8. Clinically relevant sensitivity against seasonal allergens [mountain cedar, ash, birch, elm, maple, hickory, oak, cottonwood, bermuda grass and grass mix] documented by a positive case history, prick test wheal size ≥3 mm in diameter larger than the negative control or radioallergosorbent test with class ≥2. Exceptions: some or all of the listed allergens must not be tested if they are not common to the Investigator´s region or, if common to the region, no overlap exists between the allergen(s) season and the treatment and post treatment phase of the study. Furthermore, subjects will not be excluded if the Investigator may judge the sensitivity as not clinically relevant.