Abstract: Three double-blind, parallel group, randomised, controlled trials have been conducted on 263 patients. The two phase II studies were relatively small, were conducted over the short term (12 weeks), and used relatively low doses of ropinirole (mean administered doses 3.3 and 3.5 mg/d) in a twice daily regime. In view of this clinical heterogeneity and some statistical heterogeneity, the results of these trials have not been included in a meta-analysis. The conclusions of this review are based on the evidence from a single phase III study which was medium term (26 weeks) and used ropinirole doses in line with the current UK licensed maximum in a thrice daily regime. In view of difficulties in assessing changes in off time in Leiberman 98, caused by the initial imbalance between the arms of the trial, it is unsafe to draw any firm conclusion about the effect of ropinirole on off time. However, as an adverse event, dyskinesia was significantly increased in those who received ropinirole (Leiberman 98; odds ratio 2.90; 1.36, 6.19 95% CI; Table 8). Measurements of motor impairments and disability were poor in this study with incomplete information available. Levodopa dose could be reduced in Leiberman 98 with a significantly larger reduction on ropinirole than on placebo (weighted mean difference 180 mg/d; 106, 253 95% CI; Table 2). No significant differences in the frequency of adverse event reports were noted between ropinirole and placebo apart from the increase in dyskinesia with ropinirole. There was a trend towards fewer withdrawals from ropinirole in Leiberman 98 but this did not reach statistical significance. Ropinirole therapy can reduce levodopa dose but at the expense of increased dyskinetic adverse events. No clear effect on off time reduction was found but this may have been due to the under-powering of the single evaluable trial. Inadequate data on motor impairments and disability was collected to assess these outcomes. These conclusions apply to short and medium term treatment, up to 26 weeks. Further longer term trials are required, with measurements of effectiveness, and also studies to compare the newer with the older dopamine agonists.

Plain-language summary: Three trials have compared ropinirole with an inactive placebo in 263 patients in the later stages of Parkinson's disease. Two studies were relatively small, were conducted over the short term (12 weeks), and used relatively low doses of ropinirole (maximum allowed 8 and 10 mg/d) in a twice daily administration regime. For these reasons, the results of these trials have not been included in a statistical overview. The other study was medium term (26 weeks) and used ropinirole doses in line with the current UK licensed maximum (24 mg/d) in a three times a day regime. The conclusions of this review are based on this single trial and thus should be viewed with some caution. No clear difference in the time patients spent in the immobile off state was found between ropinirole and placebo. However, this was probably due to there being too few patients in the trial. Measurements of physical difficulties and problems with activities of daily living (such as bathing, shopping, etc.) were poor in these studies with incomplete information available. Levodopa dose reduction was greater with ropinirole than placebo by 180 mg/d. However, dyskinesia was increased in those who received ropinirole (2.9 times more common with ropinirole than placebo). No other differences in side effects or withdrawals from treatment were found. Ropinirole reduces levodopa dose but at the expense of increased dyskinetic side effects. No clear effect on off time reduction was found in this single trial. Side effects were similar with ropinirole and placebo. These conclusions apply to short and medium term treatment, up to 26 weeks. Further longer term trials are required, with measurements of quality of life and costs, and also studies to compare the newer with the older dopamine agonists.