Efficacy and safety of rupatadine in Japanese adult and adolescent patients with chronic spontaneous urticaria: A double-blind, randomized, multicenter, placebo-controlled clinical trial.

Background: Rupatadine, a novel nonsedating second-generation H1-antihistamine with antiplatelet-activating factor activity, has been used in the treatment of allergic rhinitis and urticaria in European countries since 2003. However, its efficacy and safety in Japanese patients with chronic spontaneous urticaria (CSU) are unknown.

Methods: We conducted a prospective, multicenter, randomized, placebo-controlled, double-blind study in adolescent and adult CSU outpatients aged 12 to < 65 years (JAPIC-CTI No. 152786). Overall, 94, 91, and 92 eligible patients orally received placebo, rupatadine 10 mg, and 20 mg once daily for 2 weeks, respectively. The primary endpoint was change from baseline to the second week of treatment in total pruritus score (TPS, sum of daytime and nighttime pruritus scores).

Results: The results yielded a least squares mean TPS difference of -1.956 between rupatadine 10 mg versus placebo, and -2.121 between rupatadine 20 mg versus placebo (analysis of covariance, both P < 0.001). The incidence of adverse events was 8.5% for placebo, 20.9% for rupatadine 10 mg, and 17.4% for rupatadine 20 mg. Somnolence was the only adverse drug reaction to rupatadine reported in 2 or more subjects. No serious or clinically significant adverse events were observed.

Conclusions: The primary and secondary efficacy endpoints consistently favored rupatadine 10 and 20 mg doses over the placebo. No noteworthy dose-related increase in the incidence of adverse drug reactions was observed. Rupatadine is safe and effective at a dose of 10 mg once daily, and can be safely increased to 20 mg once daily, as necessary.