The effects of the nasal antihistamines olopatadine and azelastine in nasal allergen provocation.
BACKGROUND
Olopatadine, an antihistamine used in allergic conjunctivitis, is under development as a nasal preparation for the treatment of allergic rhinitis.


OBJECTIVE
To evaluate the efficacy of olopatadine in suppressing symptoms and biomarkers of the immediate reaction induced by nasal allergen provocation and to compare olopatadine with azelastine in the same model.


METHODS
The study was approved by the Johns Hopkins University institutional review board, and all subjects gave written consent. We studied 20 asymptomatic subjects with seasonal allergic rhinitis. The study had 2 randomized, double-blind, placebo-controlled, crossover phases that evaluated 2 concentrations of olopatadine, 0.1% and 0.2%. In a third exploratory phase, olopatadine, 0.1%, was compared with topical azelastine, 0.1%, in a patient-masked design. Efficacy variables were the allergen-induced sneezes, other clinical symptoms, and the levels of histamine, tryptase, albumin, lysozyme, and cysteinyl-leukotrienes (third study only) in nasal lavage fluids.


RESULTS
Both concentrations of olopatadine produced significant inhibition of all nasal symptoms, compared with placebo. Olopatadine, 0.1%, inhibited lysozyme levels, but olopatadine, 0.2%, inhibited histamine, albumin, and lysozyme. The effects of olopatadine, 0.1%, were comparable to those of azelastine, 0.1%.


CONCLUSIONS
Olopatadine, at 0.1% and 0.2% concentrations, was effective in suppressing allergen-induced nasal symptoms. At 0.2%, olopatadine provided evidence suggestive of inhibition of mast cell degranulation.
Pipkorn
Patrik
P
Division of Allergy and Clinical Immunology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.
Costantini
Candy
C
Reynolds
Curt
C
Wall
Michael
M
Drake
Margaret
M
Sanico
Alvin
A
Proud
David
D
Togias
Alkis
A
D000328:Adult; D000485:Allergens / Q000276:immunology*; D018926:Anti-Allergic Agents / Q000008:administration & dosage / Q000627:therapeutic use; D003233:Conjunctivitis, Allergic / Q000188:drug therapy* / Q000276:immunology; D018592:Cross-Over Studies; D003990:Dibenzoxepins / Q000008:administration & dosage / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006634:Histamine H1 Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009299:Nasal Provocation Tests; D000069605:Olopatadine Hydrochloride; D010793:Phthalazines / Q000008:administration & dosage / Q000627:therapeutic use*; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy* / Q000276:immunology
D000485:Allergens; D018926:Anti-Allergic Agents; D003990:Dibenzoxepins; D006634:Histamine H1 Antagonists; D010793:Phthalazines; D000069605:Olopatadine Hydrochloride; C020976:azelastine