The objective of the study was to evaluate in routine practice the benefits of sublingual allergen immunotherapy (SLIT) for allergic patients with allergic rhinitis (AR), with or without asthma, according to various methods of use (treatment regimen: formulation type, dose, duration, initiation) and type of allergen (grass pollen, tree pollen, herbaceous pollen, house dust mites, animal dander, moulds and poly-reactive types).

The treatment considered was any SLIT (tablet or liquid forms) accepted by the patient and the parent(s) in the case of minor patients. The treatment was taken as prescribed by the observing physician.

The expected benefits for patients after approximately 6 and 12 months after initiation of SLIT included:

• Decreased intensity of symptoms
• Decreased discomfort
• Decreased consumption of symptomatic treatments or associated treatments (especially in asthmatic patients)
• Improved quality of life
• Reduced absenteeism from school or work
• Beneficial impact on leisure activities.

Inclusion Criteria:

• Patients aged 5 years or older
• Patients with a respiratory allergy with significant clinical symptoms and whose diagnosis was confirmed by a positive skin prick-test and/or the presence of specific IgE antibodies to one or more allergens implicated in the symptoms
• Patients eligible for AIT (patients who had been treated with AIT in the 3 years prior to the inclusion visit could be included if starting a new form and/or type of AIT)
• Patients previously treated with a pharmacological AR treatment in the month before the inclusion visit or during the previous pollen season, and requiring the initiation of AIT
• Patients (and/or their parents or legal representatives as appropriate) agreeing to take part in the study after having been informed orally and in writing by the observing physician.

Exclusion Criteria:

• Patient with a hypersensitivity (allergy) to any of the excipients in the selected AIT
• Patients taking beta-blockers (including local treatments, e.g. eye drops)
• If asthmatic patient:
• Patients with uncontrolled (unstable) or severe asthma (in adults this was defined as daily symptoms and FEV1 <70% of the theoretical value after appropriate drug treatment, and in children and adolescents by FEV1 <80% of the theoretical value after appropriate drug treatment)
• Patients who have had a severe asthma exacerbation in the last three months
• Asthmatic patient with unresolved acute infection of the airways.

The target population included adult patients, adolescents and children (aged ≥5 years) with an allergy to one or more allergens confirmed by a positive skin prick-test and/or the presence of specific IgE antibodies, and eligible for AIT.