Sublingual Immunotherapy of Birch Pollen Associated Apple Allergy
More than 70% of birch pollen allergic patients suffer from allergic reactions to certain foods, e.g. stone fruits, hazelnut and some vegetables. However, specific immunotherapy (SIT) with birch pollen extract is not effective for the treatment of associated food allergy in a substantial number of patients. Based on our previous clinical and immunological investigations of birch pollen related food allergy (BPRFA) the investigators hypothesize that for effective SIT of this abundant food allergy the disease-eliciting food allergens should be employed. To prove this concept, the investigators aim to sublingually administer the major apple allergen, Mal d 1, to birch pollen-allergic patients with concomitant apple allergy and evaluate clinical and immunological effects of this treatment. The investigators choose Mal d 1 as model food allergen because (i) its cross-reactivity with Bet v 1 has been well characterized,(ii) apple is the most frequent trigger for BPRFA and (iii) recombinant(r)Mal d 1 was well tolerated after sublingual administration to 20 birch pollen-allergic patients in a previous study. Sublingual administration of a defined concentration of GMP-rMal d 1 will be compared with equal doses of GMP-rBet v 1 as a positive control and placebo-treatment. Clinical parameters will include skin prick tests (SPT) and objective and subjective assessment of apple and birch pollen-induced allergic symptoms. Immunological parameters will comprise the analysis of antibody and T cell responses to Mal d 1 and Bet v 1 as well as the evaluation of basophil activation.
The proposed pilot study will be a first investigation of the concept to specifically treat BPRFA with the involved food allergens and thus, represents an important step in the development of an efficient and safe therapy in the future.
|Birch Pollen Related Apple Allergy Birch Pollen Allergy||Drug: rMal d 1 Drug: rBet v 1 Other: placebo drops||Phase 2|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Treatment
|Official Title:||Sublingual Immunotherapy of Birch Pollen Associated Apple Allergy|
- allergen concentration to induce allergic reactions in the oral cavity as a measure of efficacy (oral provocation test) [ Time Frame: 1 year ]To measure the clinical effects on apple-induced OAS, open food challenges (OFC) with every 30 minutes increasing doses of GMP-rMal d 1 will be performed before and after the treatment period.
- T cell proliferation and cytokine production as a measure of tolerance induction [ Time Frame: 1 year ]PBMC isolated from heparinised blood before, during and after sublingual administration of the treatment will be stimulated with titrated concentrations of rMal d 1 and rBet v 1, respectively. Proliferative and cytokine responses will be determined.
- allergen specific antibody response [ Time Frame: 1 ]measurement of IgE, IgG and IgA antibodies specific for Bet v 1 and Mal d 1
|Actual Study Start Date:||March 14, 2012|
|Study Completion Date:||December 20, 2016|
|Primary Completion Date:||February 28, 2014 (Final data collection date for primary outcome measure)|
Experimental: treatment with rMal d 1
these apple and birch pollen allergic patients are treated with daily sublingual application of 25µg recombinant Major apple allergen, Mal d 1 during 4 months
Drug: rMal d 1
25 µg daily as sublingually administered drops, 16 weeks
Active Comparator: treatment with rBet v 1
These apple and birch pollen allergic patients are treated with daily sublingual application of 25µg recombinant Major birch pollen allergen,Bet v 1 during 4 months
Drug: rBet v 1
25 µg daily administered sublingually as drops over 16 weeks
Placebo Comparator: treatment with placebo drops
These apple and birch pollen allergic patients are treated daily with placebo applied sublingually during 4 months
Other: placebo drops
25 µg of placebo Drops daily administered sublingually over 16 weeks
Please refer to this study by its ClinicalTrials.gov identifier: NCT01449786
|Medical University of Vienna|
|Vienna, Austria, 1090|
|Principal Investigator:||Barbara Bohle, PhD, Prof.||Medical University of Vienna|
|Principal Investigator:||Tamar Kinaciyan, MD||Medical University of Vienna|