Efficacy and safety of pramipexole in idiopathic restless legs syndrome: a polysomnographic dose-finding study--the PRELUDE study

Sleep Med. 2006 Aug;7(5):407-17. doi: 10.1016/j.sleep.2006.03.011. Epub 2006 Jul 3.


Background and purpose: To evaluate the effects of pramipexole (0.125-0.75 mg/d) on polysomnographic (PSG) measures and patient and clinician ratings of restless legs syndrome (RLS).

Patients and methods: Patients (n=109) with moderate to severe RLS were randomized to placebo or fixed doses of pramipexole during a 3-week, double-blind, placebo-controlled, dose-finding study.

Results: In each pramipexole dose group, the periodic limb movements during time in bed index (PLMI) decreased significantly, compared with placebo (adjusted mean difference in log-transformed data: 0.125 mg, -1.54; 0.25 mg, -1.93; 0.50 mg, -1.89; and 0.75 mg, -1.52; P<0.0001). At all doses, International RLS Study Group Rating Scale (IRLS) scores were also significantly reduced, with the greatest adjusted mean reduction in the 0.50mg group (-17.01). At all but the lowest pramipexole dose, the percentage of responders (> or =50% reduction of IRLS score) was substantially higher than for placebo (61.9-77.3, vs 33.3%). In the pramipexole groups, 50.0-77.3% of patients rated their condition as 'much better' or 'very much better', compared with 38.1% of patients in the placebo group (P=0.0139 for the 0.50 mg dose). Clinical global impressions (CGI) scale ratings of 'much improved' or 'very much improved' were given to 61.9-86.4% of patients in the pramipexole groups, compared with 42.9% in the placebo group (P<0.05 for the 0.25, 0.50, and 0.75 mg groups). Pramipexole was well tolerated and did not produce somnolence at any dose.

Conclusion: Pramipexole is effective and safe in the treatment of both objective and subjective facets of RLS.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Benzothiazoles / administration & dosage
  • Benzothiazoles / adverse effects
  • Benzothiazoles / therapeutic use*
  • Dopamine Agonists / administration & dosage
  • Dopamine Agonists / adverse effects
  • Dopamine Agonists / therapeutic use*
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Middle Aged
  • Polysomnography
  • Pramipexole
  • Quality of Life
  • Restless Legs Syndrome / drug therapy*
  • Sleep / drug effects*


  • Benzothiazoles
  • Dopamine Agonists
  • Pramipexole