PURETHAL Birch RUSH Study

Inclusion Criteria: * Signed informed consent. * Age ≥12 years. * Allergic rhinitis/rhinoconjunctivitis related to birch pollen with or without concomitant mild to moderate persistent asthma * FEV1\>70% for patients with a history of mild to moderate asthma, FEV1\>70% or PEF\>80% for patients without a history of asthma * A positive SPT (mean wheal diameter ≥ 3mm compared to negative control and negative control should be negative) for birch pollen. * Positive serum specific anti-birch IgE-test (\>0.7 U/ml) within 1 year before randomization and/or a positive provocation test for birch pollen within 1 year before randomization. Exclusion Criteria: * Immunotherapy (SCIT or SLIT) with birch pollen allergens within the past 5 years * Any specific immunotherapy (SCIT or SLIT) during the study period * Severe immune disorders (including auto-immune diseases) and/or diseases requiring immunosuppressive drugs * Active malignancies or any malignant disease within the past 5 years * Severe uncontrolled diseases that could increase the risk for patients participating in the study * Acute/active inflammation or infection of the target organs at the start of the study * Secondary changes of the target organ * Diseases with a contraindication for the use of adrenaline * Use of systemic steroids within 4 weeks before start of the study and during the study * Treatment with systemic and local β-blockers * Vaccination within one week before start of therapy or during the initiation phase * Anti-IgE therapy within the 6 months prior to inclusion and during the study * Participation in a clinical study with a new investigational drug within the last 3 months or for a biological within the last 6 months prior to or during the study * Pregnancy, lactation or inadequate contraceptive measures for women of child-bearing age * Alcohol, drug or medication abuse within the past year * Any clinically significant abnormal laboratory parameter at screening * Lack or expected lack of cooperation or compliance * Severe psychiatric, psychological, or neurological disorders * Patients who are employees of the sponsor, institution or 1st grade relatives or partners of the investigator