The study will evaluate the efficacy and safety of BM32 in grass pollen allergic subjects. It will test the hypothesis that either of two doses of BM32 will lead to a sustained relief off allergy symptoms over a two year study period.

The present study is designed to evaluate the efficacy and safety of a treatment with the recombinant vaccine BM32 during two consecutive grass pollen seasons. Efficacy evaluation will be performed on the basis of allergy symptoms and use of relief medication as well as based on immunological parameters. After patient assessment during a screening season, patients will be randomized to one of two doses of BM32 or placebo. Patients will receive three injections of BM32 pre-season and one post-season boost injection to maintain optimal allergen specific IgG responses. Outcome will be measured after both seasons individually.

Inclusion Criteria:

• Positive history of grass pollen allergy
• Positive skin prick test reaction to grass pollen extract
• Grass pollen specific IgE and rPhl p 1/rPhl p 5 specific IgE (>3 kUA/L)
• Moderate to severe symptoms of grass pollen allergy during pollen peak

Exclusion Criteria:

• Symptomatic perennial allergies

• Atopic dermatitis

• Pregnancy or breast feeding

• Women with childbearing potential not using medically accepted birth control

• Autoimmune diseases, immune defects, immune suppression

• Immune complex induced immunopathies

• Contra indications for adrenaline

• Severe general maladies, malignancies

• Patients on long-term systematic corticosteroids, immune suppressive drugs, tranquilizers or psychoactive drugs

• Contra indication for skin prick testing

• Bronchial asthma not controlled by low dose inhaled corticosteroids

• Chronic use of beta blockers

• Participation in another clinical trial within one month prior to study

• Participation in SIT trial in 2 years prio to study

• Patients who had a previous grass pollen SIT

• Risk of non-compliance with study procedures

• Use of prohibited medications

  • Depot corticosteroids - 12 weeks prior to enrolment
  • Oral corticosteroids - 8 weeks prior to enrolment
  • High dose inhaled corticosteroids - 4 weeks prior to enrolment
  • Use of H1 antihistamines 3 days prior to enrolment