A process for the preparation of finely divided - optionally suspended in a carrier - microparticles of tyrosine with an allergen dispersed therein.

摘要

1377074 Allergen preparations BEECHAM GROUP Ltd 6 July 1972 [13 July 1971] 32780/71 Heading A5B Finely divided micro-particles of tyrosine having an allergen dispersed therein are prepared by mixing a solution of tyrosine in a strong aqueous acid with an aqueous or watermiscible solution of the desired allergen and simultaneously or subsequently neutralising (i.e. adjusting the pH to from 4 to 7) the resultant --solution, thereby precipitating the required finely divided micro-particles of tyrosine containing the allergen, and subsequently separating the micro-particles. The acid may be hydrochloric, nitric, sulphuric or phosphoric acid and the base used to neutralise the solution is preferably sodium hydroxide. The allergen may be present in an entirely aqueous medium or in an aqueous medium containing one or more water-miscible solvents, e.g. glycerol. The allergen solution may comprise allergenic extracts of whole allergens such as pollens, house dust. cat fur or dog hair. The precipitate of tyrosine containing the allergen may be removed from the solution by centrifugation or filtration and resuspended in a liquid physiologically acceptable carrier, e.g. phenol-saline to produce an injectable composition for use in densensitisation therapy.