DOSE-RANGING, PLACEBO-CONTROLLED STUDY OF CETIRIZINE NASAL SPRAY IN ADULTS WITH PERENNIAL ALLERGIC RHINITIS

A total of 360 patients with perennial allergic rhinitis were randomiz ed in a placebo-controlled, dose-finding study comparing three concent rations (0.06%, 0.125%, and 0.25%) of a cetirizine nasal spray, admini stered three times a day for 2 weeks. The primary criterion of efficac y was the percentage of days with no or only mild symptoms of rhinitis (PDMaxl), as evaluated by the patients. The median PDMaxl were 16.7%, 30.8%, 42.9%, and 26.7% for the placebo, 0.06%, 0.125%, and 0.25% gro ups, respectively. Although the global comparison among the four group s only approached statistical significance (P = 0.076), the difference (26.2%) between the placebo and 0.125% groups was clinically and stat istically significant (P = 0.011). For the global evaluation by the in vestigator, the best results were seen in the 0.125% group (P = 0.03). The occurrence of adverse events did not differ among the four treatm ent groups and consisted mainly of nasal events, occurring in 22.5%, 1 7.1%, 12.9%, and 24.3% of the patients for the placebo, 0.06%, 0.125%, and 0.25% groups, respectively (P = 0.184). These results indicate th at the 0.125% concentration is significantly better than placebo and o ffers the best therapeutic ratio.