Method of developing a process for producing an allergen extract

The present invention relates to a method of developing a process for producing an allergen extract from a biological allergen source material comprising the steps of a) subjecting the source material to a first extraction and purification process to produce a first purified allergen extract, b) subjecting the first purified allergen extract to one or more toxicity tests to examine the first purified allergen extract for a potential content of one or more toxic components, c) if the toxicity test shows that the toxic component has not been removed, subjecting the allergen extract to a first modified extraction and purification method to produce a first modified purified allergen extract, d) subjecting the first modified purified allergen extract to one or more toxicity tests to examine the first modified purified allergen extract for a potential content of one or more toxic components, e) repeating step c) to d) until the toxic component has been removed to identify an extraction and purification method, which removes the potential toxic component.