Calcium phosphate adjuvanted allergens.

Calcium phosphate has been used for many years as an adjuvant for vaccines. Results of field trials using calcium phosphate in several countries have been published and demonstrate high immunogenicity and the absence of untoward reactions. This paper presents preliminary results of studies on the use of calcium phosphate, instead of aluminum compounds, for preparing adsorbed allergens. These were performed with purified house dust, mite, and grass pollen extracts. Immunotherapy with house dust and mite extracts gave a high rate (70%) of satisfactory therapeutic results. Efficacy was compared with immunization carried out with fluid preparations under the same conditions. It was found that satisfactory results were of the same order, but elicited a higher number of injections. Immunotherapy with calcium phosphate adjuvanted allergens was also equal, as with aluminium adjuvanted allergens, according to published data. Good tolerance was noted for adsorbed grass pollen extracts, but clinical evaluation of results can only be reported after treatments during at least three seasons.