Abstract: A novel method of protecting blood coagulation factor IX from proteases during purification or storage is disclosed. High concentrations of one or more water soluble organic or inorganic salts are used to stabilize factor IX, contained within blood plasma-derived solutions, or contained within solutions derived from other sources, against conversion to clinically unacceptable peptide structures such as factor IXa, and/or degraded factor IX peptides. The technique is useful in stabilizing intermediate purity factor IX preparations during purification, and in maintaining the integrity of purified factor IX during long term storage. Stable high specific activity factor IX preparations are also disclosed.

Abstract: A method using diafiltration to prepare a blood product is described. The method removes contaminating plasma proteins from whole blood or blood products. Diafiltration may be used on paraformaldehyde-fixed platelets to remove formaldehyde to undetectable levels, and to suspend the platelets into a formulation buffer suitable for subsequent treatment, such as lyophilization. The manufacturing procedure can be divided into three steps, a first diafiltration, fixation, preferably with paraformaldehyde, and a second diafiltration. In the first step, plasma proteins are removed from fresh or stored platelets or blood cells. The technique is gentle to prevent the activation and aggregation of the platelets. Fixation stabilizes the platelets to withstand freezing, lyophilization and subsequent reconstitution, and also provides a viral and bacterial reduction.