharmacokinetic Properties

Data from 15 patients in a prospective, multi-center study investigating tolerability, pharmacokinetics and bioavailability of subcutaneous administration of GAMMAGARD LIQUID, confirmed that compared to intravenous administration, significantly more immune globulin (137 percent) is administered subcutaneously in order to achieve similar bioavailability (amount of therapy in the blood).

30-Day Pharmacokinetic Evaluation of IV versus Subcutaneous Administration of Immunoglobulin with and without Recombinant Human Hyaluronidase 

The pre-clinical study compared the bioavailability of intravenous delivery of immune globulins (10 percent concentration) versus subcutaneous delivery of a lower volume, investigational 20 percent immune globulin therapy with and without recombinant human hyaluronidase (a treatment-modifying enzyme). The bioavailability of antibodies in the 20 percent immune globulin therapy delivered with recombinant human hyaluronidase was comparable with immune globulin 10 percent delivered intravenously. Furthermore, comparison of subcutaneously administered 20 percent immune globulin, with and without recombinant human hyaluronidase, showed improved bioavailability with the addition of recombinant human hyaluronidase. The preclinical data support furthering Baxter's Phase III development program evaluating recombinant human hyaluronidase to deliver immune globulins.

Subcutaneous Administration and Recombinant Human Hyaluronidase

Baxter is researching investigational 10 percent immune globulin therapy, which is GAMMAGARD LIQUID administered with recombinant human hyaluronidase. The combination of these two therapies could potentially make administration more convenient for PID patients with less infusion time, potentially enabling delivery of up to a monthly dose of immune globulin, administered under the skin in a single site. Investigational 10 percent immune globulin therapy with recombinant human hyaluronidase is currently being evaluated in a prospective, open-label, non-controlled Phase III clinical study being conducted in 10-20 centers in the U.S. and Canada.

Podcast: Antibody Therapy with Recombinant Human Hyaluronidase

For more information about Baxter's studies of immune globulin therapy with recombinant human hyaluronidase for patients with PID, listen to Baxter's podcast by visiting www.baxter.com.

About Primary Immunodeficiency Disorders

Primary immunodeficiency disorders encompass more than 100 diseases caused by an immune system that does not function correctly. According to the Jeffrey Modell Foundation, primary immunodeficiency affects as many as one million Americans and 10 million worldwide. For people with primary immunodeficiency, the primary cause is a lack of antibodies. IVIG therapy can help restore immune globulin levels to near normal, helping the immune system function properly and prevent infections or fight them when they occur.

About GAMMAGARD LIQUID[TM] 10%

GAMMAGARD LIQUID 10% (known as KIOVIG[TM] in Europe) is indicated for the treatment of primary immunodeficiency disorders associated with defects in humoral immunity. These include but are not limited to congenital X-linked agammaglobulinemia, common variable immunodeficiency, Wiskott-Aldrich syndrome and severe combined immunodeficiencies.

Important Safety Information

GAMMAGARD LIQUID

GAMMAGARD LIQUID is contraindicated in patients with known anaphylactic or severe hypersensitivity responses to Immune Globulin (Human). Patients with severe selective IgA deficiency (IgA < 0.05 g/L) may develop anti-IgA antibodies that can result in a severe anaphylactic reaction.

Immune Globulin Intravenous (Human) products have been reported to be associated with renal dysfunction, acute renal failure, osmotic nephrosis and death. Patients predisposed to acute renal failure include patients with any degree of pre-existing renal insufficiency, diabetes mellitus, age greater than 65, volume depletion, sepsis, paraproteinemia, or patients receiving known nephrotoxic drugs. Especially in such patients, IGIV products should be administered at the minimum concentration available and the minimum rate of infusion practicable. While these reports of renal dysfunction and acute renal failure have been associated with the use of many of the licensed IGIV products, those containing sucrose as a stabilizer accounted for a disproportionate share of the total number.

Glycine, an amino acid, is used as a stabilizer. GAMMAGARD LIQUID does not contain sucrose.

GAMMAGARD LIQUID is made from human plasma. It may carry a risk of transmitting infectious agents, e.g. viruses, and theoretically, the Creutzfeldt-Jakob disease (CJD) agent.

Components used in the packaging of this product are latex-free.

Thrombotic events have been reported in association with IGIV. Patients at risk may include those with a history of atherosclerosis, multiple cardiovascular risk factors, advanced age, impaired cardiac output, and/or known or suspected hyperviscosity, hypercoagulable disorders, and prolonged periods of immobilization.

IGIV products can contain blood group antibodies that may cause a positive direct antiglobulin reaction and, rarely, hemolysis.

Aseptic meningitis syndrome (AMS) has been reported to occur infrequently in association with IGIV treatment. Discontinuation of IGIV treatment has resulted in remission of AMS within several days without sequelae.

Various mild and moderate reactions, such as headache, fever, fatigue, chills, flushing, dizziness, urticaria, wheezing or chest tightness, nausea, vomiting, rigors, back pain, chest pain, muscle cramps, and changes in blood pressure may occur with infusions of Immune Globulin Intravenous (Human).

For full prescribing information, please visit http://www.gammagardliquid.com.

About Baxter International Inc.

Baxter International Inc. (NYSE: BAX), through its subsidiaries, develops, manufactures and markets products that save and sustain the lives of people with hemophilia, immune disorders, infectious diseases, kidney disease, trauma, and other chronic and acute medical conditions. As a global, diversified healthcare company, Baxter applies a unique combination of expertise in medical devices, pharmaceuticals and biotechnology to create products that advance patient care worldwide.

This release includes forward-looking statements concerning the company's Phase III trial of subcutaneous administration of GAMMAGARD LIQUID with recombinant human hyaluronidase and expectations regarding the results related thereto. 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: timely submission and approval of anticipated regulatory filings; the ability of the company to enroll a sufficient number of patients in the Phase III trial; the ability of the company to complete the Phase III trial successfully and on a timely basis; and other risks discussed in the company's filings with the Securities and Exchange Commission (SEC), all of which are available on the company's website. The company does not undertake any obligation to update any forward-looking statements.