Simplified methods for preparation of very high purity Factor VIII concentrate

In the process for preparing Factor VIII concentrate, the improvement comprising the step of precipitating fibrinogen selectively from a solution of plasma or plasma cryoprecipitate in buffer by the addition of about 4% by volume of polyol to said solution, concentrating the Factor VIII in the solution by increasing the polyol concentration to about 6% and holding the 6% polyol containing solution at from about 0.degree. to about 5.degree. until precipitation occurs and then redissolving the precipitated Factor VIII in buffer solution to yield a solution containing very high purity Factor VIII which is substantially free of contaminating foreign protein.

In a process for removing pyrogens from a buffer solution of Factor VIII the improvement comprising the addition of about 6% polyol to said solution and holding the resulting polyol containing solution at a temperature of from about 0.degree. to about 5.degree. C to thereby precipitate Factor VIII, leaving in solution the pyrogenic material.

In the concentration of Factor VIII the improvement comprising holding a solution of about 1 part of Factor VIII containing blook fraction obtained from plasma cryoprecipitation in about 3 parts of citrate buffer containing about 6% polyol at a temperature of from about 0.degree. to 5.degree. to thereby cause precipitation of Factor VIII from said solution and redissolving said Factor VIII in buffer to give a very high purity Factor VIII containing solution.