Hypervolemia may occur if the dosage and rate of infusion are too high [see Warnings and Precautions (5.2)].

FLEXBUMIN 5% is a sterile, nonpyrogenic preparation of albumin in single dosage form for intravenous administration. Each 100 mL contains 5 g of albumin. It has been adjusted to physiological pH with sodium bicarbonate and/or sodium hydroxide and stabilized with N-acetyltryptophan (0.004M) and sodium caprylate (0.004M). The sodium content is 145 ± 15 mEq/L. FLEXBUMIN 5% contains no preservative and none of the coagulation factors found in fresh whole blood or plasma. FLEXBUMIN 5% is a transparent or slightly opalescent solution which may have a greenish tint or may vary from a pale straw to an amber color and is clear of particulate matter.

FLEXBUMIN 5% is manufactured from human plasma by the modified Cohn-Oncley cold ethanol fractionation process, which includes a series of cold-ethanol precipitation, centrifugation and/or filtration steps followed by pasteurization of the final product at 60 ± 0.5°C for 10 to 11 hours. This process accomplishes both purification of albumin and reduction of viruses.

In vitro studies demonstrate that the manufacturing process for FLEXBUMIN 5% provides for effective viral reduction. These viral reduction studies, summarized in Table 2, demonstrate viral clearance during the manufacturing process for FLEXBUMIN 5%.

These studies indicate that specific steps in the manufacturing of FLEXBUMIN 5% are capable of eliminating/inactivating a wide range of relevant and model viruses. Since the mechanism of virus elimination/inactivation by fractionation and by heating steps is different, the overall manufacturing process of FLEXBUMIN 5% is effective in reducing viral load.

The likelihood of the presence of viable hepatitis viruses has been minimized by testing the plasma at three stages for the presence of hepatitis viruses, by fractionation steps with demonstrated virus removal capacity and by heating the product for 10 hours at 60°C. This procedure has been shown to be an effective method of inactivating hepatitis virus in albumin solutions even when those solutions were prepared from plasma known to be infective.1,2,3 FLEXBUMIN 5% contains no blood group isoagglutinins, thereby permitting its administration without regard to the recipient's blood group.