A Randomised, Double-blind, Placebo Controlled Study With Oralgen Grass Pollen Rhinoconjunctivitis

Inclusion Criteria: * male or female * grass pollen related rhinoconjunctivitis symptoms for at least the last 2 pollen seasons * positive skin prick test RRTSS greater or equal to 12 during the 2008 season * signed informed consent Exclusion Criteria: * positive skin prick test for other environmental allergens and suffering from serious allergic symptoms * clinical history of significant symptomatic allergic rhinitis due to tree/weed pollen which potentially overlap the grass pollen season * clinical history of symptomatic perennial allergic rhinitis caused by an allergen to which the patient is regularly exposed * lacking of good health * abnormal spirometry * lower respiratory tract infection * asthma requiring treatment other than beta-2 agonists * oral steroids within 12 weeks before screening * regular contraindications for use of immunotherapy