Preparation and viral inactivation of cryoprecipitate in blood banks in resource‐limited countries

Abstract

Non‐virally inactivated cryoprecipitate prepared by blood banks is still used in many countries, especially in the developing world, for the treatment of bleeding disorders due to factor VIII (FVIII), von Willebrand factor (VWF), or fibrinogen deficiency. As a consequence, patients receiving cryoprecipitate are at high risk of being infected by plasma‐borne viruses, such as HIV, and hepatitis B virus (HBV) or C virus (HCV). It is therefore urgent to develop easy‐to‐use, affordable and efficient methods for the viral inactivation of cryoprecipitate under conditions that ensure good maintenance of its haemostatic properties. Preparation of cryoprecipitate from large‐pool solvent‐detergent (SD) plasma seems not economically or technically feasible in developing countries. Cryoprecipitate prepared from single‐donor plasma virally inactivated by methylene‐blue/illumination has significantly reduced content of factor VIII and fibrinogen. There are no data on the quality of cryoprecipitate produced from plasma virally inactivated by techniques in development such as S‐51 psoralen/UV irradiation or by riboflavin/UV irradiation, but loss of FVIII and fibrinogen is reported in S‐51/UV‐treated plasma. Dry‐heat treatments of smallpool cryoprecipitate or intermediate‐purity factor VIII have been developed for use by blood banks, but they are not much used and some have not stopped the risk of transmission of HCV. Recently, a mini‐pool process and a closed bag system to perform SD treatment of cryoprecipitate have been developed for use by blood banks. Recovery of factor VIII, VWF, and fibrinogen is over 95%. Viral validation studies revealed reduction factors of > 4·17, > 4·73, and > 4·72 for HIV, BVDV, and PRV, respectively, within a few minutes of treatment. The SD bag system is in the process of CE‐marking and field testing should start in the near future.