Efficacy of Clonidine Adhesive Patch for Patients With Tourette Syndrome: A Randomized, Double-blind, Placebo-Controlled, Multicenter Clinical Trial

Objective: This study aimed to explore the efficacy of the clonidine adhesive patch for participants with Tourette syndrome (TS). Methods: This randomized, double-blind, placebo-controlled, multicenter phase IV clinical trial included participants with TS at 20 centers between May 2012 and March 2015. Treatment efficacy at week 8 was the primary outcome. The Clinical Global Impression-Severity scale and Improvement scale were the secondary endpoints. Results: This trial included 488 participants, with 121 participants in the 2.0-mg/wk group, 119 participants in the 1.5-mg/wk group, 126 participants in the 1.0-mg/wk group, and 122 participants in the placebo group. For Yale Global Tic Severity Scale score reduction rate, compared with the placebo group (39.60 +/- 25.56), those of the 2.0-mg/wk group (63.21 +/- 32.60) and the 1.5-mg/wk group (68.16 +/- 25.88) were statistically significantly different (all P < 0.001). For total Yale Global Tic Severity Scale score, compared with the placebo group (17.0 +/- 8.03), the score for the 2.0-mg/wk group was 9.9 +/- 8.36 (P < 0.001); 1.5-mg/wk group, 9.6 +/- 8.03 (P < 0.001); and 1.0-mg/wk group, 10.5 +/- 9.28 (P < 0.001). The Clinical Global Impression-Severity scale and Improvement scale scores were statistically significantly different in the 3 clonidine (or experimental) groups compared with the placebo group (all P < 0.001). Conclusions: Larger doses of the clonidine adhesive patch such as 1.5 and 2.0 mg/wk are effective in improving the symptoms and overall function of participants with TS.