Study of Specific Allergen Immunotherapy in Grass Pollen Allergic Subjects by Epicutaneous Allergen Administration

Inclusion criteria: * Written informed consent * History of grass pollen allergic rhinitis * Male and female between 18 years to 65 years * Positive skin-prick test to grass pollen * Positive conjunctival provocation test Exclusion criteria: * Eczematous skin lesions on the upper arms * Perennial allergic rhinitis * Symptoms of infectious disease with rhinitis in between the last 2 weeks * Surgical intervention in between the last 30 days * Pregnancy or nursing * History of HIV or AIDS * History of mastocytosis (cutaneous or systemic) * History of significant cardiovascular disease * Hypertension (blood pressure \> 160 / 95) * History of significant pulmonary, renal and/or hepatic disease * History of significant hematological disorder * Moderate or severe asthma * History of malignancy * History of neurological or psychiatric disease * History of autoimmune disease * Antihistamines with longed half-lives in the last week * Systemic or topical steroids for 5 days * Active infectious disease * Contraindicated medications: * immunosuppressive agents * Betablockers * ACE-inhibitors, AT 2 Antagonists * tricyclic antidepressants * daily use of Beta-agonists or steroid inhalers * Participation in another clinical trial /study at the moment or within the last 60 days