Azelastine eye drops reduce and prevent allergic conjunctival reaction and exert
anti-allergic activity.
Author(s): Ciprandi G, Buscaglia S, Catrullo A, Pesce G, Fiorino N, Montagna P, Bagnasco M,
Canonica GW.
Affiliation(s): Department of Internal Medicine, University of Genoa, Italy.
Publication date & source: 1997, Clin Exp Allergy. , 27(2):182-91
BACKGROUND: Azelastine is a selective H1-receptor antagonist, which has
previously been demonstrated to be effective in the treatment of allergic
rhinitis. We have recently demonstrated that nasal azelastine inhibits the
clinical and inflammatory events following nasal allergen challenge.
Particularly, we focused our attention on ICAM-1 expression on epithelial cells,
since it is the natural ligand of LFA-1, an adhesion molecule expressed by
leucocytes, including eosinophils.
OBJECTIVE: Since azelastine ocular drops are now available, the aim of the
present study was the evaluation of the anti-allergic activity in the model of
allergen specific conjunctival challenge (ASCC).
METHODS: Twenty outpatients with allergic rhinoconjunctivitis due to Parietaria
Judaica (Wall Parietary) were included outside the pollen season. The study was
designed as randomized, placebo-controlled, double-blind and parallel group,
developed in two parts. The former investigated the onset of effect of a single
dose of azelastine eye drops administered 20 min after clinical response due to
ASCC. The latter evaluated the clinical and inflammatory parameters following
ASCC after 7-days treatment with azelastine. Clinical parameters (hyperaemia,
itching, lacrimation and eyelid swelling) were evaluated at baseline, 5, 10, 20
and 30 min (i.e. early phase reaction-EPR) and 6 h (i.e. late phase reaction-LPR)
after ASCC. Cytological assessment (number of neutrophils, eosinophils. monocytes
and lymphocytes) and ICAM-1 expression on conjunctival epithelial cells were
evaluated at baseline, 30 min (i.e. early phase reaction-EPR) and 6 h (i.e. late
phase reaction-LPR) after ASCC.
RESULTS: When administered 30 min after ASCC, azelastine produced a clinical
effect ranging between 10 and 20 min after eye drops administration (P < 0.01).
After 7 days of treatment, 30 min after ASCC, azelastine induced a reduction of
symptom scores during EPR and LPR (P < 0.01), a reduction of inflammatory cell
infiltration during both EPR (P < 0.01) and LPR (P < 0.01), and a reduction of
ICAM-1 expression during EPR and LPR (both P < 0.01). Placebo did not modify any
of the studied parameters.
CONCLUSION: Azelastine eye drops exert anti-allergic activity, inducing a rapid
improvement of clinical events when administered after ASCC, and reducing both
symptoms and cellular infiltration when administered before ASCC. Finally,
azelastine down-regulates ICAM-1 expression on epithelial conjunctival cells,
confirming the results obtained at nasal level.
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