[Action of piribedil in Parkinson disease. Multicenter study]

Several controlled trials have shown that Trivastal (piribedil), a direct dopamine agonist, is active in the treatment of Parkinson's disease. The aim of the present clinical trial was to assess the efficacy of Trivastal 50 mg LP administered as monotherapy in patients naive to treatment with L-dopa.

This 3-month multicenter study was conducted in 113 patients (66 men and 47 women), aged 63.1 +/- 0.6 years, with a 2.1 +/- 0.2 year history of Parkinson's disease and a mean Hoehn and Yahr stage of 1.82. Tremor was the predominant clinical feature in 42 patients; the 71 others presented with the full parkinsonian syndrome. Trivastal 50 mg LP doses were increased stepwise, up to doses of 150-250 mg/day at the end of the 3-month study period. Patients were clinically assessed at 1, 2 and 3 months using the Webster scale and the HARD depression scale.

In the 90 patients who completed the study, tremor fell from 1.7 to 1.0 (-41%, p < 0.001), bradykinesia from 1.5 to 0.8 (-47%, p < 0.001) and rigidity from 1.3 to 0.9 (-31%, p < 0.001). The 32 patients in whom tremor was the predominant feature improved their total score on the Webster scale from 5.8 to 4.7 (-19%, p < 0.05). The 58 patients with the full parkinsonian syndrome improved their total Webster score from 11.8 to 6.9 (-42%, p < 0.001). The depression score fell from 10.2 to 7.3 (p < 0.001), the most marked improvement being in mood and inhibition.

Monotherapy with Trivastal 50 mg LP at a mean dose of 200 mg/day is effective on the major symptoms of Parkinson's disease.