Method for the preparation of immunoglobulins

A method for the preparation of a solution of immunoglobulins, wherein the method comprises the steps of:

• a) obtaining an initial solution comprising a polyether or polymer of glycol and immunoglobulins with a purity greater than or equal to 96%,
• b) adding caprylic acid or a salt thereof to the initial solution to achieve a concentration between 9 mM and 15 mM of said caprylic acid;
• c) adjusting the pH of the solution obtained in step b) to between 5.0 and 5.2;
• d) incubating the solution obtained in step c) for a time and at a temperature necessary for the inactivation of enveloped viruses;
• and
• e) performing a step of ultrafiltration/diafiltration on the solution obtained in step d).
• wherein step e) of ultrafiltration/diafiltration is carried out in two phases:
• a first phase in which the pH is adjusted to between 5.0 and 6.0 in order to reduce or eliminate most of the caprylate;
• and
• a second phase in which the pH is adjusted to a value less than or equal to 5.0, in order to reduce or eliminate most of the polyether or polymer of glycol.