Intralymphatic immunotherapy: a 3-year randomized, double-blind study in
72 patients with allergic rhinitis due to birch and grass.
Abstract
Background: There is need for a fast, efficient, and safe way to induce
tolerance in patients with allergic rhinitis. Methods: Patients with
birch and timothy allergy were randomized and received three doses of
0.1 ml of birch and 5-grass allergen extracts (10,000 SQ units/ml,
ALK-Abelló), or birch and placebo or 5-grass and placebo by
ultrasound-guided injections into inguinal lymph nodes at monthly
intervals. Rhinoconjunctivitis Total Symptom Score, Medication Score and
Rhinoconjunctivitis Quality of Life Questionnaire were evaluated before
treatment and after each birch and grass pollen season during three
subsequent years. Circulating proportions of T helper subsets and
allergen-induced cytokine and chemokine production were analyzed by flow
cytometry and Luminex. Results: The three groups reported fewer
symptoms, lower use of medication and improved quality of life during
the birch and grass pollen seasons each year after treatment at an
almost similar rate independently of treatment. Nine patients had severe
adverse events which were judged to be unrelated to the therapy. Mild
local pain was the most common adverse event. IgE levels to birch
decreased, whereas birch-induced IL-10 secretion increased independently
of treatment. IgG4 levels to birch and timothy and skin prick test
reactivity remained mainly unchanged. Conjunctival challenge tests with
timothy extract showed a higher threshold for allergen. In all three
groups, regulatory T cell frequencies were increased three years after
treatment. Conclusion: Intralymphatic immunotherapy against grass and
birch pollen allergy was effective, safe and associated with bystander
immune modulatory responses.