This is a dose finding study and no therapeutic study. Patients will receive in 4-weekly intervals 6x 0,5mL of one of 4 different concentrations of Depigoid Phleum. The study is performed outside the pollen season. Thus the aim of the study is not the therapeutic effect of the specific immunotherapy (effect on allergy specific symptoms during the pollen season) but the effect on the Conjunctival provocation test (CPT). According to the EMA "Guideline on clinical development of products for specific immunotherapy for the treatment of allergic diseases" provocation tests are accepted as primary outcomes for dose-finding studies.
For the CPT increasing doses of Phleum pollen solutions are applied to the eye and characteristic symptoms (eye redness, weeping, itching or burning, and nose dripping/blockage) are assessed at each concentration: 0=absent, 1=mild, 2=moderate, 3=severe. At a score value of >=5/concentration the test is considered positive and finished.
It is expected that at the end of the study higher doses are necessary to provoke a positive CPT.
Furthermore comparative evaluation of the safety data (AEs) in the different dosage groups is a very important parameter for the evaluation of the outcome of the study.