Amisulpride versus placebo in the medium-term treatment of the negative symptoms of schizophrenia

Abstract

Background: Amisulpride is a substituted benzamide with high selectivity for dopamine D₂ and D₃ receptors. The purpose of the study was to evaluate the effect of 100 mg amisulpride in patients with predominantly negative symptoms of schizophrenia.Method: This was a multi-centre, randomised, parallel-group, double-blind study. Patients received either amisulpride (100 mg/day) or placebo over a six-month treatment period.Results: A total of 141 patients were included, 69 received amisulpride, 72 placebo. Fifty-eight patients (41%) had received neuroleptic treatment prior to inclusion. The percentage of amisulpride patients completing the study (55%) was significantly higher than that with placebo (32%), and drop-out rates due to lack of efficacy were 27% with amisulpride and 47% with placebo. All efficacy assessments were statistically in favour of amisulpride compared with placebo. The overall incidence of extrapyramidal symptoms was comparable in both groups; only five patients started anti-Parkinsonian treatment during the study (one in the placebo and four in the amisulpride group).Conclusion: Amisulpride is effective in the medium-term treatment schizophrenic patients with predominantly negative symptoms.