From Reuters Health Information
By Scott Baltic
NEW YORK (Reuters Health) Sep 29 - A high-dose sublingual tablet containing allergens produced by the pollen of five grass species significantly decreases common allergy symptoms compared with placebo, from the first month of treatment forward, according to a report in the September issue of the Journal of Allergy and Clinical Immunology.
The immunotherapy tablet, Oralair Grasses, includes allergen extracts from five grasses: orchard, meadow, perennial rye, sweet vernal and timothy grasses. Oralair Grasses is manufactured by Stallergenes, Antony, France and marketed in Europe. It is not yet approved for use in the United States.
The tablet is safe and easy for patients to use, Dr. Friedrich Horak of the Medical University of Vienna, Austria told Reuters Health by e-mail, and is potent over a short treatment period, though only for grass pollen allergies. The once-daily treatment, he added, gives the advantage of good patient compliance.
The study is reportedly the first to evaluate the efficacy and onset of action of this desensitization tablet in an allergy challenge chamber. The chamber provides controlled conditions for measuring individuals' responses to a specific allergen concentration for a set period of time.
The randomized, placebo-controlled, double-blind trial recruited 89 participants between 18 and 50 years of age with histories of seasonal grass-pollen allergies. The 45 subjects in the treatment group received one immunotherapy tablet daily for the four month trial period.
Each participant underwent a two-hour baseline grass-pollen allergen challenge in the chamber before treatment began, and then again at one week and one, two and four months after starting treatment.
The primary outcome was the participants' average rhinoconjunctivitis total symptom score, which measures sneezing, runny nose, itchy nose, nasal congestion, itchy eyes and tearing.
A statistically significant improvement was seen in the treatment group after the first month, which was maintained at two and four months. Further, the total symptom score in the treatment group decreased at each successive challenge. In the patients showing the best clinical response to treatment, specific IgG (but not IgE) values were higher.
There were no serious adverse events.
J Allergy Clin Immunol 2009;124:471-477.
