Background: Long-term efficacy and tolerability data are not yet available for patch formulations of dopamine agonists in restless legs syndrome.
Methods: Efficacy and safety of rotigotine (0.5-4mg/24h), formulated as a once-daily transdermal system (patch), were investigated in an open extension (SP710) of a preceding 6-week placebo-controlled trial (SP709, 341 randomized patients) in patients with idiopathic restless legs syndrome. For efficacy assessment the international RLS severity scale (IRLS), the RLS-6 scales, the clinical global impressions (CGI) and the QoL-RLS questionnaire were administered. In addition, long-term tolerability and safety were assessed.
Results: Of 310 patients who finished the controlled trial, 295 (mean age 58+/-10 years, 66% females) with a mean IRLS score of 27.8+/-5.9 at baseline of SP709 were included. We report results after one year of this ongoing long-term trial. Two hundred twenty patients (retention rate=74.6%) completed the 12-month follow-up period. The mean daily dose was 2.8+/-1.2mg/24h with 4mg/24h (40.6%) being the most frequently applied dose; 14.8% were sufficiently treated with 0.5 or 1.0mg/24h. The IRLS total score improved by ?17.4+/-9.9 points between baseline and end of Year 1 (p<0.001). The other measures of severity, sleep satisfaction and quality of life supported the efficacy of rotigotine (p<0.001 for pre-post-comparisons of all efficacy variables). The tolerability was described as "good" or "very good" by 80.3% of all patients. The most common adverse events were application site reactions (40.0%), which led to withdrawal in 13.2%. Further relatively frequent adverse events were nausea (9.5%) and fatigue (6.4%). Two drug-related serious adverse events, nausea and syncope, required hospitalization. Symptoms of augmentation were not reported by the patients.
Conclusion: Rotigotine provided a stable, clinically relevant improvement in all efficacy measures throughout one year of maintenance therapy. The transdermal patch was safe and generally well tolerated by the majority of patients. Comparable to any transdermal therapy, application site reactions were the main treatment complication.