SAFETY, COMPLIANCE AND EFFICACY OF SPECIF IC IMMUNOTHERAPY BY AQUEOUSCALCIUM-PHOSPHATE ADSORBED ALLERGEN EXTRACTS - RETROSPECTIVE STUDY

Allergen extracts adsorbed onto calcium phosphate has been used for sp ecific immunotherapy (SIT) for more than 10 years in France. In order to evaluate the safety and compliance of patients as well as the inves tigators' assessment of the efficacy of: SIT, we conducted a multicent re retrospective survey concerning patients desensitized for at least 1 year for a documented respiratory allergy. A similar survey was cond ucted simultaneously in patients desensitized by aqueous allergens. Se ven hundred and forty-seven questionnaires were analysed, 402 concerni ng patients treated with calcium phosphate adsorbed allergens and 345 concerning patients treated with aqueous allergens. The frequency of l ocal reactions (as % of total number of injections) was 1.9 per cent ( induction) 2.4 per cent (maintenance) in the calcium phosphate group a nd 2.1 per cent (induction) and 1.8 per cent (maintenance) in the aque ous group. The frequency of systemic reactions was 0.2 per cent (induc tion) and 0.3 per cent (maintenance) in the calcium phosphate group, v ersus 1.5 per cent (induction) and 0.6 per cent (maintenance) in the a queous group. Severe or moderate systemic reactions were observed in 7 0 per cent of cases during rush desensitization by aqueous extracts. N ine case of anaphylactic shock were reported in the group treated with aqueous extracts and 1 case in the group treated with calcium phospha te. Evaluation of the efficacy of SIT in patients treated for 3 years, indicated a significant improvement of the overall score (symptoms medication), in perennial rhinitis (p < 0.001), asthma (p < 0.01) and seasonal rhinitis (p < 0.01), in the 2 groups. In conclusion, this ret rospective study shows that allergen extracts adsorbed onto phosphate are locally tolerated just as well as aqueous extracts, they induce fe wer systemic reactions and have a similar efficacy to that of aqueous extracts.