Efficacy and safety of mizolastine 10 mg in a placebo-controlled comparison with loratadine in chronic idiopathic urticaria: results of the MILOR study

Background Mizolastine is a novel histamine HI-antagonist registered in Europe for the management of allergic rhinitis and urticaria. Objectives To compare the clinical efficacy and safety of mizolastine with loratadine and placebo in patients with chronic idiopathic urticatia (CIU). Methods A multicentre, double-blind, parallel group study was designed in which 247 patients with CIU were randomised after a 1-week placebo run-in period to 10 mg daily mizolastine (n = 88), 10 mg daily loratadine (n = 79), or placebo (n = 80) for a 4-week treatment period. Results Mizolastine and loratadine both relieved symptoms of CIU. After 2 weeks' treatment, the severity of pruritus (visual analogue score (VAS) assessed by patients) decreased significantly in both the mizolastine and loratadine groups compared with placebo (mizolastine: -36.7 mm, P = 0.0001; loratadine: -29.8, P = 0.0071; placebo: -16.3); this improvement with both active treatments was maintained throughout the treatment period, the difference being significant only for the mizolastine group (P = 0.0090). Both active treatments were also associated with reduced weekly episodes of urticaria compared with placebo. which was significant after 2 weeks' treatment (mizolastine: 7.9 episodes, P = 0.0061; loratadine: 8.3, P = 0.0221; placebo: 13.3). Angioedema was improved to a clinically significant extent with mizolastine, and loratadine compared with placebo in those patients who had this symptom before treatment. Overall tolerability of both treatments was similar to placebo, and there were no clinically relevant effects on cardiac repolarisation with either mizolastine or loratadine. Conclusion Mizolastine (10 mg daily) is confirmed as an effective and well tolerated agent, comparable to loratadine and superior to placebo, for the management of CIU. Mizolastine acted as rapidly as loratadine in improving urticarial symptoms from the first day of treatment. (C) 1999 Elsevier Science B.V. All rights reserved.