title: Evaluation of the onset and duration of effect of azelastine eye drops (0.05%) versus placebo in patients with allergic conjunctivitis using an allergen challenge model.
abstract: OBJECTIVE
  The trial evaluated the effectiveness of the investigational antihistaminic and antiallergic compound Azelastine Eye Drops (AZE) in the treatment of allergic conjunctivitis using an allergen challenge model.
  
  
  METHODS
  Randomized, double-blind, placebo-controlled, paired-eye study.
  
  
  METHODS
  Adults with a history of allergic conjunctivitis (>/=2 years) who were asymptomatic throughout the trial, had a positive skin test (cat dander, grass, or ragweed pollen within the last year), and had a positive conjunctival reaction (score 2+ or more for itching and redness in both eyes on a 0-4 scale) during two separate conjunctival provocation tests (CPT) before randomization.
  
  
  METHODS
  Eighty patients underwent a 2-week screening period (visits 1 and 2) that included a CPT during visit 1 to establish the allergen threshold dose and a second confirmatory CPT performed at visit 2. Eye symptom assessments for itching (evaluated by patient) and conjunctival redness (evaluated by physician) were performed 5 and 10 minutes after CPT using a 5-point scale (from 0 = none to 4+ = severe). Qualified patients were randomized to receive one drop of AZE (0.015 mg of azelastine hydrochloride) in one eye and one drop of placebo in the other eye 20 minutes before CPT at visit 3 (onset) and 8 or 10 hours before CPT at visit 4 (duration).
  
  
  METHODS
  Individual severity scores for itching (evaluated by patient) and conjunctival redness (evaluated by physician) for each eye at 3, 5, and 10 minutes after CPT at visits 3 and 4 using a 5-point scale (0 = none to 4+ = very severe).
  
  
  RESULTS
  Each of the 80 randomized patients completed the trial. Mean itching and conjunctival redness scores at visit 3 (onset) were significantly lower (P: < 0.001) in the AZE-treated eyes than in the placebo-treated eyes. At visit 4 (duration), mean itching and conjunctival redness scores (P: </= 0.003) for the 8-hour group and mean itching scores (P: </= 0.001) for the 10-hour group were significantly lower in the AZE-treated eyes than in the placebo-treated eyes. Significant differences in mean tearing and chemosis severity scores were also seen at visit 3 (onset) and visit 4 (duration) in the AZE-treated eyes when compared with the placebo-treated eyes. Treatment with AZE was well tolerated.
  
  
  CONCLUSIONS
  Therapy of experimentally induced allergic conjunctivitis with AZE was highly effective, with an onset of action seen within 3 minutes and a duration of effect of at least 8 to 10 hours.
authors.affiliation: Department of Ophthalmology, Scripps Clinic, La Jolla, California, USA.mfried@scrippsclinic.com
authors.forename: M H
authors.initials: MH
authors.lastname: Friedlaender
authors.forename: J
authors.initials: J
authors.lastname: Harris
authors.forename: N
authors.initials: N
authors.lastname: LaVallee
authors.forename: H
authors.initials: H
authors.lastname: Russell
authors.forename: J
authors.initials: J
authors.lastname: Shilstone
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000485:Allergens / Q000009:adverse effects*; D018926:Anti-Allergic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D003228:Conjunctiva / Q000187:drug effects* / Q000473:pathology; D003233:Conjunctivitis, Allergic / Q000139:chemically induced / Q000188:drug therapy* / Q000473:pathology; D004311:Double-Blind Method; D004341:Drug Evaluation; D005260:Female; D006634:Histamine H1 Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions / Q000008:administration & dosage / Q000627:therapeutic use; D010793:Phthalazines / Q000008:administration & dosage / Q000627:therapeutic use*; D012449:Safety; D012882:Skin Tests; D013997:Time Factors
chemical_list: D000485:Allergens; D018926:Anti-Allergic Agents; D006634:Histamine H1 Antagonists; D009883:Ophthalmic Solutions; D010793:Phthalazines; C020976:azelastine