Safety and Efficacy of an Allergen Vaccine in Grass-Pollen Allergy

Inclusion Criteria: 18 to 65 years of age Mild to moderate seasonal allergic rhinoconjunctivitis due to sensitization against grass pollen as evident from history (≥ 2 years), and positive nasal provocation test (NPT) and positive skin prick test (SPT, wheal ≥ 3mm larger than diluent) to grass pollen extract Female participants must meet one of the following criteria: No reproductive potential due to menopause (one year without menses, in case of doubts serum FSH will be determined and must be >40 U/mL), hysterectomy, bilateral oophorectomy, or tubal ligation. Patient agrees to consistently practice an effective and accepted method of contraception throughout the duration of the study and for 1 additional months after the last immunization (hormone-based, or intrauterine device, or double barrier contraception, i.e. condom + diaphragm, condom or diaphragm + spermicidal gel or foam) Written informed consent Patient is willing and able to comply with all trial requirements Exclusion Criteria: Additional allergies (seasonal or perennial) of which the symptoms overlap temporally with the screening and treatment period Contraindication to Allergen Preparation Contraindication for Nasal Provocation Test Contraindication for Skin Prick Test Actual significant obstructive pulmonary disorder (FEV1< 70%) Pharmacological treatment that could affect allergic sensitivity during the trial Presence or history of significant cardiovascular, renal, pulmonary, endocrine, autoimmune, neurological, and psychiatric disease as judged by the investigator Serum test positive for HIV, HBV, or HCV Current diagnosis or history of malignancy; presence of suspicious lymphadenopathy or splenomegaly on physical examination Pregnancy or lactation Blood donation within 30 days before enrolment History of abuse of alcohol or other recreational drugs Specific immunotherapy against pollen allergy within the last two years Intake of an investigational drug within three month before enrolment Intake of contraindicated medicaments for SIT as Betablockers, ACE/ATII Inhibitors