Contribution to safety of immunoglobulin and albumin from virus partitioning and inactivation by cold ethanol fractionation: a data collection from Plasma Protein Therapeutics Association member companies.

Background: Virus removal by partitioning into different fractions during cold ethanol fractionation has been described by several authors, demonstrating that cold ethanol fractionation can provide significant contribution to virus removal, even in those cases where virus removal is limited and must be supported by additional measures for virus inactivation during further processing.

Study Design And Methods: Plasma Protein Therapeutics Association (PPTA) member companies collected and evaluated 615 studies on virus removal by the steps of the cold ethanol fractionation process. The studies describe the precipitation and separation of Fraction (F)III or FI/III in the immunoglobulin fractionation process and precipitation and separation of FII/III, FI/II/III, and FIV/IV in the albumin fractionation process.

Results: The data indicate a significant contribution of cold ethanol fractionation to the overall clearance of a broad spectrum of viruses, at varied process variables such as pH, temperature, and alcohol concentration and demonstrate the robustness of virus removal by the cold ethanol fractionation process.

Conclusions: The data presented here support the importance of the partitioning steps for virus safety for immunoglobulins and albumin. However, virus removal by cold ethanol fractionation alone cannot provide viral safety of human albumin and immunoglobulins and therefore must be completed by other virus inactivation and removal procedures.