Clinical relevance of non-grass pollens respiratory allergies in Italy and effects of specific sublingual immunotherapy: The Rainbow Trial, a multicentre 3-year prospective observational study.

Objective: We evaluated, by means of a multicentre, prospective observational trial, the severity in term of symptoms and symptomatic drugs use and the presence of asthma in subjects with tree or cypress or olive, or ragweed or parietaria allergy and we evaluated also the efficacy of a consecutive 2-year specific sublingual immunotherapy treatment.
Patients and Method: Consecutive patients suffering of respiratory allergies (rhinoconjunctivitis and/or mild moderate asthma) due to one of the described allergens were enrolled During the specific relevant pollen seasons for each allergens nose and eye symptoms and medication scores (SS and MS) were evaluated Global score (GS) was calculated as the sum of SS and MS. An Asthma symptom score if present, were also, calculated A total of 162 patients were enrolled in 14 Italian Allergic Clinics .Patients were treated with the relevant specific sublingual immunotherapy (SLITOne, ALK) for two consecutive pollen seasons.
Results: At baseline prevalence of allergies was the following: tree 18% (30 patients); ragweed 14% (23 patients); olive 7% (11 patients); cypress 7% (12 patients) and pellitory 53% (86 patients). At baseline asthma was detected in 65 patients (40%). Asthma was more common in poli-sensitive subjects in comparison with mono-sensitive (51% vs. 300/o). According to allergen type, asthma was present in 47% of pellitory allergic patients, in 45% of olive allergic subjects, in 38% of ragweed allergic patients, in 26% of tree allergic patients and only in 9% of cypress allergic subjects. In pellitory, olive and ragweed allergic patients the frequency of asthma was statistically significant (P=0.0055) higher in comparison with other groups. At baseline GS mean (SD) in the whole population was 17(7). GS during the following 2 consecutive seasons with SLIT treatment decreased significantly (P=0.0001) to 9 (5) and to 7 (5), respectively (a reduction of 59% in comparison with baseline). In patients with asthma the mean clinical score decreased significantly from baseline value of 2. 7 to 0.3 at the end of the observation period No serious adverse events were reported Local side effects, mainly oral itching, were reported by 14% of patients and were mild and transient in nature.
Conclusion: In this population pellitory, olive and ragweed allergies are associated with a more severe clinical picture in comparison with tree and cypress allergy. A two-year SLIT treatment was associated with a significant reduction in SS, MS, GS and asthma score in comparison with baseline. SLIT was also safe and well tolerated