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