PURETHAL Grasses Rush Study

Inclusion Criteria * Patients with rhinitis or rhinoconjunctivitis, with or without mild asthma (FEV1 \> 70%) for at least 2 years related to grass pollen, eligible for SCIT. * Confirmation of IgE-mediated allergy by means of: * Positive SPT to grass pollen (mean wheal diameter ≥ 3 mm and negative control truly negative (no reaction), or * Specific serum IgE-test (ssIgE \>0.7 U/ml) for grass pollen, or * Positive provocation test for grass pollen. * Age ≥ 18 years. * Patients have given a written informed consent Exclusion Criteria: * Chronic asthma or emphysema, particularly with a FEV1 ≤ 70% of predicted value. * Serious immuno-pathological diseases or malignancies (including auto-immune diseases, tuberculosis, HIV). * Active inflammation/infection of the target organs (nose, eyes, lungs). * Severe atopic dermatitis in need for systemic immunosuppressive medication. * Symptomatic coronary heart diseases (e.g heart failure, recent myocardial infarction, unstable angina, serious arrhythmias) or severe (even under treatment) arterial hypertension. * Severe kidney disease. * Diseases with a contra-indication for the use of adrenaline. * Treatment with systemic or local beta-blockers or immunosuppressive drugs. * History of life threatening anaphylactic events, including anaphylactic food allergy, insect venom anaphylaxis, exercise or drug induced anaphylaxis. * Any specific immunotherapy (including sublingual) during the study period or during the previous 3 years for a period longer than three months. * Participation in a clinical study with a new investigational drug within the last three months. * Pregnancy, lactation or inadequate contraceptive measures (adequate measures: oral contraceptives, IUD, condom use if used together with a spermicide and having no sexual relationship with a man). * Alcohol or drug abuse. * Lack of co-operation or severe psychological disorders. * Completed or ongoing long-term treatment with tranquilizer or psycho active drugs. * Low compliance or inability to understand instructions/study documents. * Completed or ongoing treatment with anti-IgE-antibody. * Patients being in relationship or dependence with the sponsor or investigator. * Allergy to any of the excipients. * Severe illness or any other condition, which makes the patient, in the opinion of the investigator, unsuitable for the study.