Background: Levocetirizine, a second-generation antihistamine for symptomatic treatment of allergic rhinitis and chronic idiopathic urticaria, has not been previously studied in US patients.
Objective: To assess the efficacy and safety of levocetirizine in improving symptoms and health-related quality of life in US adults with seasonal allergic rhinitis (SAR).
Methods: This multicenter, double-blind trial randomized adults with SAR, sensitized to at least 1 grass allergen, to receive levocetirizine, 5 mg, or placebo once daily in the evening for 2 weeks. The primary end point was the 24-hour reflective Total 5-Symptom Score (T5SS; sum of rhinorrhea, sneezing, nasal congestion, and nasal and ocular pruritus) during the entire treatment period. Secondary assessments included the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), Work Productivity and Activity Impairment-Allergy Specific (WPAI-AS) questionnaire, and Epworth Sleepiness Scale (ESS), each assessed at week 1, week 2, and the end of treatment.
Results: The intent-to-treat population comprised 287 patients taking levocetirizine and 290 taking placebo, with no significant between-group differences at baseline. Levocetirizine resulted in significantly greater improvement from baseline vs placebo in the T5SS (P < .001), overall RQLQ score (P < .001), general and work-related WPAI-AS subscores (P < .05), and ESS score (P < .001). Overall incidence of treatment-emergent adverse events was 14.4% for levocetirizine and 18.4% for placebo. The incidence of somnolence and fatigue was 0.7% and 1.8% with levocetirizine and 1.0% and 0% with placebo, respectively.
Conclusions: Levocetirizine was well tolerated and was significantly more effective than placebo in improving the naso-ocular symptoms and health-related quality of life in US patients with SAR.
Trial registration: ClinicalTrials.gov NCT00621959.