Zimeldine tolerability in comparison to amitriptyline and placebo: findings from a multicentre trial

Zimeldine tolerability was compared to amitriptyline and placebo in a large multicentre study performed at three clinical research units in the U.S.A. Prior to a placebo washout period of 3-7 days, patients were randomly assigned to zimeldine, a potent and selective 5-HT reuptake blocker, amitriptyline or placebo. Dosage range was 75-300 mg/day for active medications, and the scheduled treatment period was 4 weeks. The side-effects were recorded by using a Treatment Emergent Symptom Scale (TESS). Vital signs were monitored and laboratory investigations, including chemistry and drug plasma levels, were performed. Two hundred and sixty-three patients were included in the safety evaluation. Side-effects, particularly anticholinergic effects but also drowsiness and cardiovascular effects, were much less pronounced in the zimeldine group compared to the amitriptyline group. Only marginal differences in side-effects were reported between zimeldine and placebo. Significantly more patients receiving amitriptyline were withdrawn from treatment as a result of adverse effects. Thus, zimeldine appears to be an effective antidepressant with marked advantages with regard to tolerability. It is therefore an important new contribution to the treatment of depressive disorders.