Method of purifying therapeutic proteins

A method of reducing the level of plasminogen and/or tissue plasminogen activator and/or other protease(s) in a solution comprising fibrinogen and/or Factor VIII and/or von Willebrand factor (VWF), the method comprising:

• (i) passing a feedstock comprising fibrinogen and/or Factor VIII and/or VWF through a first hydrophobic charge-induction chromatographic resin;
• (ii) recovering a solution comprising fibrinogen and/or Factor VIII and/or VWF which passes through the first hydrophobic charge-induction chromatographic resin;
• (iii) passing the solution that is recovered in step (ii) through a second hydrophobic charge-induction chromatographic resin;
• and
• (iv) recovering a solution comprising fibrinogen and/or Factor VIII and/or VWF which passes through the second hydrophobic charge-induction chromatographic resin;
• wherein the conditions of the chromatographic steps are such that the plasminogen and/or tissue plasminogen activator and/or other protease(s) is bound to the first and/or second resin, and wherein the concentration of plasminogen and/or tissue plasminogen activator and/or other protease(s) in the solution that is recovered in step (iv) is reduced by at least 50% compared to the feedstock.

A solution comprising fibrinogen, wherein:

• (a) at least 75% of the total protein of the solution comprises fibrinogen;
• (b) less than 50 pg/mg of the total protein comprises tissue plasminogen activator;
• and
• (c) less than 1 μg/mg of the total protein comprises plasminogen.

A method of producing a stable liquid fibrinogen solution, the method comprising:

• (i) passing a feedstock comprising fibrinogen through a hydrophobic charge-induction chromatographic resin under conditions selected such that plasminogen and/or tissue plasminogen activator and/or other protease(s) are bound to the resin;
• and
• (ii) recovering a solution comprising fibrinogen which passes through the resin;
• wherein the concentration of plasminogen and/or tissue plasminogen activator and/or proteases(s) in the recovered solution is reduced by at least 50% compared to the feedstock.

A method of producing a stable liquid fibrinogen solution, the method comprising:

• (i) passing a feedstock comprising fibrinogen through a first hydrophobic charge-induction chromatographic resin;
• (ii) recovering a solution comprising fibrinogen which passes through the first hydrophobic charge-induction chromatographic resin;
• (iii) passing the solution that is recovered in step (ii) through a second hydrophobic charge-induction chromatographic resin;
• and
• (iv) recovering a solution comprising fibrinogen which passes through the second hydrophobic charge-induction chromatographic resin;
• wherein the conditions of the chromatographic steps are such that plasminogen and/or tissue plasminogen activator and/or other protease(s) are bound to the first and/or second resin, and wherein the concentration of plasminogen and/or tissue plasminogen activator and/or other protease(s) in the solution that is recovered in step (iv) is reduced by at least 50% compared to the feedstock.