Pergolide compared with bromocriptine in Parkinson's disease: a multicenter, crossover, controlled study. Pergolide in the treatment of Parkinson's disease.
We compared the efficacy and safety of pergolide and bromocriptine in 57 patients with Parkinson's disease (PD) with a declining response to levodopa therapy in a single-blind, crossover study. Patients were placed randomly on the sequence bromocriptine-pergolide (12 + 12 weeks) or vice versa. Regular evaluations using the New York University Parkinson's Disease Scale were performed by a clinician blinded to treatment assignment. Patients' and clinicians' impressions also were recorded. The average daily dose of pergolide was 2.3 +/0- 0.8 mg, and that of bromocriptine was 24.2 +/- 8.4 mg. Significantly greater efficacy was demonstrated by both drugs as adjunctive therapy to levodopa compared with previous treatment of levodopa alone (pergolide, p = 0.0001; bromocriptine, p = 0.0005; Wilcoxon t test). Pergolide was more effective than bromocriptine in daily living scores (p = 0.020) and motor scores (p = 0.038). No difference in dyskinesias, dystonias, and psychosis was observed. Adverse events were more frequent in bromocriptine-treated patients. Most patients and physicians preferred pergolide to bromocriptine. Pergolide as adjunctive therapy to levodopa was more effective than bromocriptine in this short-term trial. Three trials evaluated the efficacy and safety of pergolide. Eighty-six de novo patients and 314 patients already receiving levodopa were enrolled in an open-label study. Of the de novo patients, 47.5% showed a marked or moderate improvement and 32% showed a mild improvement. In the levodopa add-on group, 53.8% showed marked or moderate improvement and 36.3% showed mild improvement. In a short-term, double-blind study, the efficacy of pergolide was compared with that of bromocriptine. One hundred seventy-two patients were randomized to receive pergolide, and 173 were randomized to receive bromocriptine. In de novo patients, bromocriptine (n = 49) and pergolide (n = 49) demonstrated similar efficacy. However, significantly more levodopa-treated patients in the pergolide group, compared with the bromocriptine group, demonstrated marked or moderate improvements in several items of the rating scale score. In a long-term study, 151 of 314 patients receiving pergolide in combination with levodopa remained in the study for 3 years, and 127 for 4 years, and in these patients the initial improvement was maintained. In 18 of 62 de novo patients, the initial improvement was maintained for up to 3 years. These trials indicate that pergolide has efficacy in patients with Parkinson's disease, either as monotherapy or in combination with levodopa.
Although pergolide is superior to bromocriptine in reducing motor impairments and disability, no firm conclusions regarding levodopa-induced motor complications can be reached. Levodopa dose reduction, adverse events and withdrawals from treatment are similar for the two agonists. The small advantage of pergolide in efficacy does not take into account its additional cost compared with bromocriptine.