Baxter Announces the Commercial Launch of HYLENEX at ACEP for Use in Pediatric Rehydration.

Data from the First Pediatric Rehydration Study, INFUSE-PEDS 1, Published Today in Pediatrics

BOSTON -- Baxter International Inc. (NYSE: BAX) today announced the commercial launch of HYLENEX recombinant (hyaluronidase human injection) for use in pediatric rehydration at the 2009 American College of Emergency Physicians (ACEP) scientific assembly (Boston). HYLENEX, an enzyme, allows fluids to be administered under the skin (subcutaneously) rather than through a vein. This allows for rapid treatment initiation and delivery of intravenous (IV)-like fluid rates, which can help lead to successful rehydration of children in a less invasive manner. Additionally, data from Baxter's Increased Flow Utilizing Subcutaneously-Enabled (INFUSE) PEDS 1 study are debuting today in the preeminent pediatric journal, Pediatrics. The study was designed to assess the efficacy, safety and clinical utility of HYLENEX recombinant-facilitated subcutaneous rehydration in mild to moderately dehydrated children ages two months to 10 years. This approach was found to be effective, easy to use and well-tolerated.1 Baxter licensed HYLENEX, the first and only recombinant human hyaluronidase, from Halozyme Therapeutics, Inc. (Nasdaq: HALO).

The commercial launch and data publication coincide with the approaching cold/flu season, offering an alternative to IV therapy for children with dehydration, a potentially serious consequence of viral respiratory diseases including influenza and other conditions that can cause fluid loss.

"HYLENEX exemplifies Baxter's ongoing commitment to innovation and introducing products that help to improve the treatment experience and overall standard of care - in this case for parents, patients and caregivers alike," said Camille Farhat, general manager of Baxter Pharmaceuticals and Technologies, part of Baxter's Medication Delivery business. "The data published today indicate that treatment facilitated by HYLENEX was considerably preferred by parents, and highly rated by clinicians, for its ability to effectively rehydrate mild to moderately dehydrated children in a much less invasive way."

"Baxter's launch of HYLENEX for use in pediatric hydration is an important achievement for our alliance," said Jonathan Lim, M.D., president and CEO of Halozyme. "We look forward to continuing to partner with Baxter to pursue HYLENEX use in additional patient populations as the benefits of subcutaneous administration of fluids and medications are increasingly realized."

Baxter manufactures and markets HYLENEX and continues to build clinical evidence to support its use. Baxter licensed the HYLENEX technology from Halozyme, which discovered and completed development work to secure U.S. Food and Drug Administration (FDA) approval. As HYLENEX is being introduced into the pediatric rehydration market, Baxter continues to study its use in other areas.

Pediatric Rehydration Clinical Program

The safety and efficacy of HYLENEX has been demonstrated through clinical trial results in mild to moderately dehydrated children as part of the INFUSE clinical research program. New data published today from the INFUSE-PEDS 1 study (n=51) showed that subcutaneous treatment facilitated by HYLENEX successfully rehydrated 94 percent of pediatric patients. The data also showed HYLENEX was fast and simple to initiate as median time from insertion to start of subcutaneous therapy was two minutes. In addition, the therapy was easy to administer, as 90 percent of catheters were successfully inserted on the first attempt and 96 percent of clinicians rated the procedure easy to perform. HYLENEX recombinant-facilitated subcutaneous rehydration was also highly preferred by parents, as nine out of 10 surveyed were satisfied or very satisfied with the procedure and reported their experience with treatment facilitated by HYLENEX was the same or better than previous IV experience.1

"To have another option for rehydration is very important to clinicians, because our options were fairly limited previously and in the case of IV, could take 20 to 40 minutes on average to initiate. With HYLENEX, we can start infusing fluids into children in a matter of minutes," said Coburn Allen, M.D., assistant professor, Department of Pediatrics, Section of Emergency Medicine and Section of Infectious Diseases, Baylor College of Medicine, Houston. "These data, in mild to moderately dehydrated children, show HYLENEX is efficacious, that we are successfully hydrating children, and that we are able to give clinically relevant fluid volumes in the same timeframe that we typically have given them by IV."

Research continues to progress, with interim results from a follow-up study, INFUSE-PEDS 2, being presented at ACEP on October 5, 2009, at 8:00 am ET. This phase IV, multi-center, randomized controlled study compares HYLENEX recombinant-facilitated subcutaneous rehydration to IV administration of fluids for mild to moderately dehydrated children.

Please see Important Risk Information for HYLENEX at the end of the press release.

Full Prescribing Information is available at http://www.hylenex.com/pdf/prescribe.pdf.

About HYLENEX

HYLENEX, approved by the FDA for subcutaneous fluid administration, works by temporarily making the tissue beneath the skin more permeable (capable of being passed through) and able to absorb fluid, allowing fluids to be more readily absorbed into the blood vessels. HYLENEX can be given in a site that is convenient for both the child and caregiver, such as in the child's upper back, while the child is held by a parent. Once HYLENEX has been injected, fluids can be administered subcutaneously. Special care must be taken in pediatric patients to avoid over hydration by controlling the rate and total volume of the infusion.2 When solutions devoid of inorganic electrolytes are given subcutaneously, some complications may occur.2

About Dehydration and IV Fluid Administration

Dehydration often results from an illness in which fluid loss is greater than fluid intake, such as vomiting or diarrhea.

One of the most common causes of dehydration in children in the U.S. is acute gastroenteritis (or stomach flu), which is responsible for more than 1.5 million outpatient visits, 200,000 hospital stays, and approximately 300 deaths per year.3 Many pediatric emergency physicians will treat mild to moderately dehydrated children via IV therapy. Yet, a study has shown that IV treatment was considered one common source of "worst pain" for children during hospitalization.4 Re-sticks can be particularly common with children - a study at an academic children's hospital found that nearly half of pediatric patients required two or more IV sticks.5

About Baxter

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.

About Halozyme

Halozyme Therapeutics, Inc. (Nasdaq: HALO) is a biopharmaceutical company developing and commercializing products targeting the extracellular matrix for the endocrinology, oncology, dermatology and drug delivery markets. The company's portfolio of products and product candidates is based on intellectual property covering the family of human enzymes known as hyaluronidases and additional enzymes that affect the extracellular matrix. Halozyme's Enhanze([TM]) Technology is a novel drug delivery platform designed to increase the dispersion and absorption of biologics. The company has key partnerships with Roche to apply Enhanze Technology to Roche's biological therapeutics for up to 13 targets and with Baxter BioScience to apply Enhanze Technology to Baxter's biological therapeutic compound, GAMMAGARD LIQUID([TM]). The product candidates in Halozyme's research pipeline target multiple areas of significant unmet medical need. For more information visit www.halozyme.com.

This release includes forward-looking statements concerning the use of HYLENEX recombinant for pediatric rehydration, HYLENEX recombinant-facilitated subcutaneous rehydration and the companies' expectations related to HYLENEX. 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: the anticipated timing of regulatory filings and the success of certain regulatory events; the effectiveness of the products described in this release; demand for and market acceptance of the products described in this release; the impact of competitive products and pricing; internal and external factors that could impact commercialization; and other risks discussed in each company's filings with the Securities and Exchange Commission (SEC) that could cause actual results to differ materially from those in the forward-looking statements. Each company's SEC filings are available on its respective website. The companies do not undertake any obligation to update any forward-looking statements. Actual results or experience could differ materially from the expectations contained in the forward-looking statements.

Important Risk Information

* Hypersensitivity to hyaluronidase or any other ingredient in the formulation is a contraindication to the use of this product.

* Discontinue HYLENEX recombinant (hyaluronidase human injection) if sensitization occurs.

* Hyaluronidase should not be used to enhance the absorption and dispersion of dopamine and/or alpha agonist drugs.

* Hyaluronidase should not be injected into or around an infected or acutely inflamed area because of the danger of spreading a localized infection.

* Hyaluronidase should not be used to reduce the swelling of bites or stings.

* Hyaluronidase should not be used for intravenous injections because the enzyme is rapidly inactivated.

* Furosemide, the benzodiazepines and phenytoin have been found to be incompatible with hyaluronidase.

* The most frequently reported adverse experiences have been local injection site reactions.

* Hyaluronidase has been reported to enhance the adverse events associated with co-administered drug products.

* Anaphylactic-like reactions following retrobulbar block or intravenous injections have occurred, rarely.

* Edema has been reported most frequently in association with subcutaneous fluid administration.

* The rate and volume of subcutaneous fluid administration should not exceed those employed for intravenous infusion. As with all parenteral fluid therapy, use the same precautions for restoring fluid and electrolyte balance.

* Special care must be taken in pediatric patients to avoid over hydration by controlling the rate and total volume of the infusion.

* When solutions devoid of inorganic electrolytes are given subcutaneously, hypovolemia may occur.

Baxter and Hylenex are trademarks of Baxter International Inc.

1Baxter Data on File.

2HYLENEX Full Prescribing Information.

3 King C, Glass R, Bresee J, et al. Managing Acute Gastroenteritis Among Children. Atlanta, GA: Department of Health and Human Services, Centers for Disease Control and Prevention; 2003. Nov. 21.

4 Cummings EA, Reid, GJ, et al. Prevalence and Source of Pain in Pediatric Inpatients. Pain. 1996; 68; 25-31.

5 Spandorfer PR, Evaline A., Joffe MD, et al. Oral Versus Intravenous Rehydration of Moderately Dehydrated Children: A Randomized, Controlled Trial. Pediatrics. 2005; 115; 295-301.