News Release

What is Ultrafiltration (UF)?

• Ultrafiltration is the process of removing fluids from a kidney dialysis patient's bloodstream during peritoneal dialysis (PD), which is one form of dialysis that is usually performed in the home.
• Dialysis helps eliminate waste and fluids from the bloodstream when the kidneys can no longer fulfill their role of filtering and removing wastes, toxins and fluid from the body.
• In PD, extra fluids and waste are removed from the blood inside the body, using the body's own peritoneal membrane, or abdominal lining, as a natural filter.
• Dialysis fluid enters the peritoneal cavity through a flexible catheter, which is surgically inserted in the abdomen. Extra fluid and waste travel from the blood (high concentration of waste, etc.) across the peritoneal membrane into the dialysis fluid. The dialysis fluid is drained from the abdomen through the catheter after a pre-determined time when the dialysis fluid has absorbed as much waste as it can.
• In hemodialysis or peritoneal dialysis, excess fluid is removed by ultrafiltration.
• Net ultrafiltration measures dialysis efficacy, which is equal to the difference between the volume of dialysis solution used at the beginning of the dialysis treatment and the volume drained at the end.
• Negative net ultrafiltration occurs when some of the infused dialysis solution is reabsorbed into the bloodstream, resulting in a lower volume of fluid drained at the end of the dialysis session. As a result, more fluid remains in the patient's body rather than being eliminated, and less waste is removed.
• Patients with ultrafiltration failure absorb glucose more rapidly from the peritoneal cavity, dissipating the osmotic gradient.

Why is Ultrafiltration Important?

• Effective fluid management is a primary goal for end-stage kidney disease patients on PD therapy, since the patient's own kidneys have limited, if any, ability to eliminate excess fluid from the bloodstream.
• Effective fluid management improves the ability to control weight gain and edema-the abnormal accumulation of fluid in the tissue spaces, cavities or joint capsules of the body.
• Hypertension is a common manifestation of too much fluid in the body, contributing to worsened cardiovascular disease in renal patients.
• Achieving proper fluid balance can optimize a patient's quality of life and decrease morbidity.

How Do Dialysis Solutions Achieve Ultrafiltration?
Prior to EXTRANEAL, dialysis solutions available in the United States used glucose as the osmotic agent, which acts as the driving force in the removal of fluids. Dialysis relies on osmosis, a natural process where substances move across a semi-permeable membrane until concentrations are the same on both sides of the membrane. There is a need for efficient dialysis solutions that optimize fluid and waste removal with minimal metabolic side effects. Dextrose solutions may worsen changes in blood lipids that are associated with renal failure. The goal is to maximize ultrafiltration while minimizing the amount of glucose absorbed.

EXTRANEAL, manufactured by Baxter Healthcare Corporation, is a PD solution that contains 7.5% icodextrin-the primary osmotic agent. EXTRANEAL solution uses a novel osmotic agent, which is a polymer of glucose, to remove greater amounts of fluid over the long dwell period (8- to 16-hours) as compared to standard 1.5% and 2.5% dextrose solutions. EXTRANEAL maintains the osmotic gradient independently of membrane characteristics, restoring fluid balance in patients with ultrafiltration failure.

EXTRANEAL is indicated for a single daily exchange for the long dwell during continuous ambulatory peritoneal dialysis or automated peritoneal dialysis for the management of chronic renal failure. In clinical trials, EXTRANEAL has been shown to result in greater net ultrafiltration compared with 1.5% and 2.5% dextrose solutions, and to result in higher creatinine and urea nitrogen clearances compared with 2.5% dextrose solution.

EXTRANEAL solution is contraindicated in patients with a known allergy to cornstarch or icodextrin or in patients with glycogen storage disease. In clinical trials the most frequently reported adverse events occurring in >10% of patients, and more common in EXTRANEAL patients than in control patients, were peritonitis, upper respiratory infection, hypertension and rash. These were also observed in control patients. The most common treatment-related adverse event for EXTRANEAL patients was skin rash. Since falsely elevated glucose levels have been observed with blood glucose monitoring devices and test strips that use glucose dehydrogenase pyrroloquinolinequinone (GDH-PQQ)-based methods, these should not be used to measure glucose levels in patients administered EXTRANEAL. Patients with insulin-dependent diabetes may require modification of insulin dosage following initiation of treatment. For more information on EXTRANEAL, including prescribing information, see www.baxter.com/extraneal.

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

How Can I Get More Information About Kidney Disease?
For more information about kidney disease, please visit www.kidneydirections.com.

(Baxter and EXTRANEAL are trademarks of Baxter International Inc. and its affiliates.)