Immunotherapy with a calcium phosphate-adsorbed five-grass-pollen extract in seasonal rhinoconjunctivitis: a double-blind, placebo-controlled study

• Published in: Clinical and experimental allergy Vol. 31; no. 7; pp. 988 - 996
• Main Authors: Leynadier, F., Banoun, L., Dollois, B., Terrier, P., Epstein, M., Guinnepain, M.-T., Firon, D., Traube, C., Fadel, R., André, C.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford, UK Blackwell Science, Ltd 01-07-2001; Blackwell; Wiley Subscription Services, Inc
• Subjects: Adolescent; Adult; allergic rhinitis; Biological and medical sciences; calcium phosphate; Calcium Phosphates; Conjunctivitis, Allergic - therapy; Desensitization, Immunologic - methods; Double-Blind Method; Female; grass pollen; Host-tumor relations. Immunology. Biological markers; Humans; Immunoglobulin E - blood; Immunoglobulin G - blood; Immunosorbents; Male; Medical sciences; nasal provocation test; Nasal Provocation Tests; Phytotherapy; Plant Extracts - immunology; Plant Extracts - therapeutic use; Poaceae - chemistry; Poaceae - immunology; Pollen - chemistry; Pollen - immunology; Pollen - therapeutic use; Rhinitis, Allergic, Perennial - pathology; Rhinitis, Allergic, Perennial - therapy; skin prick test; Skin Tests; specific IgE; specific IgG4; specific immunotherapy; Treatment Outcome; Tumors; Allergy; Monocotyledones; Nose disease; Rhinitis; Conjunctiva disease; Conjunctivitis; Gramineae; Immunotherapy; Angiospermae; ENT disease; Clinical trial; Pollen; Human; Immunopathology; Desensitization; Calcium phosphate; Eye disease; Treatment; Adsorption; Placebo; Double blind study; Spermatophyta; Application method; Aeroallergen; Allergen
• ISSN: 0954-7894; 1365-2222
• DOI: 10.1046/j.1365-2222.2001.01145.x

Background Calcium phosphate‐adsorbed allergen extracts are used for subcutaneous immunotherapy to avoid the use of aluminium adjuvants.
Objectives A double‐blind, placebo‐controlled study was performed in order to confirm the safety and assess the efficacy of a standardized five‐grass‐pollen extract adsorbed onto calcium phosphate for specific immunotherapy (IT).
Methods Twenty‐nine patients with seasonal rhinoconjunctivitis were randomized to receive either the active preparation (16 patients) or placebo (13 patients), in a 1‐year study. During the increasing dose phase, an extract ranging from 0.1 IR per ml to 50 IR per ml was administered at a rate of one subcutaneous injection per week until a maintenance dose was reached. The patients were assessed by symptom diary and rescue medications during seasonal exposure and specific nasal and skin reactivity before and after IT. Immunological parameters (specific IgE and IgG4 antibodies) were assessed before, during and after IT.
Results The overall symptoms score (mean AUC) was not significantly different between the IT group and the placebo group during grass‐pollen exposure (49.6 vs. 56, respectively). The total medication score (mean AUC) was significantly lower in the IT group than in the placebo group (11 vs. 41, P < 0.01, Mann–Whitney U‐test). The cumulative symptom/medication score was significantly lower in the IT group than in the placebo group (64.5 vs. 102.3, P < 0.05, U‐test). A significant increase in nasal reactivity threshold was observed after IT in the IT group (21. 4 IR/mL before IT vs. 63.4 IR/mL after IT, P < 0.01, Wilcoxon), whereas no significant changes were observed in the placebo group (31.0 IR/mL before IT vs. 37.7 IR/mL after IT). IT induced a significant reduction in grass pollen cutaneous reactivity in the actively treated group (P < 0.001). A significant increase in serum‐specific IgG4 antibody response was observed in the IT group (3.1% before IT vs. 10.1% after IT, P < 0.001). Nine patients in the IT group developed moderate immediate systemic reactions vs. two patients in the placebo group.
Conclusion Specific immunotherapy with calcium phosphate‐adsorbed standardized grass pollen extract was safe and effective for the treatment of patients with seasonal allergic rhinoconjunctivitis.