Objective: To assess the efficacy, safety, and tolerability of the dopamine agonist ropinirole in the treatment of patients with moderate to severe primary restless legs syndrome (RLS).
Patients and methods: This multicenter, 12-week, double-blind, placebo-controlled, flexible-dose study enrolled US patients and was conducted between September 2003 and May 2004. Patients were randomized to ropinirole or placebo, 0.25-4.0 mg as needed and tolerated, once daily, 1 to 3 hours before bedtime. The primary end point was mean change from baseline to week 12 in International Restless Legs Scale (IRLS) total score. Key secondary efficacy measures included the Clinical Global Impression-Improvement scale.
Results: A total of 381 patients were enrolled; 164 (87.7%) of 187 patients randomized to ropinirole and 167 (86.1%) of 194 randomized to placebo completed the study. Significant treatment differences favoring ropinirole, compared with placebo, were observed for change in IRLS total score at week 12 (adjusted mean treatment difference, -3.7; 95% confidence interval, -5.4 to -2.0; P < .001) and for all 3 key secondary end points: mean change from baseline in IRLS total score at week 1 and proportion of patients who were much/very much improved on the Clinical Global Impression Improvement scale at weeks 1 and 12. Ropinirole was associated with significantly greater Improvements in subjective measures of sleep disturbance, quantity, and adequacy; quality of life; and anxiety. Although treatment differences favoring ropinirole in daytime somnolence were observed, they were not statistically significant (P = .10). Ropinirole was generally well tolerated, with an adverse-event profile consistent with other dopamine agonists.
Conclusion: This study confirms that ropinirole improves RLS symptoms and subjective measures of sleep, quality of life, and anxiety and that it is generally well tolerated.