Efficacy and safety of amisulpride 50 mg versus paroxetine 20 mg in major depression: a randomized, double-blind, parallel group study.

The efficacy of amisulpride in depressive disorders has been demonstrated in dysthymia and in double depression. Limited data are available in major depression. A randomized, double-blind, parallel group, multicentre study was set up to compare the efficacy and tolerability of amisulpride (50 mg o.d.) and paroxetine (20 mg o.d.) for 8 weeks in 272 patients with major depression (DSM-IV and baseline Hamilton Depression Rating Scale (HAMD) score > or = 18). The study was designed as a non-inferiority trial based on the proportion of responders (> or = 50% decrease in HAMD total score) at end-point, with a maximal allowable difference of 15%; secondary end-points included HAMD total and cluster scores, Montgomery and Asberg Depression Rating Scale score and responders rates and Clinical Global Impression improvement. The tolerability evaluation was based on incidence of adverse events and routine laboratory tests. The results did not disclose statistically significant differences between treatments, although the hypothesis of an efficacy difference between the two treatments within the set limit at day 56 could not be accepted. The issue of non-inferiority trials is discussed.