Process for producing an allergen extract

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, wherein said low molecular fraction removal step comprises at least one member selected from the group consisting of an ultrafiltration step, a diafiltration step and a dialysis step, and
• d) carrying out step c) until the allergen extract has conductivity of below 2000 μS/cm at 25° C. to obtain a purified allergen extract.

A process for producing an allergen extract from a biological allergen source material which comprises grass pollen 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, and
• d) carrying out step c) until the allergen extract has conductivity of below 2000 μS/cm at 25° C. to obtain a purified allergen extract.