Placebo was given the same way as a sublingual preparation.

Sublingual application containing allergen extracts of 6 grass pollen species (Holcus lanatus, Dactylus glomerata, Lolium perenne, Phleum pratense, Poa pratensis, Festuca pratensis) pollen allergen extract.

The study solution was applied sublingually, kept under the tongue for 3 minutes, and swallowed thereafter. Initial treatment was applied on the first day of treatment with a starting dose of 25% of the maintenance dose. Increasing doses of 50% were applied with the second and 100% with the third dose to give the maximum (=maintenance) dose. This was followed by a daily patient selfadministered treatment with the maintenance dose.

Solution for sublingual application containing allergen extracts of 6 grass pollen species (Holcus lanatus, Dactylus glomerata, Lolium perenne, Phleum pratense, Poa pratensis, Festuca pratensis) pollen allergen extract.

The study solution was applied sublingually, kept under the tongue for 3 minutes, and swallowed thereafter.

The primary endpoint is the change of the area under the curve (AUC, derived from an analysis period of 42 days) of the daily sum of the Symptom and Medication Score (SMS) from the baseline measurement to the measurement after 1.5 years of therapy.

Patients' Assessment of severity of symptoms at the end of each season on a 10 points visual rating scale (VRS)