Early piribedil monotherapy of Parkinson's disease: A planned seven-month report of the REGAIN study.

Abstract

Piribedil is a D2 dopamine agonist, which has been shown to improve symptoms of Parkinson's disease (PD) when combined with L-dopa. The objective of this study was to compare the efficacy of piribedil monotherapy to placebo in patients with early PD over a 7-month period. Four hundred and five early PD patients were randomized (double-blind) to piribedil (150-300 mg/day) or placebo. L-dopa open-label supplementation was permitted. Unified Parkinson Disease Rating Scale part III (UPDRS III) score as the last observation on monotherapy over 7 months was the primary outcome measure. Secondary outcomes were proportion of responders (UPDRS III improvement > 30%), patients remaining on monotherapy after 7 months, UPDRS III subscores, and UPDRS II. UPDRS III improved on piribedil (-4.9 points) versus a worsening on placebo (2.6 points; estimated effect = 7.26 points; 95% CI = 5.38-9.14; P < 0.0001). The proportion of responders was significantly higher for piribedil (42%) than for placebo (14%) (OR = 4.69; 95% CI = 2.82-7.80; P < 0.001). Piribedil significantly improved several UPDRS III subscores. UPDRS II improved on piribedil by -1.2 points, while it deteriorated by 1.5 points on placebo (estimated effect = 2.71; 95% CI = 1.8-3.62; P < 0.0001). The proportion of patients remaining on monotherapy after 7 months was greater in the piribedil group (OR = 3.72; 95% CI = 2.26-6.11; P < 0.001). Safety was consistent with that reported for other dopamine agonists, gastrointestinal side effects being the most common (22% of patients in piribedil group vs. 14% on placebo). Piribedil is effective and safe as early PD therapy.

• Authors: Olivier Rascol, Bruno Dubois, Alexandre Castro Caldas, Stephen Senn, Susanna Del Signore, Andrew Lees, Parkinson REGAIN Study Group
• Journal: Movement disorders : official journal of the Movement Disorder Society (Mov Disord) Vol. 21 Issue 12 Pg. 2110-5 (Dec 2006) ISSN: 0885-3185 [Print] United States
• PMID: 17013922 (Publication Type: Clinical Trial, Comparative Study, Journal Article, Multicenter Study, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: Copyright 2006 Movement Disorder Society.

Chemical References

• Antiparkinson Agents
• Levodopa
• Piribedil

Topics

• Adult
• Aged
• Antiparkinson Agents (therapeutic use)
• Dose-Response Relationship, Drug
• Double-Blind Method
• Female
• Follow-Up Studies
• Humans
• Levodopa (therapeutic use)
• Male
• Middle Aged
• Outcome Assessment, Health Care
• Parkinson Disease (drug therapy)
• Piribedil (therapeutic use)
• Severity of Illness Index
• Single-Blind Method
• Time Factors