title: Slower progression of Parkinson's disease with ropinirole versus levodopa: The REAL-PET study.
abstract: Preclinical studies suggest ropinirole (a D2/D3 dopamine agonist) may be neuroprotective in Parkinson's disease (PD), and a pilot clinical study using (18)F-dopa positron emission tomography (PET) suggested a slower loss of striatal dopamine storage with ropinirole compared with levodopa. This prospective, 2-year, randomized, double-blind, multinational study compared the rates of loss of dopamine-terminal function in de novo patients with clinical and (18)F-dopa PET evidence of early PD, randomized 1 to 1 to receive either ropinirole or levodopa. The primary outcome measure was reduction in putamen (18)F-dopa uptake (Ki) between baseline and 2-year PET. Of 186, 162 randomized patients were eligible for analysis. A blinded, central, region-of-interest analysis showed a significantly lower reduction (p = 0.022) in putamen Ki over 2 years with ropinirole (-13.4%; n = 68) compared with levodopa (-20.3%; n = 59; 95% confidence interval [CI], 0.65-13.06). Statistical parametric mapping localized lesser reductions in (18)F-dopa uptake in the putamen and substantia nigra with ropinirole. The greatest Ki decrease in each group was in the putamen (ropinirole, -14.1%; levodopa, -22.9%; 95% CI, 4.24-13.3), but the decrease was significantly lower with ropinirole compared with levodopa (p < 0.001). Ropinirole is associated with slower progression of PD than levodopa as assessed by (18)F-dopa PET.
authors.affiliation: Faculty of Medicine, Imperial College, Hammersmith Hospital, London, United Kingdom.
authors.forename: Alan L
authors.initials: AL
authors.lastname: Whone
authors.forename: Ray L
authors.initials: RL
authors.lastname: Watts
authors.forename: A Jon
authors.initials: AJ
authors.lastname: Stoessl
authors.forename: Margaret
authors.initials: M
authors.lastname: Davis
authors.forename: Sven
authors.initials: S
authors.lastname: Reske
authors.forename: Claude
authors.initials: C
authors.lastname: Nahmias
authors.forename: Anthony E
authors.initials: AE
authors.lastname: Lang
authors.forename: Olivier
authors.initials: O
authors.lastname: Rascol
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Ribeiro
authors.forename: Philippe
authors.initials: P
authors.lastname: Remy
authors.forename: Werner H
authors.initials: WH
authors.lastname: Poewe
authors.forename: Robert A
authors.initials: RA
authors.lastname: Hauser
authors.forename: David J
authors.initials: DJ
authors.lastname: Brooks
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002421:Caudate Nucleus / Q000000981:diagnostic imaging / Q000378:metabolism; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism; D018450:Disease Progression; D004298:Dopamine / Q000378:metabolism*; D018491:Dopamine Agonists / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D005462:Fluorine Radioisotopes / Q000493:pharmacokinetics; D006801:Humans; D007211:Indoles / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D007980:Levodopa / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D011446:Prospective Studies; D011699:Putamen / Q000000981:diagnostic imaging / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000187:drug effects*; D012720:Severity of Illness Index; D013378:Substantia Nigra / Q000000981:diagnostic imaging / Q000378:metabolism; D014055:Tomography, Emission-Computed
chemical_list: D018491:Dopamine Agonists; D005462:Fluorine Radioisotopes; D007211:Indoles; D017448:Receptors, Dopamine D2; C046649:ropinirole; D007980:Levodopa; D004298:Dopamine