Efficacy and tolerability of sumanirole in restless legs syndrome: a phase II, randomized, double-blind, placebo-controlled, dose-response study.
OBJECTIVE
To compare the efficacy, safety and tolerability of sumanirole with placebo in patients with idiopathic restless legs syndrome (RLS).


METHODS
In this double-blind, placebo-controlled, randomized, parallel-group, dose-response study, 270 patients with idiopathic RLS were enrolled and randomized to receive sumanirole 0.5, 1.0, 2.0, or 4.0mg, or placebo. The primary efficacy endpoint was mean change of the total score of the International Restless Legs Scale (IRLS-10), a 10-item scale, from baseline to end of maintenance. Secondary assessments included polysomnography (PSG) variables.


RESULTS
Treatment with sumanirole was well tolerated. Mean change in IRLS-10 showed no statistically significant change compared with placebo at any dose, although the mean change with the 4.0-mg dose was numerically greater than the other doses and placebo. PSG variables, specifically the periodic leg movements during sleep, showed statistically significant dose-related improvement in favor of sumanirole. Consistent with earlier multinational, multicenter studies in RLS, high placebo response rates were seen with IRLS-10 but not with PSG variables.


CONCLUSIONS
Given data published in Parkinson's disease, the dose range of sumanirole selected here may have been too low. Alternatively, dopamine D(2) selective agents could be intrinsically less effective than agonists with combined D(2)/D(3) activity. Sumanirole demonstrated an excellent safety profile.
Garcia-Borreguero
Diego
D
Department of Neurology, Fundación Jiménez Díaz, Sleep Disorders Unit, Universidad Autónoma de Madrid, Madrid, Spain. dgb@iis.es
Winkelman
John
J
Adams
Alieu
A
Ellis
Amanda
A
Morris
Mark
M
Lamb
Janice
J
Layton
Gary
G
Versavel
Mark
M
D000328:Adult; D000368:Aged; D001562:Benzimidazoles / Q000008:administration & dosage* / Q000009:adverse effects; D018491:Dopamine Agonists / Q000008:administration & dosage* / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000187:drug effects; D012148:Restless Legs Syndrome / Q000188:drug therapy*; D016896:Treatment Outcome
D001562:Benzimidazoles; D018491:Dopamine Agonists; C108539:U 95666E