Patent ID: 7887821
Filing Date: 2011-02-15
Classification: A61K

Abstract:
1. A process for producing an allergen extract from a biological allergen source material selected from the group consisting of pollen from birch trees, weeds, herbs and grass comprising the steps of a) contacting the source material with an aqueous extraction agent to produce an allergen extract mixture containing allergens dissolved in a liquid phase and a solid phase consisting of source material residues, b) subjecting the allergen extract mixture to a first separation step to remove the solid phase to produce a crude allergen extract, c) subjecting the crude allergen extract to a low molecular fraction removal step to remove molecules having a molecular size of less than 10 kDa, said low molecular fraction removal step being selected from the group consisting of an ultrafiltration step, a diafiltration step and a dialysis step, and d) carrying out step c) while measuring the conductivity continuously until the allergen extract has conductivity of less than 900 μS/cm at 25° C. to obtain a purified allergen extract.