This invention relates to a new process for obtaining an IgG composition from an IgG solution partly purified from human plasma, in which by applying intermediate heat treatment and without using reagents to precipitate high molecular weight aggregates/polymers and/or proteins virtually total elimination of the IgG polymers generated during the process is achieved. Furthermore this process offers high productivity, lower production costs and is easy to implement in comparison with the processes of the known art. In addition to this, by using this process stability is imparted to the final product in liquid.
