A MULTICENTER, DOUBLE-BLIND, RANDOMIZED, PLACEBO-CONTROLLED TRIAL COMPARING THE EFFICACY AND TOLERABILITY OF LEVOCABASTINE-OXYMETAZOLINE NASAL SPRAY WITH LEVOCABASTINE AND OXYMETAZOLINE ALONE IN THE SYMPTOMATIC TREATMENT OF SEASONAL ALLERGIC RHINITIS

A total of 1015 patients participated in three 1-week, multicenter, do uble-bind, randomized placebo-controlled trials undertaken to assess t he therapeutic efficacy and tolerability of twice daily administration of a nasal spray containing a combination of levocabastine (0.5 mg/mL ) and oxymetazoline (0.5 mg/mL) (levocabastine-D) versus that of eithe r agent alone in the treatment of ragweed-induced seasonal allergic rh initis. As these studies shared a common protocol, the data have been pooled. Patient assessments revealed that the mean change in area unde r the curve (AUC) from baseline over the entire treatment period was s ignificantly greater in patients treated with levocabastine or levocab astine-D than in those receiving placebo for all symptoms evaluated (n asal congestion; P less than or equal to 0.05 and sneezing, rhinorrhea , nasal itching, ocular symptoms, total key symptoms, total all sympto ms; P less than or equal to 0.001). Corresponding changes in patients treated with oxymetazoline alone did not attain statistical significan ce. Day-by-day analysis demonstrated that the beneficial effects seen with levocabastine and levocabastine-D were maintained throughout the treatment period for all symptoms except nasal congestion (Days 1 and 2 only); oxymetazoline provided significant relief from nasal congesti on only and only on the first day of treatment. Investigator assessmen ts revealed similar trends. Global evaluations of therapeutic efficacy revealed that 44% of levocabastine-treated patients and 52% of patien ts treated with levocabastine-D considered therapeutic efficacy to be excellent or good compared with 39% of those on oxymetazoline and 26% on placebo (P less than or equal to 0.01 versus placebo). Adverse expe riences were reported by 30% of levocabastine-treated patients, 40% of patients treated with levocabastine-D and oxymetazoline, and 32% of p lacebo controls, with no statistically significant intergroup differen ces in incidence or type. In conclusion, twice daily levocabastine nas al spray is effective and well-tolerated for the treatment of ragweed- induced seasonal allergic rhinitis with an adverse effect profile comp arable with that of placebo. Addition of oxymetazoline to the topical antihistamine does not appear to provide significant additional clinic al benefit compared to that observed with levocabastine alone, and tac hyphylaxis to the decongestant effect of the topical vasoconstrictor o ccurs within clays of treatment initiation.